A method is disclosed for accurately detecting an outflow of a slag into a stream of a molten steel when the molten steel is poured from a first vessel such as a refining furnace or a ladle into an intermediate vessel such as a ladle or a tundish through a melt-discharging hole or a nozzle. At that time, an inert gas is fed into the stream of the molten steel in the nozzle through a side portion of the melt-discharging hole or the nozzle, and the detection is made based on a change in a flow rate of the inert gas sucked into the stream of the molten steel and/or in a back pressure.

Slag is ordinarily likely to flow out into a stream of a molten steel in a final stage of discharging the molten steel from a refining furnace such as a converter to a ladle through a molten steel-discharging opening, or in a final stage of pouring the molten steel from a ladle to an intermediate vessel such as a tundish through a nozzle.
If the slag is discharged into the molten steel, alloying components such as Al, Fe-Mn and Fe-Si added thereto are taken into the slag, and production cost rises due to reduction in yields of such alloying components. Further, since the molten steel is oxidized with the slag discharged, cleanness of the steel is deteriorated, so that the quality of steel products is adversely affected. For this reason, it is an extremely important control item to suppress the outflow of the slag into the molten steel to the minimum, and various countermeasures have formerly been adapted for this purpose.
As the conventional techniques for detecting the outflow of the slag into the molten steel stream, visually judging is a main technique. As methods for detecting the slag entering the stream extracted, particularly, from the ladle to the tundish, for instance, Japanese Patent Application Laid-open No. 57-112,963 discloses a process for measuring vibrations, Japanese Patent Application Laid-open No. 53-53,521 discloses a process for measuring the impedance, Japanese Patent Application Laid-open Nos. 60-3,955 and 60-3,956 disclose a process for measuring microwaves, and Japanese Patent Application Laid open No. 61-262,454 discloses a process for measuring the internal pressure of a nozzle.
However, the above-mentioned conventional techniques have the following problems.
That is, the above visual judgment lacks accuracy, because variations occur due to individual differences among judging persons. The judgment needs longer time, and it is impossible to make any such judgment in the case where a poured molten steel as in a sealed type tundish is not observable from the outside.
The vibration-measuring process, the impedance-measuring process, and the microwave-measuring process require that a measuring sensor is caused to approach the extracted stream. Thus, problems exist with respect to maintenance or operability. Furthermore, the apparatus disadvantageously becomes great size, and costly.
In the nozzle internal pressure-measuring process, a pressure-measuring hole is liable to be closed with the molten steel or the slag on measuring a negative pressure inside a long nozzle. Thus, the pressure cannot be detected in many cases. Moreover, since the change of pressure inside the nozzle is as extremely small as about 0.02 kgf/cm.sup.2 when the poured melt stream is changed from the molten steel to the slag, it is difficult to accurately detect the change. In addition, since the pressure loss is great depending upon the shape of the pressure-measuring hole, it may become impossible to detect the pressure change due to the slag discharging. Thus, the pressure cannot accurately be detected. Furthermore, the internal pressure of the nozzle detected by this method is measured by press fitting a long nozzle to a nozzle of the ladle, purging the inside of the nozzle through blowing an inert gas upon a press-fitted portion via an inert gas-blowing pipe, and measuring the static pressure (negative pressure) inside the nozzle. Although the inclusion amount of the inert gas into the molten steel stream differs from the inclusion amount of the inert gas owing to the discharging slag (the amount of the gas sucked through the press-fitted portion), the inert gas is sucked through the press-fitted portion so that the internal pressure may be constant irrespective of the flow-down kinetic energy of the flowing material. Therefore, since the internal pressure inside the nozzle is maintained at almost the same level, this process has a shortcoming in that the discharging of the slag cannot stably or accurately be detected.


A square RSC carton for potted plants and flowers to be used for shipping the potted item in the carton to the retail store, and for display of the potted item at the retail store. The top flaps are perforated for removal of arcuate portions of the top flaps and form a circular rim defining an aperture through which the flower pot is placed for support of its flange on the top flaps at the circular rim. "Pop-in" segments are formed across the corners of the adjacent side panels by parallel lateral slits and parallel vertical hinges enabling reversing the structure to support the weight of the flower pot by the top flaps. The top flaps are also infolded at second fold lines to suspend the flower pot below the top end of the carton thereby hiding the pot inside the display and showing only the flowers or plant.

