A device for removably securing a reactor vessel washer to a reactor vessel stud for use in combination with a reactor vessel including a dome having a first flange positioned abutting a second flange of a reactor body, a plurality of reactor studs are disposed in both the first and second flanges and a nut and washer arrangement secured to the stud for rigidly attaching the dome to the body. The device comprises a retainer removably disposed on the stud and operable to mate the washer to the stud to maintain the positional relationship of the stud and washer as the stud is removed from the dome and the body.

1. Field of the Invention
The present invention relates generally to nuclear reactor vessels and, more particularly, to a device for securing a reactor vessel washer to a reactor vessel stud, allowing the stud and washer to be maintained as a mated pair during removal and replacement of the stud.
2. Description of the Prior Art
In a commercial nuclear reactor vessel, heat, from which steam and ultimately electricity are generated, is produced by fission of a fissile material, such as uranium disposed inside the reactor vessel. The reactor vessel includes a body having a cylindrical wall with two ends. The wall includes an outwardly extending flange at one end, and a semicircular domed bottom is integrally attached to the opposite end of the wall. A reactor dome is attached to the body and is positioned atop the body. The dome has a semicircular shape with an annular shaped lip portion as is well known in the art. An outwardly extending flange is disposed around the circumference of the dome at the lip portion. The body flange is positioned abutting the dome flange. A plurality of holes through the dome flange are in registry with a plurality of holes inserted partially through the body flange. Each hole in the dome mates with a corresponding hole in the body flange forming a matched pair of holes. A plurality of washers, in registry with a flange hole, are positioned over the matched holes. A plurality of studs each having two ends and a threaded shaft are used to attach the dome to the body. The plurality of studs, each with a nut attached at one end, are disposed respectively through the matched holes with the stud and washer forming a mated pair. The studs are threaded into both flanges such that one end passes through both flanges, and the other end, which accepts the nut, extends upwardly from the abutting flanges. The stud is disposed in a matched pair of holes such that the nut abuts the top of the washer. The nut and washer together function to rigidly attach the dome to the body.
Due to maintenance procedures, regulations, and the need to replenish expended fuel, the interior of the reactor vessel should be periodically inspected. To inspect the interior, the dome may be repeatedly removed. However, once the dome is initially installed, during reinstallation of the dome the stud and washer should be maintained as a mated pair. This is because the stud is stressed when it is installed, and the nut and washer, thereafter, conform to the stressed stud. Therefore, each stud, nut and washer is slightly altered and installing them on a different stud could cause them to fit improperly.
One means of removing the reactor vessel head to facilitate inspection of the interior of the vessel is disclosed in U.S. Pat. No. 4,873,760. This patent discloses an apparatus which includes a gripper and is positioned over the dome. The gripper unthreads a nut associated with a particular stud, and then an attracting device magnetically attracts the washer such that the washer is forced into the gripper and abuts the nut. The gripper places the nut and washer on a pin and repeats the process for each of the nuts to be removed. The studs are then unthreaded, and the dome is removed.
Another known method includes an apparatus, generally referred to in the art as an Automated Stud Handling and Transportation System, which is positioned on the vessel head flange. A stud remover of this apparatus completely removes the stud with the nut secured on one end of the stud. The washer is manually removed from the stud and affixed to a hook on the apparatus. Next, a movable arm for holding the stud attaches to the stud. The stud remover then moves so that it is positioned over an adjacent stud. The above process is repeated until all studs are removed. Once all the studs are removed, the dome is removed by a crane. To install the studs, the process is reversed.
A major drawback to each of the above methods is that the stud and washer are removed separately. Thus, repeatedly removing and installing the studs makes the identification of which washer should be associated with a particular stud extremely difficult. As stated above, the same nut and washer should be maintained as a mated pair each time the stud is removed and then replaced. Prudent practice dictates that if a particular stud and its associated washer and nut can't be identified, a new nut and washer should be installed. This obviously results in increased costs each time the vessel head is removed and thereafter re-installed.
Another drawback to each of the above methods is that when installing the studs a worker must carefully position each washer concentrically over the matched holes. This is a time consuming operation, and, therefore, a worker will have increased exposure to radiation in the reactor. Still further, if the washer is improperly aligned with the matched holes, the washer may be damaged as the stud is inserted.
Consequently, a need exists for a simple device for removably securing a reactor vessel washer to a vessel stud allowing the washer and stud to be maintained as a mated pair during removal and replacement of the stud.

Device for securing a reactor vessel washer to a reactor vessel stud


A rotating electric machine wherein sub slots serving as cooling fluid ducts in the axial direction are provided at the bottoms of the coil slots formed in the rotor, radial cooling fluid ducts are formed through the field coil of the rotor in the radial direction of the rotor and juxtaposed in the axial direction of the rotor, so as to communicate the sub slots with the air gap, and radial cooling fluid ducts are formed through the stator in the radial direction of the stator and juxtaposed in the axial direction of the rotor, corresponding in position to the radial cooling fluid ducts in the rotor, so as to communicate the inner periphery of the stator with the outer periphery of the stator.

The present invention relates to a rotating electric machine such as a turbine generator having its rotor provided with a ventilation mechanism which directly cools the rotor with cooling fluid.
In general, a mechanism is well known wherein ventilation ducts are provided in the stator or the rotor of a rotating electric machine such as a turbine generator, and cooling fluid such as air or hydrogen gas is passes through the ventilation ducts so that the coils and the iron cores heated up due to the generated joule loss and iron loss are cooled down.
From the viewpoint of achieving a high cooling performance, a direct cooling system which cools the coils by putting them in direct contact with cooling fluid is widely employed as a mechanism for cooling the rotor. Recent requirements have been for the compatibility of the scale-up of the rotating electric machines and the reduction in the costs of such high capacity machines. The high capacity requirements tend to increase the length of the rotor in the direction along the rotor shaft of the rotating electric machine.
A typical structure of the conventional ventilation mechanism for use in a rotating electric machine will now be described in reference to FIGS. 16˜19.
FIG. 16 schematically shows in vertical cross section a part of a turbine generator having the rotor provided with a radial flow cooling system. In FIG. 16 are shown a turbine generator 1, a stator 2, a rotor 3 and a rotor shaft 4.
An axial fan 5 installed near one end of the rotor shaft 4 generates the flow of cooling fluid 6 (depicted with arrows) passing through the various ventilation ducts in the rotating electric machine. Sub slots 7 to serve as ventilation ducts for conducting the cooling fluid 6 through the rotor 3 are provided underneath the coil slots of the rotor 3, running along the rotor shaft 4. Rotor field coil (of electric conductor) 8 of laminated structure are fitted in the coil slots formed above the sub slots 7. Radial ducts (holes: radial cooling fluid ducts) 9 for guiding the cooling fluid from the sub slots 7 into the laminated field coils 8 are cut in the laminated field coils 8 in the radial direction of the rotor 3. The radial ducts 9 are juxtaposed at a predetermined interval in the axial direction of the rotor and the discharging holes 10 of the radial ducts 9 are also juxtaposed on the outer circumferential surface of the rotor 3 in the axial direction of the rotor 3.
An air gap 11 is defined between the inner circumferential surface of the stator 2 and the outer circumferential surface of the rotor 3.
The iron core 12 of the stator 2 is provided with stator cooling ducts (cooling fluid ducts) 13 which are juxtaposed in the axial direction of the rotor shaft 4 and serve as radial ventilation ducts (holes) for guiding the cooling fluid 6 through the stator 2. Reference numeral 14 indicates the stator coil of electric conductor fitted in the stator coil slots, and numeral 15 denotes a cooler for cooling down the cooling fluid 6 whose temperature is elevated as a result of cooling the parts of the turbine generator 1.
The constituent elements (before lamination) of the field coils 8 are flat plates (not shown) of electric conductor and each element has ventilation holes arranged in the axial direction. A plurality of such elements are stacked (laminated) one upon another in the radial direction in such a manner that the ventilation holes are registered one upon another to form plural juxtaposed radial ducts 9 arranged in the axial direction of the field coils 8.
These plural radial ducts 9 are communicated with the sub slots 7 provided at the bottom of the field coil 8. When the rotor 3 starts rotating, the cooling fluid 6 flows into the sub slots 7 due to the pumping action caused by the pushing force of axial fan 5 and the centrifugal force created in the radial ducts 9. Part of cooling fluid 6 forced out by the axial fan 5 flows toward the air gap 11 and the far end of the stator coil 14. Part of the cooling fluid 6 entering the sub slots 7 is distributed into the respective radial ducts 9 while flowing from the central position of the rotor shaft 3 toward the far end thereof. Then, the cooling fluid 6 cools the field coils 8 while it is flowing through the radial ducts 9, and the cooling fluid 6 is discharged from the outlet holes 10 of the radial ducts 9 into the air gap 11. Thereafter, the cooling fluid 6 flows from the air gap 11 into stator cooling ducts 13, cools the iron core 12 and the stator coil 14, and joins that part of the cooling fluid 6 which has cooled the end of the stator coil 14. Next, the confluent cooling fluid 6 whose temperature is elevated as a result of having cooled the heat generating parts, flows into the cooler 15 for lowering the temperature of the cooling fluid 6. The thus cooled fluid 6 finally returns to the axial fan 5 to complete the whole circulation.
The rotors of radial flow cooling type are disclosed in, for example, JP-A-09-285025, JP-A-2005-210893 and JP-A-10-178754.
The rotors of radial flow cooling type are advantageous in that both facility in fabrication of the rotor 3 and reduction in production cost can be attained since plural radial ducts 9 can be formed in the field coils 8 simply by stacking (laminating) flat conductors of the same structure in the radial direction. On the other hand, since the cooling of the field coil 8 is performed by distributing the cooling fluid 6 flowing through the sub slots 7 into the respective radial ducts 9 in the order of increasing distance from the axial fan 5, the rate of flow of the cooling fluid 6 decreases with the distance from the axial fan 5 due to the increase in the flow resistance as the distance from the axial fan 5 increases. This situation gives rise to a problem that the temperature of the field coil 8 becomes higher near the central part thereof. Therefore, this problem has made it difficult to increase the axial length of the rotor 3 for higher capacity. Thus, the rotors of radial flow cooling type have been applied to relatively small capacity machines having ratings of up to 100 MVA.
There is another type of rotor, i.e. rotor of gap pick up diagonal flow cooling type, known in, for example, JP-A-2000-139050.
FIG. 17 schematically shows in partial cross section of a turbine generator having a rotor of gap pick up diagonal flow cooling type.
The laminated field coil 8 of the rotor 3 has V-shaped diagonal ducts 16 cut therein, and the holes 17 of the diagonal ducts 16 are formed in the outer surface of the rotor 3. A main cooler 18 serves to cool down the cooling fluid 6 whose temperature is elevated as a result of having cooled parts of the turbine generator, and a sub cooler 19 is provided for the same purpose.
In the stator 2 are provided stator cooling ducts 13 in juxtaposition in the axial direction of the turbine generator.
According to this type of rotor as described above, there are defined the reverse zone 20 where the cooling fluid 6 flows through the stator cooling ducts 13 inwardly in the radial direction and the forward zone 21 where the cooling fluid 6 flows through the stator cooling ducts 13 outwardly in the radial direction.
The field coil 8 is made up of plural flat shaped conductors (not shown) stacked (laminated) one upon another, each having plural ventilation holes arranged in the axial direction, and the communicated ventilation holes make up the diagonal ducts 16 in the field coil 8. Further, ventilation holes are cut in each flat conductor in two rows arranged in the circumferential direction (i.e. direction parallel to the sheet of the drawing) so that the V-shaped diagonal ducts 16 in the field coil 8 are configured in a net shape.
The cooling fluid 6 forced out by the axial fan 5 first cools the end of the stator coil 14 and then flows into the sub cooler 19, where the temperature of the cooling fluid 6 is lowered. The chilled cooling fluid 6 out of the sub cooler 19 flows into the stator cooling ducts 13 in the reverse zone 20 to cool the iron core 12 and the stator coil 14, and is discharged into the air gap 11. Then, the cooling fluid 6 is conducted through the suction holes (holes) 17 into the diagonal ducts 16 and passes through the diagonal ducts 16 inwardly in the slanted direction to cool the field coil 8. Thereafter, the cooling fluid 6 changes its flow direction at the bottom of the field coil 8, flows outwardly in the slanted direction to cool the field coil 8 again, and is discharged at the discharge holes (holes) 10 into the air gap 11.
The cooling fluid 6 now flows from the air gap 11 into the stator cooling ducts 13 in the forward zone 21, cools the iron core 12 and the stator coil 14, and flows into the main cooler 18. The temperature of the cooling fluid 6 is lowered in the main cooler 18, and the chilled cooling fluid 6 returns to the axial fan 5 to complete the whole circulation.
The mechanism of the gap pick up diagonal flow cooling will here be described in reference to FIGS. 18A, 18B and 19.
FIG. 18A shows the structure of the suction hole provided in the rotor cooling duct 9, and FIG. 18B shows the structure of the discharge hole provided in the rotor cooling duct 9.
A cut 28 is formed in the suction hole 17 of the rotor cooling duct 9, and a projection 29 is formed downstream of the discharge hole 10 of the rotor cooling duct 9. Reference numeral 31 indicates a region for raising pressure defined in the suction hole 17, and numeral 32 denotes a region for lowering pressure defined behind the projection 29 at the discharge hole 10.
When the rotor 3 starts rotation, the circumferential flow of cooling fluid 6 is generated in the air gap 11. Since the cuts 28 are formed in the suction holes 17 in the circumferential direction, part of the cooling fluid 6 near the circumference of the rotor 3 is conducted in such a direction as to cause the fluid to collide with the inner walls of the suction holes 17. As the fluid approaches the inner walls, the static pressure of the fluid recovers with the result that the higher pressure regions 31 are formed in the suction holes 17. The symbol hi indicates the depth of the cut 28 of the suction hole 17.
On the other hand, since the projections 29 are formed downstream of the discharge holes 10, the circumferential flow of the cooling fluid 6 creates separation vortices behind the projections 29. As a result, the low pressure regions 32 are formed in the discharge holes 10. The symbol ho denotes the height of the projection 29.
The flow rate of the cooling fluid 6 flowing through the diagonal duct 16 in the rotor depends on the difference between the pressure in the higher pressure region and the pressure in the low pressure region. FIG. 19 shows in graphical representation the relationship between the flow rate Q and the pressure rise P. In FIG. 19, solid curve represents the Q-P characteristic which is similar to that applicable to a pump or a fan, and broken curve gives the pressure loss characteristic of the cooling fluid 6 distributed from the suction hole 17 to the discharge hole 10. The intersection between the Q-P characteristic curve and the pressure loss characteristic curve defines the operating point which determines the flow rate of the cooling fluid 6 through the diagonal duct 16.
In the structure of the rotor having the gap pick up diagonal flow cooling system, the flow rate of the cooling fluid 6 for cooling the field coil 8 is securely maintained by providing plural pairs of suction hole and discharge hole in the circumferential surface of the rotor 3 and forming the diagonal duct 16 between each pair of the suction hole and the discharge hole. This constitution allows the repetition of the unit structures each having the diagonal ducts 16, in the axial direction of the rotor shaft so that uniform cooling performance can be expected in the field coil 8 in the axial direction, which is advantageous in that the axial elongation of the rotor 3 and therefore the scale-up of the capacity of the turbine generator can be realized. On the other hand, the complexity in the employed shape of the cooling fluid ducts results in an increase in production man-hour of the rotor 3 and makes the reduction in cost difficult. Accordingly, this constitution is used only for large capacity machines having ratings of higher than 500 MVA.


The present invention is drawn to methods for effecting weight loss, e.g. in the treatment of obesity and related conditions, including conditions associated with and/or caused by obesity per se.

Overweight and obesity represent a rapidly growing threat to the health of populations worldwide. Obesity raises the risk of morbidity from hypertension, dyslipidemia, type 2 diabetes mellitus (T2DM), coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea and respiratory problems, and some cancers. Obesity is also associated with increased risk in all-cause and cardiovascular (CV) disease mortality. The risk is directly proportional to the degree of obesity in an individual, which is typically measured via the body to mass index, or BMI. BMI is typically measured in units of kg/m2. For example, the risk of developing morbidity due to any of the above is especially high in individuals with a BMI of 25 or greater. The biomedical, psychosocial, and economic consequences of obesity have substantial implications for the health and well-being of the person with obesity.
Diet and behavior modification have been shown to be useful in producing effective, but modest weight loss leading to amelioration of comorbid medical problems. Addition of weight loss medications reinforces behavioral strategies; however clinical challenges remain with the magnitude of weight reduction (up to ˜5% vs placebo) and the maintenance of the achieved weight loss. Some of the available treatments have limitations for long term use due to their gastro-intestinal (GI) adverse effects, others—due to central nervous system adverse effects. Therefore, there is a substantial opportunity and real need to develop weight loss medicines which will be more effective and better tolerated.
LIK066 is an inhibitor of the sodium-glucose co-transporter-1 (SGLT1) and sodium-glucose co-transporter-2 (SGLT2). The dual mechanism (renal and intestinal) to reduce re-absorption/absorption of glucose leads to loss of calories (calorie-loss enhancer). It also has the potential to reduce food intake via central mechanisms mediated by an increase in incretin hormones (glucagon-like peptide-1 (GLP-1) and peptide YY). In a Phase I study with normal and dysglycemic adults with BMI≥35 kg/m2, LIK066 150 mg once daily (qd) resulted in mean 5.7% placebo subtracted weight loss at 12 weeks. Although the weight loss effect of LIK066 is promising, over 90% of the participants in the study developed diarrhea as an adverse effect. This is a serious problem in its own right, as diarrhea can lead to serious health problems associated with dehydration, electrolytic imbalance, or malnutrition. It would be desirable to find a way to ameliorate or eliminate the serious side effect of diarrhea associated with administration of LIK066, The various embodiments of the present invention, described in more detail below, accomplish this objective through a novel method of administration of LIK to a patient in need.

SGLT1/2 inhibitor LIK066 for treating obesity


The present invention discloses a method of providing data redundancy for HLR, the method comprises: performing cutover for subscribers' data preserved in master HLRs into a redundant center HLR; preserving all successfully executed operation & maintenance commands which are associated with system data and said subscribers' data of the master HLRs during runtime of the master HLRs; transferring said operation & maintenance commands preserved in the master HLRs to the redundant center HLR; converting the received operation & maintenance commands into internal operation commands recognizable by the redundant center HLR, and loading them into a host machine of the redundant center HLR. The present invention enhances the conformity of the subscribers' data, and reduces the maintenance workload of the redundant center HLR and lowers the maintenance complexity.