There exists a need to not only package plants and flowers that are in pots to ship them to the marketplace, but also to attractively display the product at the retail environment.
Typically, potted plants are handled either in bulk form or are placed in a shipping carton and transported or shipped to market. The shipping carton needs to retain the pot or potted plant in a position within the carton, and for such purpose, various cartons are devised with partitions or holding elements adhesively secured or stapled into the sides or panels of the box, which are folded to a position to restrain and retain the flower pot. A typical example of such a carton is disclosed in U.S. Pat. No. 1,469,536 and in U.S. Pat. No. 3,342,329. Other containers exist for shipment of perishable cut flowers and plants that may be used for displaying same for sale at their destination. Examples of such a container are disclosed in U.S. Pat. Nos. 3,754,642 and 4,113,093.

Fresh potted plant shipping and display carton


A leach resistant composition includes a quaternary ammonium complex of heparin and a silicone. A method for applying a coating of the composition to a surface of a medical article is within the purview of the present invention. Medical articles having surfaces which are both lubricious and antithrombogenic, are produced in accordance with the method hereof.

1. Field of the Invention
This invention relates to medical articles, and more particularly relates to a lubricious and antithrombogenic composition and method for its application to a medical article.
2. Background of the Invention
Extensive investigations have been undertaken over many years to find material that will be biologically and chemically stable toward body fluids. This area of research has become increasingly important with the development of various objects and articles which may come into contact with blood, such as artificial organs, vascular grafts, probes, cannulas, catheters and the like.
Synthetic plastics have come to the fore as preferred materials for such articles. However, such materials have the major drawback of being thrombogenic. Even such plastics as polytetrafluoroetheylene and the silicone rubbers, which are more compatible with blood than most plastics, still show thrombogenic characteristics.
Often, use of such articles, as for example, probes, cannulas, catheters and the like, include puncture and passage of the article through the skin. Friction between the patient's skin and the plastic surface of the article may cause substantial discomfort to the patient. Further, catheters are often used in conjunction with an introducer device which typically contains a soft rubber one-way check valve through which the catheter must be threaded. When one surface of an article must slide across another surface, friction may develop which can cause damage to the article. In particular, fragile catheter balloons may be damaged by friction during passage through the valve of the introducer. Thus, both antithrombogenicity and lubricity are highly desirable properties for article surfaces to come into contact with blood.
Surfaces may be rendered lubricious by simple application of any common lubricant. Silicone oils are generally recognized to be among the best lubricants available. Application of a silicone lubricant to a surface is known to result in significant reduction in the surface drag upon catheter insertion, facilitate catheter placement, and reduce the force required for catheter retraction. However, a silicone lubricant coated over a heparinized surface in accordance with the prior art masks the heparin and severely compromises its antithrombogenic activity.
Thrombogenicity has conventionally been counteracted by the use of anticoagulants such as heparin. A variety of heparinization procedures have been reported. For example, Solomon et al., in U.S. Pat. No. 4,521,564, discloses a method to convalently bond heparin to a polyurethane substrate. Eriksson et al., in U.S. Pat. No. 4,118,485, coats a plastic surface with a complex of heparin and either an alkylamine salt or a quaternary amine salt and subsequently stabilizes the heparin by crosslinking with a dialdehyde.
Williams et al., in U.S. Pat. No. 4,613,517, reveals a process for ionically bonding heparin to a polymeric surface including the steps of plasma-treating the surface, absorbing a surface active agent onto the plasma-treated surface, reacting the surface active agent with heparin, and crosslinking the heparin with glutaraldehyde.
Substrates rendered blood compatible by coating with a layer of silicone have been disclosed. Durst et al. in Am. J. of Roent., Radium Ther. and Nuclear Med., 120, 904 (1974) reported that, in vitro, siliconized stainless steel guidewires, polytetrafluoroethylene coated guidewires and polyethylene catheters were hypothrombogenic compared to untreated substrates, but, in vivo in dogs, no antithrombogenic effect was observed except with heparin coated substrates.
McGary et al., in U.S. Pat. No. 4,678,660, discloses dipping a polyurethane substrate into a solution of a complex of heparin and tridodecylmethyl ammonium chloride (TDMAC) in polyurethane to form a layer of the complex in polyurethane on the substrate. A lower leach rate of heparin is claimed for the patented product having heparin distributed throughout the polyurethane layer as compared to heparin ionically bonded to TDMAC on the surface of the polyurethane substrate.
U.S. Pat. No. 4,529,614 to Burns discloses coatings of an anticoagulant and a water soluble copolymeric silicone applied to plastic surfaces. The coatings render the surfaces hydrophobic and dissolve in the blood to impart anticoagulant properties to a sample to be analyzed.
Thus, while the prior art has recognized for many years the desirability of rendering substrate surfaces antithrombogenic or lubricious, there are no reports known to the authors of the simultaneous achievement of both effects. The present invention addresses this need.