With rapid growth of mobile subscribers and incessant development of communication techniques, the unit capacity of single HLR in mobile communication system has reached tens of thousands or even more. Since HLRs have stored subscription information of mobile subscribers, mobile services for all the subscribers will cease when the HLRs fail for a long period of time due to unforeseeable causes such as power failure, fire, earthquake or lightning strike, etc. Therefore, it is urgent to provide remote redundancy for the HLRs.
The redundancy for HLRs includes two aspects, one aspect is data redundancy simply for backup subscribers' data, the other is service redundancy which is based on the former aspect, i.e., when a master HLR breaks down, a redundant HLR is able to take over the services by means of signaling switchover according to the backup subscribers' data, so as to prevent the calling services from being interrupted at a maximum level.
The topology structures of data redundancy for HLRs are classified into two types. One is 1+1 redundancy solution, and the other is N+1 redundancy solution.
The so-called 1+1 redundancy solution is to provide a redundant HLR for each master HLR in the existing network so as to achieve real-time backup for external services. Though the 1+1 redundancy solution is able to take over the services seamlessly by adopting the redundant HLR when the master HLR fails, apart from some extremely important places, the application field of this solution is relatively limited in consequence of its high investment and low rate of utilization.
The N+1 redundancy solution is to set up a special redundant center HLR for providing redundancy for N master HLRs. In the N+1 redundancy solution, the redundancy can be further divided into compatible redundancy and non-compatible redundancy according to the result whether the master HLRs and the redundant center HLR belong to the same manufacturer. Because there are many HLR equipment providers, and different HLRs have different data saving formats and data processing methods, the compatible solution is more widely used. Since the N+1 compatible redundancy solution is unable to back up subscribers' dynamic data in real time, it will lead to the situation that the subscribers cannot act as the called party in a period of time after a failure has appeared and the services have been taken over. However, as one redundant center is able to back up data for a plurality of master HLRs made by different manufacturers, the return rate on investment of the N+1 compatible redundancy solution is relatively better, thus this solution is broadly adapted in the network.
At present, the N+1 compatible redundancy solution mainly has two types, one is a baseline synchronization solution, and the other is a BOSS (Business Operation Support System) increased command synchronization solution.
What is called the baseline synchronization solution is to output the data files containing all subscribers' subscription information, i.e., the service data baseline of subscriber, by the master HLRs periodically, then convert the format of these files automatically by the redundant center into the format recognizable by the redundant center HLR, and load the files into the redundant center HLR. Thereby, it will realize the synchronization of subscribers' data between the master HLRs and the redundant center HLR. As the baseline synchronization solution requires the master HLRs to output the service data baseline of all subscribers periodically, performance of the host machine of the redundant center HLR is affected greatly, and it takes quite a long time to perform conversion and synchronization for the subscribers' data, it is seldom used in practical engineering.
The BOSS increased command synchronization solution is to convert the successfully executed business operation commands which were formerly sent to the master HLRs for modifying the subscribers' subscription data according to the interface format of the redundant center HLR, and load the commands into the host machine in real time via the business operation interface of the host machine of the redundant center HLR. Thus, as long as the master HLRs and the redundant center HLR implement baseline synchronization for one time in initial state, the conformity of the subscribers' data between the master HLRs and the redundant center HLR will be guaranteed by means of this way to achieve the synchronization of the subsequent increased command or data.
Since the BOSS solution does not have any special requirements on the performance and function of the host machine of the redundant center HLR, and only needs to add converting function for operation commands of different manufacturers' formats in the BOSS, this solution is simple and is low cost because of low engineering work required. Therefore, the solution is widely used in the network and has gradually turned into a mainstream of N+1 redundancy solution.
However, only operation commands processed by the business hall can be synchronized automatically by the BOSS solution, a large number of other operation commands processed out of the business hall, such as the operation commands for setting a batch of subscriber services in a Local Maintenance Terminal (LMT) of HLR, and setting parameters of HLR in the system level, can merely be synchronized manually by the administrator in terms of the procedure. Therefore, the maintenance workload of this solution is heavy.

Method of providing data redundancy for home location register


A process is disclosed for treating water, such as wastewater, with air or oxygen-enriched air under alkaline conditions to decompose and remove acrolein and acrolein byproducts from the water and/or wastewater. The process is able to lower the concentration of acrolein and acrolein byproducts from water to a sufficiently low level suitable for discharge to a municipal sewer collection system with reduced occurrence of the decomposition by-products of acrolein converting back to acrolein in the water. One embodiment of the process treats contaminated water containing acrolein with air or oxygen-enriched air by sparging or bubbling air or oxygen-enriched air through the contaminated water. The contaminated water can be treated with air or oxygen-enriched air where the contaminated water is initially adjusted to a pH greater than 7.0 for a time to convert at least a portion of the acrolein to 3-hydroxypropanal to obtain fully treated water and prevent conversion of 3-hydroxypropanal back to acrolein.

Acrolein, an alpha, beta unsaturated aldehyde, is a highly soluble hazardous compound in water (Eisler, 2007, Bowmer et al., 1974). It is highly toxic to bacteria, algae, and aquatic life in water at concentrations between 0.02 mg/L and 2.5 mg/L (USEPA, 2008). It is used as a biocide and an herbicide to control growth of submerged and floating aquatic weeds and algae in irrigation canals and reservoirs, as well as being used to prevent or reduce growth of bacteria in pipes used in petroleum production (USEPA, 2008). It can also be inadvertently produced from the combustion of biodiesels and biofuels in soot or condensate. Acrolein readily reacts with water through a hydration reaction to produce various by-products including 3-hydroxypropanal, acrylic acid, and allyl alcohol (Callahan et al., 1981). This reaction is a potentially reversible reaction that could become the rate-limiting step in the overall removal of acrolein from water. The acrolein hydration by-products can persist in water if they are not directly treated. The rate of acrolein hydration reactions is influenced by pH; specific pH levels result in acrolein transforming to 3-hydroxypropanal and other by-products (UK, 2009).
The required time duration for acrolein reactions and breakdown in water ranges from several hours to a few days. When present in industrial wastewaters discharged to sewers, the extent of natural acrolein breakdown in water will depend on water temperature, pH, other chemicals present in the water, and travel time through the sewer system. Once dissolved in water, acrolein and its by-products do not volatilize out of solution readily (Bowmer et al, 1974). Even if low concentrations of acrolein reach municipal wastewater treatment plants, it can kill or severely inhibit bacterial activity and treatment capacity at those plants (Stack, 1957). Thus, the need for complete removal of acrolein and its byproducts from water and wastewater is well recognized in the wastewater treatment field (Kurian et al., 2001 U.S. Pat. No. 6,277,289 B1).
There are many methods identified for removing acrolein from water including membrane separation, activated carbon, ion exchange resins, and chemical addition. Roof and Reid, 1997 (U.S. Pat. No. 5,606,094) patented a method for directly scavenging acrolein from liquid or gaseous mixtures using sodium bisulfite (Roof and Reid, 1997). Ishida et al., 1975 (U.S. Pat. No. 3,909,408) patented a process for treating aldehydes from a gas or liquid mixture using an aqueous solution of sodium sulfite-sodium bisulfite agents at a solution pH of 6-11 standard units (s. u.). Lashley, 1975 (U.S. Pat. No. 3,923,648) patented a process for disposal of wastewater containing unsaturated aldehydes by maintaining the wastewater at a pH of at least 8 and a temperature between 25° C. and 100° C. (Lashley et al., 1975). Kurian et al., 2001 (U.S. Pat. No. 6,277,289 B1) patented a process for treatment of aqueous aldehydes and/or ketones by contact with organic diamines, triamines, tetraamines, polyamines, and/or inorganic ammonium compounds (Kurian et al., 2001).
Although the available methods, some of which are listed above, have varying degrees of success in degrading and removing acrolein from water; these methods all share the potential of degrading acrolein to its by-products without necessarily removing these by-products during treatment. By not removing acrolein's by-products in water, depending on prevailing pH conditions of the treatment process, acrolein can transform into one of its hydration by-products (e.g., 3-hydroxypropanal) and pass through treatment unchecked, only to revert back to the parent compound (acrolein) at a later time when different pH conditions occur. This reverse reaction can re-introduce acrolein into the treated water stream after it passed through the treatment process, causing elevated/hazardous acrolein concentrations to be discharged into the environment. There remains a need today in industrial applications for a treatment process that effectively and consistently removes both acrolein and its by-products. The objective of the present invention is to promote the degradation of acrolein and its reversible by-products to effectively, substantively and permanently remove acrolein and its by-products, (e.g., 3-hydroxypropanal, acrylic acid, and allyl alcohol) from water.

This patent is subject to a terminal disclaimer.

Treatment of acrolein and acrolein by-products in water and/or wastewater


A multi-layer article comprises a substantially non-fluorinated layer, and a fluorinated layer of fluoropolymer comprising interpolymerized monomeric units derived from one or more of hexafluoropropylene and tetrafluoroethylene monomers, one or more non-fluorinated olefinically unsaturated monomer, and substantially no vinylidene fluoride monomer. The multi-layer article further comprises an aliphatic di-, or polyamine which provides increased adhesion between the layers as compared to a multi-layer article not containing the aliphatic di-, or polyamine. The multi-layer article can be prepared by mixing the aliphatic di-, or polyamine into the substantially non-fluorinated polymeric material, or by applying the aliphatic di-, or polyamine to a surface of one or more of the substantially non-fluorinated polymeric material or the fluoropolymer, and thereafter preparing a multi-layer article.