Blood compatible, lubricious article and composition and method therefor


Structures and assemblies for stowable tables and similar objects are detailed. Versions of the assemblies may cooperate with pivoting covers mounted to vehicle seats for purposes of deploying and retaining the tables. Other versions may include tables biased to fit snugly in recessed portions of backrests of seats, with compression of the biasing mechanism occurring sometimes when backrests are reclined and expansion of the mechanism occurring sometimes when the tables are deployed. Yet other versions may include tables latching to bars or other objects protruding rearward from the backrests.

This invention relates to stowable tables and associated storage assemblies and more particularly (although not exclusively) to tray tables used for food service and other functions aboard vehicles such as (although again not exclusively) passenger aircraft and trains.
Commonly-owned U.S. Pat. No. 4,944,552 to Harris discloses stowable table systems for commercial vehicles including aircraft. Designed for stowage in a compartment within an armrest of a seat, the table of the Harris patent is adapted xe2x80x9cto be angularly displaced to a degree sufficient to permit the user to leave the seat obstructed by the tablexe2x80x9d when the table is xe2x80x9cin its horizontally disposed position of use.xe2x80x9d See Harris, col. 1, ll. 10-13. Because storage of the table occurs within the armrest of a seat, no latching mechanism is necessary to retain the table in its stowed position.
Recently-issued U.S. Pat. No. 6,237,994 to Bentley, et al., also commonly-owned with this application, describes multi-function seats for aircraft and other vehicles. Discussed in the Bentley, et al. patent are table assemblies again often (although not necessarily) stowed in compartments within armrests of seats. Among features of these assemblies are that the upper surfaces of the tables may function as non-horizontal rests for, e.g., books, magazines, or computers and the tables themselves may be adjustable vertically for passenger comfort.
Illustrated in the Bentley Application are tables that may be latched, or otherwise connected, to rear portions of backrests of seats. As described in the Bentley Application, pins present in a table may engage slot-containing members connected directly or indirectly to a backrest to retain the table in an undeployed condition (as is frequently required at least during taxi, take-off, and landing of commercial aircraft). In some embodiments of the invention, by rotating a knob or similar structure, a passenger may retract the pins from the slots to deploy the table for use.
Unlike most existing commercial vehicle chairs, seats detailed in the Bentley Application are adapted for both rotational and linear movement. Accordingly, the slots mentioned in the preceding paragraph may be elongated with respect to the pins, thus permitting the backrest to move substantially before mandating any corresponding movement of the (undeployed) table. Such substantial movement may occur, for example, when the backrest reclines upon passenger demand.
The present invention provides alternative structures and assemblies for stowable tables and similar objects. Typically connected directly or indirectly to backrests of seats, tables of the invention may be latched, or otherwise retained in stowed positions, in numerous ways. In some embodiments, tables may cooperate with pivoting covers for retention and deployment purposes. In other embodiments, tables may be biased to fit snugly in a recessed portion of a backrest when stowed, with the biasing mechanism also permitting extension of the table toward a passenger when the table is deployed. In yet other embodiments, both of these features may be utilized (or combined with any of the structure of the Bentley Application) if appropriate or desired. Similarly, any of these embodiments may include conventional or other latching mechanisms for added retention assurance. Further embodiments, alternatively or additionally, may permit tables to latch to bars or other objects protruding rearward from backrests of seats.
Versions of the innovative assemblies incorporating covers typically include a cover attached to a portion of the rear or sides of a backrest. The cover defines a space between its surface and the rear of the backrest into which a portion of a tray table may be stowed. Assuming the cover is sufficiently rigid as not to deform when contacted by the table, its presence can help prevent undesired deployment of the table. Likewise, if used with the seats and tables of the Bentley Application, the cover effectively can shield passengers from any gap that might be present between an undeployed table and the rear of the backrest of a reclinable seat. Preferably the cover is mounted to the backrest so as to be able to pivot about the mounting to facilitate deployment and stowage of the associated table.
Biasable versions of the assemblies may include one or more springs cooperating with the mechanism used to extend and retract the table respectively toward and away from a passenger. In their uncompressed state, the springs may extend the table toward the passenger when deployed. To return a table to its stowed position within a recess in the seatback, the passenger need merely push the table so as to compress the spring and fit the table within the recess. Because once the table is so fitted the spring will attempt to return to its uncompressed state, it can cause the distal end of the table to fit snugly against the corresponding end of the recess, thereby assisting retention of the table.
It thus is an object of the present invention to provide structures and assemblies for stowable tables and similar objects.
It is also an object of the present invention to provide mechanisms for retaining tables in stowed positions.
It is another object of the present invention to provide assemblies in which a stowable table cooperates with a cover connected directly or indirectly to the backrest of a seat.
It is a further object of the present invention to provide assemblies in which the cover is adapted to pivot to facilitate deployment and stowage of an associated table.
It is an additional object of the present invention to provide assemblies in which a table is biased to fit snugly in a recessed portion of a backrest when stowed.
It is too an object of the present invention to provide assemblies in which tables latch to bars or other objects or members protruding rearward of backrests of seats.
It is yet another object of the present invention to provide assemblies in which a table-biasing mechanism may be used to extend a deployed table toward an associated passenger.
Other objects, features, and advantages of the present invention will be apparent to those skilled in the art with reference to the remainder of the text and drawings of this application.