Fluorine-containing polymers (i.e., fluoropolymers or fluorinated polymers) are a commercially important class of materials. Many fluoropolymers are known to exhibit high thermal stability and usefulness at high temperatures, as well as extreme toughness and flexibility at very low temperatures. Many fluoropolymers are also almost totally insoluble in a wide variety of organic solvents, and resistant to many chemical compounds that might degrade other classes of less resistant materials. Additionally, many fluoropolymers are recognized for their barrier properties; i.e., their ability to prevent the passage of liquids or vapors.
Increased concerns with evaporative fuel standards have led to a need for fuel system components that have improved barrier properties, to minimize the permeation of fuel vapors through automotive components such as fuel filler lines, fuel supply lines, fuel tanks, and other components of a automobile emission control systems. Multi-layer articles such as multi-layer tubing have been used within these applications. These multi-layer products can comprise a fluorinated layer, which provides an inert, vapor barrier, and one or more other layers that can add strength, rigidity, or other mechanical properties to the multi-layer article. As an example, some multi-layer articles include a fluorinated layer and a layer comprising a substantially non-fluorinated polymer.
To be most useful, these multi-layer articles should not delaminate during use. That is, the adhesive bond strength between the different layers of the multi-layer article should be sufficient to prevent the different layers from separating. A variety of methods have been employed to increase the adhesive bond strength between a layer comprising a fluoropolymer and a layer comprising a substantially non-fluorinated polymer. For example, a layer of adhesive can be added between the two layers. As an alternative to or in addition to adhesives, surface treatment of one or both of the layers has been used to increase the adhesive bond strength between the two types of layers. For example, layers comprising a fluoropolymer have been treated with charged gaseous atmosphere followed by application of a layer of thermoplastic polyamide. As another approach, "tie-layers" have been used to increase the adhesive bond strength between a fluoropolymer and layer comprising a substantially non-fluorinated polymer. A tie layer is a layer comprising a blend of materials from two dissimilar layers disposed between the two dissimilar layers. See e.g., European Patent Application 0523644 (Kawashima et al.).
The adhesion between a substantially non-fluorinated polymer and a fluoropolymer, wherein the fluoropolymer is derived from vinylidene fluoride (VDF) and hexafluoropropylene (HFP), has been found to increase upon exposure of the fluoropolymer to an amine compound. Fluoropolymers derived from VDF and HFP are relatively susceptible to attack by basic materials due to the presence of an electronegative, carbon-bonded, electron-withdrawing --CF.sub.3 group (from the HFP) adjacent to a carbon-bonded hydrogen atom provided by the VDF monomer. Amines can therefore be reacted with the VDF/HFP fluoropolymer to increase adhesion of a fluoropolymer to a substantially non-fluorinated substrate.
On the other hand, fluoropolymers derived from fluorinated monomers that include substantially no VDF are known to exhibit superior inertness relative to fluoropolymers derived from VDF monomers, and are consequently more resistant to chemical attack. These fluoropolymers are expected to be inert from attack by a base, and are therefore less apt to undergo adhesion-promoting reactions with amines. Examples of such fluoropolymers include fluoropolymers derived from monomers comprising tetrafluoroethylene (TFE) and/or hexafluoropropylene (HFP), and substantially no vinylidene fluoride monomers.
What is needed, but not provided by the prior art is a method of increasing the adhesive bond strength between a substantially non-fluorinated polymeric material and a fluoropolymer, the fluoropolymer being derived from one or more of TFE and HFP monomers, and one or more non-fluorinated olefinically unsaturated monomers, but substantially no vinylidene fluoride monomer.

Multi-layer compositions comprising a fluoropolymer

Minnesota Mining and Manufacturing Company


A serial interface for a programmable logic device supports a wide range of data rates by providing a first number of channels supporting a first range of data rates and a second number of channels supporting a second range of data rates. The first range of data rates is preferably lower than the second range of data rates and preferably the first number of channels is higher than the second number of channels which preferably is 1. For backward compatibility with existing devices, the first number of channels in each interface preferably is four. Each channel preferably includes a physical medium attachment module and a physical coding sublayer module. Each of the higher-speed channels in the second number of channels preferably also includes a clock management unit, while the lower-speed channels in the first number of channels preferably share one or more clock management units.

This invention relates to a high-speed serial interface, especially in a programmable logic device (PLD), which may operate at different data rates.
It has become common for PLDs to incorporate high-speed serial interfaces to accommodate high-speed (i.e., greater than 1 Gbps) serial I/O standards—e.g., the XAUI (Extended Attachment Unit Interface) standard. In accordance with the XAUI standard, a high-speed serial interface includes transceiver groups known as "quads," each of which includes four transceivers and some central logic.
In one implementation, each transceiver is divided into a physical medium attachment (PMA) portion or module which communicates with outside devices, and a physical coding sublayer (PCS) portion or module which performs serial processing of data, for transmission to, or that is received from, those outside devices. Currently available PMA modules and PCS modules overlap in terms of the data rates that each will support, but the maximum data rate of available PMA modules exceeds the maximum data rate of available PCS modules.
In any event, heretofore the maximum data rate that could be supported in a programmable logic device high-speed serial interface has been about 6 Gbps to about 6.5 Gbps. However, serial communications standards at speeds up to about 10 Gbps have begun to emerge.
It would be desirable to be able to support currently available data rates in a programmable logic device serial interface.

Multiple data rates in integrated circuit device serial interface


This curtain-type airbag apparatus is provided with: an airbag which is arranged along a top edge of a vehicle body and develops in a curtain-shape manner along an inside of a window; and an inner cover which covers a vehicle interior side of the airbag. The inner cover is supported by the vehicle body via a hinge member having a reversed U-shape.

Priority is claimed on Japanese Patent Application No. 2006-174013, filed Jun. 23, 2006, and Japanese Patent Application No. 2006-314103, filed Nov. 21, 2006, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a curtain-type airbag apparatus and an airbag module which develop an airbag in a curtain-shape manner along an inside of a window of a vehicle.
2. Description of the Related Art
A curtain-type airbag apparatus which develops an airbag in a curtain-shape manner along an inside of a window of a vehicle, is provided with an airbag which is arranged along a roof side rail being a top edge of a window and has a vehicle interior side covered with an inner cover, while in an accommodated state thereof. The developing airbag develops while pressing the inner cover to open it. A conventional art is proposed in which: a deformable thinner portion is formed in the inner cover itself in order to enable easy opening thereof; and a portion lower that the thinner portion is rotated by pressing force of the airbag (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2004-291859 (hereinafter "Patent Document 1")).
In the case in which a round-shaped design is employed for the roof side rail being the top edge provided with the airbag, the inner cover and the thinner portion formed therein have to employ the round-shaped design also; however, such design is not suitable for an opening operation of the inner cover (i.e., not suitable for enabling a smooth rotation of the portion lower than the thinner portion). That is, the linear-shaped thinner portion enables easy rotation of the lower portion, while the round-shaped thinner portion makes the easy rotation harder. Accordingly, in order to prevent this problem, a slidable inner cover may be employed; however, such construction needs a comparatively large device for sliding the inner cover, and also disables obtaining a large opening through which the airbag develops. In addition, the above-mentioned Patent Document 1 discloses a construction in which: the vehicle interior side and the vehicle exterior side of the airbag are covered with covers to form a module; and the module is installed in a vehicle body by clips provided on the vehicle exterior side of the cover. However, such installation structure disables securing sufficient rigidity for maintaining the shape of the module.
Accordingly, the present invention has an object of providing: a curtain-type airbag apparatus which enables a smooth opening of an inner cover by a developing airbag with a wide opening, even in the case in which the airbag is arranged along a top edge of a round-shaped window; and an airbag module which enables increasing the high rigidity for maintaining the shape thereof.

Curtain-type airbag apparatus and airbag module


A test apparatus for generating a test case based on a fault injection technique and a method of controlling the same are disclosed. The method includes identifying at least one function in a program to be tested based on a software detailed design, generating a test design document based on fault location that can be generated in connection with the identified at least one function and a fault type to be injected into the fault location, searching for the fault location to be injected based on the generated test design document and source code of the program, determining a fault injection scheme and the fault type, and predicting a result by applying a fault injection corresponding to the fault injection scheme and the fault type into the searched location to generate a test case.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
ISO 26262, which is a vehicle functional safety standard, recommends a fault injection test (FIT) as a method of determining whether a safety mechanism is properly operated at the time of unit and integrated tests of software. However, there is limitation in securing reliability of the fault injection test for verifying the functional safety of software only through standardization of requirements on functional safety of software for vehicles.
A method capable of generating a test case by applying a software design document and a safety requirements document derived in a design step at the time of performing a fault injection test of software for vehicles may be desired.

Vehicle function test apparatus and method of controlling the same

Ewha University—Industry Collaboration Foundation


A pallet having wooden boards secured together by nails which achieve approved operating characteristics. The nail is embodied in a package secured together by a pair of parallel wires welded to the shanks. Each nail having a shank diameter between 0.078 in. and 0.085 in., each nail is manufactured from steel wire and has a length between 1.50 in. and 2.25 in. The ratio of the head diameter to the shank diameter of each nail is between 2.70 and 3.37.

The above-identified application relates to packaged nails suitable for pallet constructions.
Pallets are conventionally constructed of wood boards. An example of a typical pallet is formed in three layers. The bottom layer includes three parallel boards of a size, for example, of ¾″×3″ oriented with the larger disposed sides horizontally. The middle layer includes heavier boards of a size, for example, of 1¼″×3⅜. These boards are oriented with the larger sides disposed vertically and disposed with their longitudinal extent extruding perpendicular to the longitudinal extent of the bottom boards. These heavier middle boards may be recessed along their lower surfaces between the bottom boards to accommodate the forks of a conventional fork lift truck. The top layer may include a series of parallel boards like those of the bottom layer, as for example, seven, oriented in the same way as the bottom layer but more closely spaced. Typically, the boards are held together by nails. In many cases, these nails are packaged as dual wire mounted coils in a form to be driven by a pneumatically actuated fastener driving device. Typically, two nails are driven through each of the bottom and top boards into each of the three heavier middle boards.


A liquid crystal device comprises a nematic liquid crystal, voltage means for applying a voltage across said liquid crystal, and two substrates (42, 30) each provided with an alignment layer (32, 33), wherein: said liquid crystal is sandwiched between said two substrates (42, 30); said nematic liquid crystal can be placed in at least one operating state and at least one non-operating state, and at least one of said alignment layers (32, 33) is provided with a plurality of surface protrusions (40) formed from an anisotropic material.

1. Field of the Invention
The invention relates to nematic liquid crystal devices formed with anisotropic protrusions, and methods of production. thereof.
2. Description of the Related Art
The invention can be used to provide an improvement in obtaining and if necessary isolating the operating state of a pi-cell liquid crystal device at low voltages. The invention can also be applied to nucleating the operating states from the globally stable states in the BTN device, and for isolating the operating states from each other and from the globally stable state.
The invention is particularly applicable to flat panel displays and pi-cells used in LCTV. Another application is in using BTN displays in mobile products.
P. D. Berezin, L. M. Blinov, I. N. Kompanets and V. V. Nikitin 'Electro-optic Switching in Oriented Liquid-Crystal Films' July-August 1973 Sov. J. Quant. Electron Vol. 3, pp. 78-79 is a paper which describes the achievement of fast nematic liquid crystal response times obtained in low surface tilt, non-twisted cells. It is unclear from the paper whether the alignment directions at the two surfaces are parallel or anti-parallel. The fast switching times were achieved by applying a bias voltage such that the optical modulation is mostly caused by reorientation of the liquid crystal molecules near the surface region, whilst those in the bulk remained substantially homeotropic. (See for example lines 11-19, column 1, page 79, together with lines 14-17, column 2, page 78)
P. J. Bos and K. R. Koehler/Beran 'The pi-Cell: A Fast Liquid Crystal Optical Switching Device' 1984 Mol. Cryst. Liq. Cryst. Vol. 113, pp. 329-339 is a paper which introduces the pi-cell as a liquid crystal display mode that is fundamentally fast, since the symmetry of the device eliminates the adverse effects of a flow induced "backwards" torque exerted on the liquid crystal director towards the cell centre. The pi-cell has parallel surface tilt (the term "parallel" here referring to the rubbing directions at the two cell surfaces, rather than to the directors) such that at low voltages the splay (or H-) state is stable (see FIG. 3b, page 332). At higher voltages switching takes place between a high and low voltage bend (or V-) state (see FIG. 2b, page 331).
U.S. Pat. No. 4,566,756 describes a pi-cell doped for d/p>0.25. As a result of the doping this device does not form the H-state at low voltages and remains in the T-state, not the V-state at high voltages. However at high voltages the T-state has similar optical properties to that of the V-state. This mode then overcomes the nucleation problems of the conventional pi-cell and demonstrates similar optical characteristics at high voltages. Unfortunately at lower voltages the effect of the inherent twist on the optical characteristic gives a poorer performance than the conventional pi-cell.
EP 0,996,028 describes the generic use of nucleation regions to initiate the growth of the V-state from the H-state. Particular examples are given of the pi-cell device and the complementary negative pi-cell or SBD. As well as teaching patterned surface pre-tilt to generate these nucleation regions, it also teaches in-situ polymerisation of a nucleation region e.g. in the inter-pixel gaps. One technique described for patterning surface tilt is to use patterned reactive mesogen layers. These are however thin and do not protrude considerably into the liquid crystal.
EP 0,965,876A2 describes the use of substantially homeotropic alignment to surround the active pixel area within a conventionally low surface pretilt pi-cell based display. At zero volts the surrounding substantially homeotropic alignment isolates the pixel from the reformation of the H-state, at zero volts then the pixel relaxes into the twist state (T-state) (see abstract column 2, page 3, lines 39-44 and claim 1). The device is operated at higher voltages in the V-state.
Japanese Patent Application JP-A-9 90432 (Toshiba) discloses the provision of nucleation sites within a pi-cell panel. The nucleation sites are provided by including spacer balls or pillars within the pi-cell panel and cooling the liquid crystal material from an isotropic phase to a nematic phase while an electric field is applied across the panel. This results in some of the spacer balls or pillars acting as nucleation sites for growth of the V-state. However the positioning of the spacers cannot be easily controlled.
Japanese Patent Application JP-A-9 218411 (Sekisui) discloses a LCD having a bend alignment state, which is stabilised, in the absence of an applied field, by the presence of spacers in the form of spherical particles The spacers have a surface energy such that liquid crystal molecules adjacent the alignment layers are mainly aligned parallel to the alignment layers. However, in order for this technique to work, a field has to be applied during the initial alignment of the device. Also, the particles can not be positioned so as to be outside the pixel apertures so that the contrast ratio of the display is reduced by the presence of the particles.
European Patent Application No. 00310110.2 describes the use of birefringent spacers (for example those made from polymerisable reactive mesogens) in a liquid crystal display, said spacers having the same optical characteristic as one of the states of the switched states of the liquid crystal display.
DE 2,849,402A1 describes a display with both variable and invariable parts. The variable parts are liquid crystal, whilst the invariable parts are fabricated from a birefringent material running between the top and bottom surfaces. These invariable parts act also as spacers.
British Patent Application No. 9704623.9 describes a liquid crystal device in which at least one alignment layer has been fabricated from a mixture of mono-functional and di-functional reactive mesogens, the ratio of these materials acting to control the surface pre-tilt of the contiguous liquid crystal material. It teaches that as the percentage of mono-functional reactive mesogen is increased then the tilt at the RM/air interface is increased.
U.S. Pat. No. 5,995,184 describes the fabrication of thin film retardation plates from polymerisable reactive mesogens. It teaches the addition of an additive that migrates to the RM/air interface to modify the surface energy and hence control the tilt of the reactive mesogen molecules at that surface, in particular it teaches reducing the tilt angle at the RM/air interface.
EP 0,880,052 describes the fabrication of multi-domain liquid crystal devices by using a patterned, thin, twisted reactive mesogen layer above a conventional alignment layer. Although FIG. 5 of the British Application (9710481.4) shows parallel alignment in the none reactive mesogen region and twisted alignment above the reactive mesogen region, the regions above the reactive mesogen are not used for nucleating an operating state from a zero voltage non-operating state. This is additionally supported by the regions above the RM being of the same area as regions not above the RM, and that the application explicitly teaches to make the RM layer as thin as possible.
EP 0,018,180 and Journal of Applied Physics Vol. 52, No. 4, p. 3032 (1981) disclose the basic operating principle of the bistable twisted nematic (BTN) device i.e. switching between two metastable states of twist angle ±180°, a state of angle ° being the globally stable state not being used. These also disclose the use of isolation by the reduction of cell thickness in the unaddressed regions. A BTN device is a slower device than a pi-cell, but is stable in the two states of 100 ±180°, hence the name bistable. A typical BTN device is referred to as having antiparallel alignment because the rubbing directions at the two liquid crystal surfaces are anti-parallel. This actually results in the directors at the two surfaces of the liquid crystal being aligned parallel to each other.
British Patent Application No. 9911730.1 describes the fabrication of BTN devices with an isolation region between neighbouring pixels, the isolation region is a HAN state, a uniform lying helix or a focal conic texture. It is formed through patterning the surface pretilt of the alignment layer, such that the pretilt of interpixel gaps is different from that of the intrapixel region.
The antiparallel BTN has three possible stable twist states e.g. 0°, 180° and 360°, more generally: (phi−pi), phi and (phi+pi) twist states. With suitable addressing, two of these states can be accessed and used as operating states. The energy of the three stable twist states depends on the thickness-to-pitch (d/p) ration and differs, such that the lowest energy state, which is normally topologically distinct to the other two stable twist states, does not correspond to an operating state, e.g. phi. This results in the energetically favourable (but undesirable) state nucleating and growing over a period of time once the voltage is turned off. Even if this undesired state does not nucleate when the voltage is turned off, bistability is not possible without isolation because the more energetically favourable of the operating states will slowly grow into the other one.

Nematic liquid crystal devices comprising surface protrusions formed of anisotropic material for nucleation of an active region


The present invention thus provides a plastic part with a surface area of a semi-rigid sheet material such as metal, wood or wood-based paper product and a novel process where the sheet material edges are covered with a second plastic component that adheres both to the sheet material and to the first plastic material. A first plastic substrate component is prepared with an adhered sheet material surface area and then the edges of the sheet material are overlapped by a second molded-on, plastic edge-covering component. A preferred sheet material laminate structure is also provided with a backing layer that protects an interior adhesive layer. The second molded-on edge-covering component covers the sheet material edge to provide an aesthetically pleasing surface. This construction produces a more durable sheet material edge covering and eliminates the tendency of the sheet material to peel off the molded part during use.

There are a number of processes for providing a surface layer or surface insert of a metal, wood or paper, onto the surface of molded plastic parts using an injection molding process and pre-inserting or feeding a metal and/or wood surface piece in front of or into the mold. In U.S. Pat. No. 5,837,086 a metal foil layer is provided in an injection molded article. The metal foil is in a laminate with layers of plastic on either side. The laminate is placed in an injection mold and molten plastic forced against the plastic laminate surface.
EP 1,132,189 describes the application of a metallic foil surface layer to an injection molded plastic substrate in a process which conforms the metal surface layer to the mold and folds the metal edges back over the plastic edges to conceal the substrate and provide mechanical connection of the metal to the substrate. An adhesive layer may be applied between the foil and the substrate to assist in forming a secure connection.
DE 42 28 283 describes the use of insert molded plastic to cover the edges of a decorative layer of fabric or plastic film.

Molded parts with metal or wood surface areas and processes for their production


A method (300) and arrangement for LZ1 compression of a data string where multiple input symbols are compared in parallel with the history buffer by: holding in an input buffer (140) a first sequence of bytes of the data string; holding in a history buffer (110, 120) a second sequence of bytes of the data string; comparing (170), in matrix comparison means coupled to the input buffer and the history buffer and having a plurality of rows and columns of comparison units (200), bytes held in the input buffer with bytes held in the history buffer, bytes of the history buffer being coupled to diagonally displaced comparison units in the matrix comparison means; detecting (150) in each of the rows the column in which a largest number of consecutive byte matches has occurred at the comparison unit in that row and preceding comparison units in the same column; and encoding (160) as a token a sequence of matched bytes detected in the step of detecting (150).