A swimming pool safety cover of the solid fabric variety includes a flexible cover fabric formed of a plurality of reinforced thermoplastic polymer pieces assembled and heat sealed along their edges to form a unitary cover conforming to the shape of the pool and a plurality of anchor straps, each strap extending along a portion of and heat sealed to one side of the cover and projecting outwardly from, and spaced apart along, the periphery of the cover. The projecting portion of each anchor strap is sufficiently long to attach to the hardware and the portion of each strap extending along and heat sealed to the cover is no longer than one to three times the length of the projecting portion.

Drowning is one of the leading causes of death for children age 14 and under and 75 percent of children involved in swimming pool accidents are between 1 and 3 years old. One of the most important safety devices for any swimming pool is a pool safety cover to prevent harm to small children and animals venturing into a swimming pool area by inhibiting their access to the water in the pool. Standard performance specifications for pool safety covers are set forth in ASTM F 1346-91 and are intended to reduce the risk of drowning by a child under five years of age. In this regard, pool safety covers are very different from pool liners which merely line the floor and/or walls of the interior of the pool and pool covers whose primary purpose is to prevent debris from entering the pool and not to provide a high level of safety for children under the age of five by inhibiting their access to the water.
Pool safety covers must meet rigorous strength and safety specifications. Thus, for pools having diameters greater than eight feet, the safety cover must be able to support the weight of two adults and a child, i.e., at least 485 pounds. In addition, the safety cover must be designed in such a way that if a child under the age of five were to fall onto the cover neither that child nor another child could slip through any openings that may occur between the safety cover and the side of the pool or gain access to the water. Still further, safety covers must either incorporate a drainage system or have an auxiliary system provided which will drain substantially all standing water from the cover within thirty minutes after cessation of normal rainfall. This is to prevent the formation of water puddles on the upper surface of the pool cover since these puddles can constitute a drowning hazard for small children under five years of age. Finally, a safety cover must be so constructed that any opening in the cover or between the cover edge and the deck surface or coping wall and the top surface of the pool is sufficiently small and strong to prevent the opening from being forced to a size that a small child's head could gain access to the water.
Historically, solid pool covers were made using light gauge polyvinyl chloride (PVC) and were held in place around the pool with weights, most typically water filled bags. These covers, while protecting the pool from debris entering the water during the non-swimming season, sagged, stretched, collected water and became a drowning hazard. Light weight mesh covers were developed to allow water to pass through to avoid puddling while maintaining most of the debris on top and out of the pool water. However, as debris collected on top of the mesh cover, it pressed the cover material into the water and contributed to the accumulation of dirt in the pool. Over time better materials became available but none of these early pool covers could truly be considered "safety" covers until reinforced vinyl and the use of tension straps came into use. There are currently two varieties of safety pool covers, mesh and solid. Both types are