The Lempel-Ziv algorithms are well known in the field of data compression. In particular, the "history buffer" version, known as LZ1, has become particularly popular in hardware implementations wherever lossless compression of coded data is required, since its relatively modest buffer requirements and predictable performance make it a good fit for most technologies.
The LZ1 algorithm works by examining the input string of characters and keeping a record of the characters it has seen. Then, when a string appears that has occurred before in recent history, it is replaced in the output string by a "token": a code indicating where in the past the string has occurred and for how long. Both the compressor and decompressor must use a "history buffer" of a defined length, but otherwise no more information need be passed between them.
Characters that have not been seen before in a worthwhile string are coded as a "literal". This amounts to an expansion of the number of bits required, but in most types of data the opportunities for token substitution (and hence compression) outweigh the incompressible data, so overall compression is achieved. Typical compression ratios range from 2:1 to around 10:1.
Some variations of the basic LZ1 algorithm have emerged over the years, but improvements have been incremental.
As the LZ1 algorithm works on units of a byte, traditional hardware implementations consider just one byte at a time when compressing the input stream. As each byte is input, the "history buffer" is scanned—using, for example, a Content-Addressable-Memory (CAM)—for all occurrences of the byte. As a single byte is not considered an efficient candidate for string replacement, any matches found must be supplemented by consecutive matches before token substitution takes place.
Each subsequent byte that is input is also sought in the history buffer, but the only matches reported are those following existing matches. Finally, the string match may terminate (when no more matches found that adjoin known matches) and the surviving "string match" is coded for substitution. The longer the match, the greater the saving in bits.
A simple implementation of the LZ1 algorithm which processes one byte per clock cycle is limited to some 100–200 MB/s at typical clock rates for current ASIC (application specific integrated circuit) technology. However, this may be insufficient for some applications (such as, for example, memory compression, optical networks and RAID disk arrays) which require high bandwidth for a single data stream. To increase performance, that is, the number of bytes that may be compressed per second, either the "cycle time" (the time taken to input the byte and find all matches) must be reduced, or the CAM be modified to search for more than one byte at a time. Because of the difficulty of designing multiple-input CAMS, performance improvements have usually concentrated on shortening the access time of the CAM, and hence the cycle time. But of course, the two improvements are not mutually exclusive; a multi-byte CAM will gain performance over and above any reduction in cycle time.
A previous attempt at more than one byte per cycle compression may be found in U.S. Pat. Nos. 5,771,011 and 5,929,791 (the latter being a divisional of the former), which match two bytes per cycle. Although these patents purport to indicate the steps necessary to extend their technique to more than two bytes, their teaching is incomplete and unrealisable as to how this is to be done: although they give a formula for the number of equations required in their technique for N bytes per cycle compression, they do not indicate how the equations themselves are to be derived. Nor do they reveal how a 'circular buffer' that is used can be adapted to handle larger numbers of input bytes per cycle.
An earlier U.S. Pat. No. 5,179,378 uses a different technique for comparing an input byte with a history buffer. Rather than inputting one byte at a time and employing a full parallel comparison (comparing that byte with the entire contents of the history buffer) each clock cycle, as in the above prior art patents, U.S. Pat. No. 5,179,378 breaks the comparison down into stages using 'systolic array' pipelining. However, the technique of this patent does not achieve a processing rate of more than one input byte per cycle, and may not even complete processing of one byte per cycle.
A need therefore exists for a method and arrangement for data compression wherein the above-mentioned disadvantage(s) may be alleviated.

Method and arrangement for data compression according to the LZ77 algorithm

International Business Machines Corporation


A semiconductor integrated circuit device has an interconnection structure in which multilayer aluminum interconnection layers are connected through a connection hole. A first aluminum interconnection layer is formed on a main surface of said semiconductor substrate. An insulating layer is formed on the first aluminum interconnection layer and has a through hole extending to a surface of the first aluminum interconnection layer. A second aluminum interconnection layer is formed on the insulating layer and is electrically connected to the first aluminum interconnection layer through the through hole. The second aluminum interconnection layer includes a titanium layer, a titanium nitride layer and an aluminum alloy layer. The titanium layer is formed on the insulating layer to be in contact with the surface of the first aluminum interconnection layer through the through hole. The titanium nitride layer is formed on the titanium layer. The aluminum alloy layer is formed on the titanium nitride layer. An electrical contact resistance between the first and second aluminum interconnection layers is stabilized, and resistance against the electron-migration and stress-migration is improved in the interconnection structure.

1. Field of the Invention
The present invention relates generally to interconnection structures of semiconductor integrated circuit devices and a manufacturing method therefor, and more particularly to an interconnection structure of a semiconductor integrated circuit device in which multilayer aluminum interconnection layers are mutually connected through a connection hole, and to a manufacturing method therefor.
2. Description of the Prior Art
In general, a semiconductor device comprises a semiconductor substrate and elements such as transistors formed thereon. Various interconnection layers are formed on the semiconductor substrate for electrically connecting these elements to each other and to an external circuit(s). These interconnection layers have been formed of polysilicon films, high melting point metal films, high melting point metal silicide films, aluminum films and aluminum alloy films. In recent years, reduction of the interconnection layer resistance has been required in the semiconductor integrated circuit devices which are highly integrated for high speed operations. Therefore, the semiconductor integrated circuit devices essentially require aluminum multilayer interconnection structure formed of aluminum films or aluminum alloy films having a small resistivity. An example of the conventional aluminum multilayer interconnection structure is disclosed in "High Performance Multilevel Interconnection System with Stacked Interlayer Dielectrics by Plasma CVD and Bias Sputtering", M. Abe et al, pp. 404-410, VMIC conference 1989.
FIG. 6 is a partial sectional view showing an example of an aluminum multilayer interconnection structure in the conventional semiconductor integrated circuit device. In the figure, a silicon semiconductor substrate 1 bears DRAM (Dynamic Random Access Memory) cells 2 which are formed in a stacked cell structure. A base insulator film 3 is formed on the DRAM cells 2. First aluminum interconnection layers 4 are formed on the base insulator film 3 with predetermined spaces between each other. The first aluminum interconnection layers 4 are covered with an interlayer insulating film 5, which is provided with connection holes 6 (also called as "via-holes" or "through-holes"). Second aluminum interconnection layers 7 are formed on the interlayer insulating film 5 and are connected to the first aluminum interconnection layers 4 through the connection holes 6. A protection insulator film 8 is formed to cover the DRAM cell 2, first aluminum interconnection layers 4 and second aluminum interconnection layers 7 to protect them against moisture and other external material from entering.
In the conventional aluminum multilayer interconnection structure shown in FIG. 6, yield and reliability of the semiconductor device technically depend on stability of a connection part (hereinafter called "via-hole part") between the first aluminum interconnection layer and the second aluminum interconnection layer. A manufacturing method of the conventional aluminum multilayer interconnection structure shown in FIG. 6 will be described particularly with respect to formation of the via-hole part. The multilayer interconnection structure has been generally formed of a combination of polysilicon wirings, high melting point metal wirings, high melting point silicide interconnection layers and aluminum wirings. However, the following discussion is made with respect to an aluminum two-layer structure in which both interconnection layers in the first and second layers are aluminum interconnection layers.
FIGS. 7A-7G are partial sectional views showing, in accordance with manufacturing steps, a manufacturing method for the aluminum two-layer interconnection structure in the conventional semiconductor integrated circuit device.
Referring to FIG. 7A, the DRAM cell 2 is formed on a surface of the silicon semiconductor substrate 1. The DRAM cell 2 is formed of an element separator oxide film 301, a transfer gate electrode 302, an impurity diffusion layer 303, a word line 304, a memory node 305, a capacitor insulator film 306, a cell plate 307 and an insulator film 309.
Referring to FIG. 7B, the base insulator film 3 is formed on an entire surface of the silicon semiconductor substrate 1, on which the DRAM cell 2 has been formed. Then, photolithography and etching technique are used for forming a contact hole 308 at a predetermined position in the base insulator film. The first aluminum interconnection layer 4 is formed as a bit line and electrically contacts with the impurity diffusion layer 303 through this contact hole 308.
Recently, a semiconductor integrated circuit device in which sizes of elements are reduced to an order of submicron has employed the interconnection layer in which a barrier metal film 310, e.g., of titanium nitride (TiN) or titanium-tungsten (TiW) and an aluminum alloy film 311 of Al-Si-Cu or others are combined. The aluminum interconnection layer having such structure has been used for the following reasons.
(1) If the aluminum is in direct contact with the silicon substrate (impurity diffusion layer) at the contact part, an abnormal reaction (i.e., alloy spike) is locally caused. This produces a reaction layer which breaks through a region of the impurity diffusion layer and extends downwardly in the silicon substrate, resulting in a junction leak at the impurity diffusion layer. In order to prevent this, the barrier metal film is formed in direct contact with the silicon substrate (impurity diffusion layer).
(2) Silicon in the aluminum alloy film is deposited at the contact part due to the solid-phase epitaxial growth, which causes imperfect contact. In order to prevent this, the barrier metal film is formed under the aluminum alloy film.
(3) Upper layers such as an interlayer insulating film and protection insulator film are formed over the aluminum interconnection layer. A film stress by these upper insulator films may break the aluminum interconnection layers. In order to increase the resistance against such stress migration phenomenon, the barrier metal film is formed under the aluminum alloy film.
A film forming the first aluminum interconnection layer 4 is usually formed by deposition in a sputter method and subsequent patterning thereof, using the photolithography and etching.
Structures in which the first aluminum interconnection layer is formed of a stacked layer structure of a titanium film, a titanium nitride film and an aluminum contained film are disclosed in the Japanese Patent Laying-Open Nos. 64-59937 (1989) and 61-90445 (1986).
Referring to FIG. 7C, the interlayer insulating film 5 is formed on the whole surface of the first aluminum interconnection layer 4. This interlayer insulating film 5 is formed of a combination of a silicon oxide film 321 formed by, e.g., the CVD (Chemical Vapor Deposition), an inorganic application insulator film 322 and a silicon oxide film 323 formed by the CVD.
The silicon oxide film 321 is formed by the CVD utilizing a heat and a plasma at a formation temperature of 300.degree.-450.degree. C., using a mixture of on one hand a silane (SiH.sub.4) gas and on the other hand an oxygen (O.sub.2) gas or a dinitrogen monoxide (N.sub.2 O) gas. Recently, a silicon oxide film has been formed from an organic silane contained material such as TEOS (Tetra-Ethyl-Ortho-Silicate) characterized by a good step coverage.
The inorganic application insulator film 322 formed for flattening generally includes silanol (Si(OH).sub.4) or the like as a main component. After rotary application of material including the silanol or the like as a main component, baking is carried out at a temperature of 400.degree.-450.degree. C. for changing it to a silicon oxide film, whereby the surface of the silicon oxide film 321 formed by the CVD is flattened. Since this inorganic application insulator film 322 has a high hygroscopic property, it may cause a disadvantage such as gas emission if the insulator film 322 is exposed at a side wall of the via-hole part. Therefore, an etchback processing using dray etching by a fluorine contained gas or argon gas is effected on this inorganic application insulator film 322 so as to prevent the exposure of the surface of the inorganic application insulator film 322 at the side wall of the via-hole part.
A silicon oxide film 323 is formed on the inorganic application insulator film 322 in a manner similar to that for forming the silicon oxide film 321.
Referring to FIG. 7D, the connection hole 6 is formed by the photolithography and etching to expose a predetermined surface area of the first aluminum interconnection layer 4. This step is carried out as follows.
A photoresist 324 is provided to cover an area except for that in which the connection hole 6 is formed by the photolithography. Then, the interlayer insulating film 5 is selectively removed by a taper etching method to open the connection hole 6. The taper etching method is a combination of wet etching by a fluorine contained solution and reactive ion etching using a mixture of gases of CHF.sub.3 and O.sub.2 as main components.
The photoresist 324 as well as a reaction product and others produced in the etching are removed by an oxygen (O.sub.2) plasma and a wet chemical processing after the etching.
Referring to FIG. 7E, in the step for forming the connection hole 6, the surface of the first aluminum interconnection layer 4 is exposed to a plasma of a fluorine contained gas such as CHF.sub.3 and/or an oxygen gas so that a deterioration layer 201 of aluminum which includes fluoride and oxide is formed at a thickness of about 100 .ANG. on the surface of the first aluminum interconnection layer 4 in the connection hole 6. Therefore, in order to remove an insulator film, i.e., the thin deterioration layer of the aluminum and to obtain a stable contact resistance, sputter etching using an argon ion (Ar.sup.+) 202 is effected prior to the formation of the second aluminum interconnection layer.
Then, as shown in FIG. 7F, the second aluminum interconnection layer 7 is continuously deposited in a vacuum, using the sputter method. This second aluminum interconnection layer 7 is a film of aluminum alloy such as Al-Si, Al-Si-Cu or Al-Cu. This film is formed by the patterning, using the photolithography and etching in a manner similar to that for the first aluminum interconnection layer.
After the formation of the second aluminum interconnection layer 7, heat treatment is carried out at a temperature of about 400.degree.-450.degree. C. so as to electrically contact the first and second aluminum interconnection layers 4 and 7 together in the connection hole 6.
Finally, as shown in FIG. 7G, the protection insulator film 8 such as a silicon oxide film or silicon nitride film is deposited on the second aluminum interconnection layer 7 by the CVD so as to protect the semiconductor elements and interconnection layers against the moisture and other entering from the external.
The aluminum multilayer interconnection structure of the prior art has the following problems.
Due to the miniaturization of the wiring, the diameter of the connection hole 6 has been reduced. If the diameter of the connection hole 6 is at a sub-micron level, a problem may be caused with respect to stability and reliability in the electrical connection at the contact hole 6.
In the prior art, as described above, the sputter etching is effected by the argon ion prior to the formation of the second aluminum interconnection layer 7. In this etching, as shown in FIG. 8A, an argon ion 202 removes a deterioration layer 201 (a layer including the fluoride and oxide of the aluminum) formed on the surface of the first aluminum interconnection layer 4 in the connection hole 6. In the conventional structure in which the contact hole 6 has a relatively small aspect ratio (B/A) less than 1 (one), wherein A is a diameter of the connection hole and B is a film thickness (about 1 .mu.m) of the interlayer insulating film, particles 203 of the oxide and the fluoride of aluminum sputtered by the argon ion 202 sufficiently scatter up to the outside of the connection hole 6, as shown in FIG. 8A. Therefore, the deterioration layer 201 of the aluminum is removed and thus the surface of the first aluminum interconnection layer 4 in the connection hole 6 can be cleaned.
However, if the connection hole 6 having the diameter at the sub-micron level and the aspect ratio (B/A) over one, as shown in FIG. 8B, the particles 203 of the oxide and fluoride of aluminum sputtered by the argon ion 202 is partially blocked by the side wall of the connection hole 6, and thus can not scatter to the outside of the connection hole 6. Therefore, some of the particles 204 re-stick onto the inside of the connection hole 6. This phenomenon is reported in "A New Reliability Problem Associated with Ar Ion Sputter Cleaning of Interconnect Vias", H. Tomioka et al, IEEE/IRPS, 1989, pp. 53-58.
As a result, even if the continuous deposition of the second aluminum interconnection layer 7 in a vacuum is carried out as a next step, the particles 204 of the oxide and fluoride of aluminum, which have stuck onto an interface 205 between the first and second aluminum interconnection layers 4 and 7 in the connection hole 6 during the sputter etching, remain there. Thereby, in the heat treatment at about 400.degree.-450.degree. C. after the formation of the second aluminum interconnection layer, mixing can not be sufficiently effected at the interface 205 between the first and second aluminum interconnection layers.
Consequently, a contact resistance (called a "via-hole resistance") in the connection hole 6 may be increased and/or an open failure, i.e., a failure in conduction between the first and second aluminum interconnection layers, may be caused.
Further, even if the initial via-hole resistance has a correct value owing to a heat treatment at 400.degree.-450.degree. C. described above, the mixing has not been sufficiently effected at the interface 205 between the first and second aluminum interconnection layers. Therefore, the reliability in the connection hole 6 such as resistance against the electro-migration and stress-migration is reduced.
These problems are and will be significant in the semiconductor integrated circuit devices which are miniaturized in the half micron order and the semiconductor integrated circuit devices which, in the future, will be miniaturized in the sub-micron order and thus will have a further increased aspect ratio (B/A).
Aspect ratio (B/A), considerations also apply to contact holes for lower wiring layers other than the aluminum and the silicon semiconductor substrate, e.g., to the contact hole 308 shown in FIG. 7B. However, a natural oxide film, deterioration layer and/or others which are formed on the surface of the contact hole 308 can be selectively removed by the cleaning processing with adequate acid or alkali such as hydrofluoric acid.
However, in the via-hole part described above, the lower wiring layer is formed of the aluminum interconnection layer having less resistance against solution of the acid and alkali. Therefore, it is impossible to employ the above described cleaning processing with the strong acid or alkaline for removing the deterioration layer and others.
The Japanese Patent Laying-Open No. 64-59937 (1989) has disclosed a Ti film which is formed at a thickness of 1000 .ANG. as a base film of the second aluminum interconnection layer. However, this Ti film easily reacts with the second aluminum interconnection layer located above it in the heat treatment after the formation of the interconnection layers, and does not sufficiently react with the lower layer, i.e., the first aluminum interconnection layer, in the connection hole. Therefore, this Ti film does not serve to promote the mixing at the interface between the first and second aluminum interconnection layers.
The Japanese Patent Laying-Open No. 61-90445 (1986) "Multilevel Interconnection for Half-Micron VLSI's", T. Nishida et al, VMIC Conference, 1989, pp. 19-25, have disclosed TiN film formed as a base film of the second aluminum interconnection layer. However, this TiN film lacks a reactivity with the aluminum interconnection layer. Therefore, this TiN film does not serve to promote the mixing at the interface between the first and second aluminum interconnection layers.

Interconnection structure of semiconductor integrated circuit device


A method is provided to suppress detachment between semiconductor packages while preventing dislocation at the time of mounting a stacked semiconductor package on a motherboard. Semiconductor packages PK1 and PK2 are bonded to each other through protruding electrodes and resin is provided between the semiconductor packages PK1 and PK2. The resin is provided in the peripheries of the protruding electrodes so as to contact each of the protruding electrodes while not contacting a semiconductor chip.

1. Field of the Invention
The present invention relates to a semiconductor device, an electronic device, an electronic apparatus, and a method of manufacturing a semiconductor device, and particularly to those suitable for being applied to a stacked structure of a semiconductor package.
2. Description of the Related Art
As for the conventional semiconductor package, there has been attempting to save space by stacking semiconductor packages through solder balls, for example, as disclosed in Japanese laid-open patent publication No. 6-13541. In order to prevent displacement caused by solder balls between the semiconductor packages being re-melted at the time of mounting a stacked semiconductor package on a motherboard, resin is filled between stacked semiconductor packages.
However, as for a conventional semiconductor package, resin is filled in the whole gap between semiconductor packages that are stacked through solder balls. For this reason, when curing the resin that is filled between semiconductor packages, moisture contained in the resin does not fully drain out, and thus the moisture remains in the resin that is filled between the semiconductor packages. Therefore, when executing re-reflow at the time of mounting a stacked semiconductor package on a motherboard, there has been a problem in that moisture contained in the resin, which is filled between the semiconductor packages, evaporates to expand, thereby causing detachment between the semiconductor packages.
The present invention is intended to provide a semiconductor device, an electronic device, an electronic apparatus, and a method of manufacturing a semiconductor device, which can prevent detachment between semiconductor packages while preventing displacement at the time of mounting a stacked semiconductor package on the motherboard.