anchored to a pool decking with straps that are attached to the cover and which are used to pull the cover taut over the pool. The straps are usually attached to stainless steel compression springs and are coupled to recessed anchors embedded in the deck surface. When the cover is removed, deck anchors which are not already flush with the deck can be screwed down to prevent tripping or toe-stubbing. Mesh covers allow rain and snow to drain through the mesh, avoiding puddling; however, dirt and silt can pass through the webbing and dirty the pool water. Solid pool covers keep the pool free of dirt and silt; however, they are subject to puddling on the surface, necessitating the use of drain panels in the solid cover or small cover pumps to automatically pump accumulated water off the cover.
Referring to FIG. 1, conventional prior art safety pool covers are formed of either a strong mesh fabric or a solid non-porous fabric reinforced by attached webbing strips or straps which extend across the entire length and width of the cover in typically perpendicular crossing patterns across one or both sides of the fabric and extend outwardly from the perimeter of the cover. The cover is held taut over the water surface of a swimming pool by compression springs coupling the outwardly extending straps to anchors embedded in the deck surface surrounding the pool. These covers are normally suspended above the entire water surface and extend beyond the edge of the pool about 12 to 18 inches onto the surrounding deck surface so that, in compliance with ASTM F 1346-91, there are no openings providing access to the water through which children or animals can fall or become lodged. Likewise, in compliance with ASTM F 1346-91, the covers are designed to support the weight of two adults and a child without structural failure. Safety covers are preferably custom made for pools to assure proper fit, although ready made safety covers are often used for pools having conventional shapes and sizes, such as rectangular pools. Prior art safety covers are typically manufactured from sheets of mesh or solid fabric which are cut into appropriately sized pieces for a particular pool, e.g., 3′×3′ or 5′×5′ squares, and then stitched to the typically crisscrossed webbing straps to form a pool cover having the desired shape for covering the particular swimming pool. In all prior art pool safety covers the seams between pieces of fabric and the webbing straps are stitched using thread. It has been found, however, that stitching carries a high risk of failure especially over time as water, chemicals and weather conditions cause the webbing straps and stitching to dry rot or otherwise deteriorate and, ultimately, fail. Accordingly, there is a need for a pool safety cover which meets the specifications of ASTM F 1346-9, which is not subject to deterioration and failure due to water, chemical exposure and/or weather conditions and which does not exhibit the other disadvantages of conventional prior art pool safety covers.


A static content addressable memory (CAM) cell. The CAM cell includes a latch having complementary data nodes capacitively coupled to ground, first and second access transistors, each coupled between a data node of the latch and a respective data line. The gates of each access transistor is coupled to a word line such that when activated, the respective data node and data line are coupled. The CAM cell further includes a match circuit coupled to one of the complementary data nodes of the latch. The match circuit discharges a match line in response to a data value stored at the data node to which the match circuit is coupled and compare data present on the respective data line mismatching. Two of the CAM cells can be used to implement a full ternary CAM cell.