Semiconductor device, electronic device, electronic apparatus, and method of manufacturing semiconductor device


Techniques are disclosed for providing a multidirectional swipe key for a virtual keyboard of a touch sensitive computing device. The multidirectional swipe key can be used to translate one or more swipe gestures started from the key into cursor movement (or directional input). The characteristics of the multidirectional swipe key gestures, such as the swipe direction and/or swipe length, may affect the resulting cursor movement (or directional input). The multidirectional swipe key may be configured such that held swipe gestures cause continual cursor movement (or directional input). The multidirectional swipe key may also be configured such that dragging the gesture to make a longer swipe accelerates cursor movement (or directional input) and vice versa.

Touch sensitive computing devices such as tablets, eReaders, mobile phones, smart phones, personal digital assistants (PDAs), and other such devices are commonly used for displaying consumable content. The content may be, for example, an eBook, an online article or website, images, documents, a movie or video, or a map, just to name a few types. Such devices are also useful for displaying a user interface that allows a user to interact with one or more applications or services running on the device. In some instances, the content is displayed and interacted with using a touch screen, while in other instances, the touch sensitive surface (such as a track pad) and display device (such as a non-touch sensitive monitor) may be separate. The user interface for these touch sensitive computing devices typically include a virtual keyboard (also referred to as a soft keyboard) for entering text and other characters. The virtual keyboard is typically displayed when a user is interacting with a text entry box or other various text input fields.

Multidirectional swipe key for virtual keyboard


Computer program product for supporting a user in designing a sealing system of a hydraulic cylinder by indicating at least one sealing system component related to one of: seals, guide rings and rod end bearings for application in the hydraulic cylinder based on the working conditions of the hydraulic cylinder. The computer program product is arranged to obtain sealing system component information items from a database, including: a sealing system component text information item; a duty level information item; a sealing system component graphic information item; and a rod end information item. The rod end information item includes sealing intensity as a function of environment temperature.

The progress in the fields of computers and communications have reached a point where they can offer an increased competitive advantage for companies also within more mature technical fields, such as bearings and seals.
The knowledge contents of products and procedures related to these products have increased during the last decade. Even though the basic principles of today's bearings and seals in some cases are almost 100 years old, the knowledge involved with today's bearings, rings and seals has increased in importance.
As a result of the growing knowledge in the field of bearings and seals during recent years, products, their use and application have become more differentiated and complex. Also the knowledge of designing technical solutions incorporating bearings and/or seals in other products has become increasingly important during recent years. An example of knowledge related to a technical solution is knowing what specific sealing system to use in a specific application and what bearings not to use. Using non-optimum sealing systems increases the likelihood of malfunction or at least a shortened machine life.
Superior manufacturers of bearings and seals have noticed the quality of offering supporting knowledge to customers, potential customers, and technical staff. The increased knowledge contents in this field have lead to an increased need of conveying information that a customer can use as support. For instance the risk of a customer selecting a non-optimum product component or application of a product has increased due to the increased knowledge contents that has to be associated with the modern products today in the bearings and seals industry. Today additional support is in some cases necessary. Otherwise the customer is at risk of a lower performance of an application of a sealing system.
More specifically, off road machinery in mining and construction requires today 10,000 hours, or more, of maintenance-free operating time for the hydraulic cylinders that are used. Offering this amount of maintenance-free operating time is difficult to reach for suppliers of hydraulic cylinders and their components included. Therefore, the hydraulic cylinders are one of the most critical parts of such mobile equipment and the seals and the bearings are the weakest components in a hydraulic cylinder.
About 75% of all complaints concern leakage, mainly caused by damaged seals and sometimes also by bad welding. The lifetime for a bearing is usually strongly decreased by the encroachment of contaminants into the bearing with damage and high down time costs as a result.
Recent knowledge indicates that it is not the choice of the design of the individual seal, wiper, guide ring or bearing which provides the maintenance-free applications, maintenance-free operating times exceeding 10,000 hours, but it is the distinct balance in function between rod/piston sealing and guiding elements, as well as the right choice of rod end/bearings that increase the number of maintenance-free hours. This implies a holistic view of the design process of the sealing system of a hydraulic system instead of an analytical view construing the design process as a number, or sequence, of sub problems.
Thus, today when a sealing system of hydraulic cylinders is designed, a holistic view is normally not used. This may result in poor choices by the designer of the design of the combination of seals, wiper, guide rings and bearings if the distinct balance in function between rod/piston sealing and guiding elements, as well as the right choice of rod end/bearings, will not be achieved.
An indistinct balance may lead to a number of disadvantages of the hydraulic cylinder:                1) Limited maintenance-free operating lifetime of the hydraulic cylinder.        2) Decreased security of the sealing system of the hydraulic cylinder, since a poorly designed sealing system of a hydraulic system may lead to a collapse of the hydraulic cylinder.        3) Limited duty ability of the hydraulic cylinder.
A drawback of the design process today is that the information that is necessary can primarily be found only in printed material, such as manuals and product catalogues. This may make searching for information of for instance a specific seal, tedious. There is also an uncertainty aspect since there is a risk of mistakes when looking in printed material and transferring the information into the design. This may lead to wrong data being included in the design. For instance there is a risk that a seal which is not suited for a specific kind of duty will be wrongly included in the design by the designer.
Another drawback of the design process of sealing systems involves the limited possibilities of grasping the big picture of the design process. The big picture is considered important especially in the early phase of the design process.
Yet another drawback of the design process involves the limited possibilities of interacting with the production/mounting process. Today, it is not always easy for production/mounting personnel to obtain clear instructions from drawings provided by the designer.

Computer program product and a carrier for supporting a user designing a hydraulic cylinder by indicating preferred components of seals, rings and bearings


A heating apparatus is configured to include a hot plate at which a substrate is placed, a top plate opposed to the substrate, a gas discharging part provided on one end side of the hot plate for discharging gas between the hot plate and the top plate, an exhaust part provided to be opposed to the gas discharging part with the hot plate interposed therebetween, and a heating part independently heating a first region and a second region of the substrate. A heating process is performed with good within-wafer uniformity by forming an unidirectional flow to heat the first region and the second region at different temperatures.

1. Field of the Invention
The present invention relates to a heating apparatus performing a heating process on a substrate coated with a coating liquid, a coating and development apparatus including the heating apparatus, and a heating method.
2. Description of the Background Art
An apparatus for forming a resist pattern on a glass plate for a semiconductor wafer (referred to as a wafer hereinafter) and an LCD (Liquid Crystal Display) includes a coating and development apparatus applying a resist on a wafer and developing the exposed wafer. This apparatus is equipped with a heating apparatus called a baking apparatus or the like. An apparatus that heats a wafer coated with a resist liquid, for example, serves to dry a solvent in the resist liquid.
Such a heating apparatus generally includes a hot plate 11, over which a cover body 12 lies, as shown in FIG. 13. While gas is supplied to the inside of cover body 12 from a gas supply port 13 formed around the entire circumference of a wafer W1, the gas is sucked and exhausted from the central portion of the cover body 12. In this manner, a heating process is performed while a gas flow from the outer circumference of the wafer toward the center is formed, as represented by the arrow in the figure. However, when a gas flow is formed in this manner, sublimation substances subliming from the resist liquid is likely to attach to the wafer as particles even with a uniform temperature within the surface of hot plate 11, for which reason is not clarified, though.
On the other hand, Japanese Patent Laying-Open No. 2004-293924 discloses a heating apparatus performing dry processing on a glass substrate for LCD coated with a polyimide solution for an alignment film, in which a passage of a gas flow is formed by placing a cover over a region above a hot plate. A heating process is performed while a gas flow from an opening on one side of the passage toward the other side is formed. The inventor understands that the amount of the attached sublimation substances on the wafer is reduced when the technique of forming a gas flow from one end side to the other end side, so to speak, a unidirectional flow is applied to the wafer heating apparatus, as compared with when a gas flow is formed from the outer circumference to the center of the wafer. In this case, however, the velocity of flow is high at the other end side of a wafer from which a gas flow is exhausted. Therefore, the heating process may not be uniform, so that the resist film may lack uniformity.
In addition, such a heating apparatus has also the following problem. The particles on the heating plate is transferred to the wafer when the wafer is brought into surface contact with the heating plate. Thus, a plurality of protrusion portions each having a height of 0.1 mm are usually provided on the heating plate, so that the wafer placed thereon is slightly isolated from the heating surface (Japanese Patent Laying-Open No. 2001-274052). This height is set at a minimum value such that the wafer does not contact with the heating surface. With a larger value, it is difficult to keep the wafer-heating temperature uniform.
Now, with the increased wafer size in diameter, a semiconductor manufacturing apparatus for a 12-inch wafer (a diameter of 30 mm) is put into practice, and a wafer with a even larger diameter has been developed. However, with the 12-inch or larger size, some wafers may badly warp. Accordingly, with a height of 0.1 mm of a protrusion provided on the heating plate, the wafer may come into contact with the hot plate and become misaligned. Moreover, when the wafer is delivered onto the hot plate (the protrusion portion), the wafer may slide sideways as if it is placed on an ice face. This phenomena takes place since an air layer is presumably formed in such a manner that the air is enclosed and slightly pressurized in a small space under a large-diameter wafer.

Heating apparatus, coating and development apparatus, and heating method