The present invention is related generally to the field of semiconductor memory devices, and more particularly, to static content addressable memory cells and methods for storing data therein.
Content addressable memories (CAMs) are used in a variety of applications requiring pattern matching operation on bits, such as virtual memory, data compression, caching, and table lookup applications. With the popularity of high speed networks, wired or wireless, on the rise, CAMs have been frequently employed in networking equipment, particularly routers and switches, computer systems and other systems that require content searching, such as in network-address filtering and translation by matching partial node address. For example, in network router or switch, CAM devices are used to store Internet Protocol (IP) addresses and routing instructions associated with each address. When an IP packet is received and the IP address obtained, the router must retrieve the routing information for the packet in order to send it on the most direct route to the desired IP address. By using a CAM memory device, the router can search the CAM for the desired IP address. That is, the CAM searches for the desired content, and if there is a match, the CAM returns the associated routing information.
CAM devices can store data much like conventional memory devices. Generally, an address is provided by a controller to the CAM device, the address is used to access a particular memory location within the CAM memory array, and then the content stored in the addressed memory location is retrieved from the memory array. However, as previously discussed, CAM devices provide the added functionality of being able to search the stored data for desired content. That is, in addition to simply storing data in its memory array, a CAM device can search the memory array based on compare data corresponding to the desired content. When the content stored in the CAM memory array does not match the compare data, the CAM device returns a no match indication. However, when the content stored in the CAM memory array matches the compare data, the CAM device outputs information associated with the content.
CAM storage cells have been implemented using dynamic random access memory (DRAM) cells, as well as static random access memory (SRAM) cells. One of the benefits of using a DRAM cell structure for CAM cells is that they are smaller in size relative to SRAM cells. However, as with conventional DRAM cells, such designed CAM cells need to be periodically refreshed in order to maintain the integrity of the data, as is well known. CAM devices designed with DRAM cells also require that the rows of the CAM device to be read sequentially, one row at a time, which is prohibitively slow. Moreover, due to the match circuit that is included with CAM cells, there are more leakage paths from the storage node. The techniques used in DRAM cells to reduce transfer gate leakage may not be readily available to CAM cell designs.
As previously mentioned, CAM cells have also been implemented using SRAM cell designs. Although larger in size than DRAM cells, SRAM cells provide the benefit of not needing to be refreshed to maintain data integrity. SRAM cells have been designed with six transistors (6T) as well as four transistors (4T). The 6T SRAM cells provide the benefit of having relatively low soft-error rates. xe2x80x9cSoft-errors,xe2x80x9d as known in the art, are those errors that are typically caused by power supply problems or alpha particles. Although 4T SRAM cells are smaller relative to their 6T counterparts, the 4T SRAM cells have higher soft-error rates. This issue is particularly significant with respect to CAM devices, since the data stored in the CAM memory array essentially represents a database of information. That is, the soft-error rate of conventional 4T SRAM cells may be unacceptable in the application of a CAM device. Consequently, choosing to design a CAM device using a 6T SRAM structure, which, as previously mentioned, are relatively larger, may be an acceptable compromise in light of the more significant issues that arise where the integrity of the data in the CAM cell is questionable.
Accordingly, there is a desire and need for an alternative CAM cell design that is relatively small and yet has acceptably low soft-error rates.
The present invention is directed to a static content addressable memory (CAM) cell. The CAM cell includes a latch having complementary data nodes capacitively coupled to ground, first and second access transistors, each coupled between a data node of the latch and a respective data line. The gates of each access transistor is coupled to a word line such that when activated, the respective data node and data line are coupled. The CAM cell further includes a match circuit coupled to one of the complementary data nodes of the latch. The match circuit discharges a match line in response to a data value stored at the data node to which the match circuit is coupled and compare data present on the respective data line mismatching. Two of the CAM cells can be used to implement a full ternary CAM cell. In storing data in the CAM cell, a first one of the data nodes is charged and the other data node is coupled to ground. The capacitive coupling of the first data node assists in is maintained the charge state.


Provided are: a first entry preventing nail that interferes with a cartridge at a position closer to an insertion/extraction port than an insertion completed position of an insertion-side end face of the cartridge inserted first; a second entry preventing nail at a position with a space from the first entry preventing nail slightly longer than length of the cartridge, which allows entry of the cartridge and retreat of the first entry preventing nail at that position when a tapered face of the cartridge is at that position while preventing the entry of the cartridge and retreat of the first entry preventing nail at that position when the tapered face of the cartridge is not at that position; and a linkage module which allows advancing and retreating actions of the first and second entry preventing nails in a tradeoff relation.

1. Field of the Invention
The present invention relates to a cell of a magnetic tape library device which includes a housing space for housing a plurality of magnetic tape cartridges in series by aligning the directions thereof and an insertion/extraction port for inserting and extracting the plurality of magnetic tape cartridges, and to a cartridge misinsertion preventing mechanism thereof.
2. Description of the Related Art
As a technique related to preventing misinsertion of the magnetic tape cartridges, a library device disclosed in Japanese Unexamined Patent Publication 2010-86578 (paragraphs 0005, 0021, FIG. 6A, FIG. 6B, FIG. 6C) (Patent Document 1), for example, is known.
This is a technique with which a medium position detecting mechanism constituted with a color filter, an arm rotating mechanism, and the like is provided to each housing position of each magnetic tape cartridge, and misplacement of the magnetic tape cartridges is detected by an optical detecting module constituted with a light source and a mirror. However, the structure thereof is complicated, so that the manufacturing cost of the magnetic tape library device is increased substantially.
Further, this device has only a function of detecting the misplacement of the magnetic tape cartridges but has no function of preventing misinsertion of the magnetic tape cartridge itself.
In the meantime, as the cartridge misinsertion preventing mechanism of the magnetic tape library device cell which is designed to house a plurality of magnetic tape cartridges in series by aligning the directions thereof, those disclosed in Japanese Unexamined Patent Publication 2010-86578 (paragraphs 0005, 0021, FIG. 6A, FIG. 6B, FIG. 6C) (Patent Document 2) and the like, for example, are already known.
In general, as shown in FIG. 8, a magnetic tape cartridge 100 includes a tapered face d, which is formed by a face that is oblique to an insertion-side end face a and one side-face b and orthogonal to another one-end face c and is connected to the insertion-side end face a, the one side-face b, and the another one side-face c in width of less than the thickness of the magnetic tape cartridge 100 in the normal direction of the another one side-face c at a corner part X formed by the one side-face b adjacent to the insertion-side end face a, the another one side-face c adjacent to the insertion-side end face a and the one side-face b, and the insertion-side end face a in order to clarify the insertion direction of the magnetic tape cartridge 100.
Further, a magnetic tape library device cell 101 which houses a plurality of magnetic tape cartridges 100 in series by aligning the directions thereof includes a housing space 102 for housing the plurality of magnetic tape cartridges 100 and an insertion/extraction port 103 for inserting and extracting those magnetic tape cartridges 100 as shown in FIG. 9, for example.
As shown in FIG. 9, for example, a conventional cartridge misinsertion preventing mechanism disclosed in Patent Document 2 and the like is constituted with an entry preventing nail 104 fixed by being projected inside the housing space 102 from an inner wall 13 of the housing space 102 corresponding to the one side-face b of the magnetic tape cartridge 100 in a position slightly closer to the insertion/extraction port 103 than the insertion completed position of the insertion-side end face a of the magnetic tape cartridge 100 inserted first and where the isolated distance in the normal direction from the another one side-face c of the magnetic tape cartridge 100 in a housed state is within a range of the width of the tapered face d.
That is, through fixing the entry preventing nail 104 at the position where isolated distance from the another one side-face c of the magnetic tape cartridge 100 inserted first is within the range of the width of the tapered face d, the magnetic tape cartridge is allowed to be inserted into the insertion completed position that is at the farther position than the entry preventing nail 104 by providing no interference between a corner part X and the entry preventing nail 104 for the first magnetic tape cartridge 100 inserted in an appropriate direction as shown in FIG. 9. In the meantime, for the first magnetic tape cartridge 100 inserted in an inappropriate direction, a corner part located on an diagonal line of the corner part X on the insertion-side end face a of the first magnetic tape cartridge 100 or a corner part of an opposite-to-insertion-side end face e (see FIG. 8) is designed to interfere with the entry preventing nail 104 so as to prevent misinsertion of the magnetic tape cartridge 100.
However, such structure can only prevent the misinsertion of the magnetic tape cartridge 100 to be inserted first but cannot prevent misinsertion of the magnetic tape cartridges 100 inserted thereafter. For example, as shown in FIG. 9, even if the next magnetic tape cartridge 100 is inserted with its front and rear sides being reversed, the two magnetic tape cartridges 100 are finely housed within the housing space as long as the direction of the magnetic tape cartridge 100 inserted first is appropriate.
As a device capable for being converted into a magnetic tape library device as a technique for preventing misinsertion of the second cartridge and thereafter, a tape cartridge automatic loader disclosed in Japanese Unexamined Patent Publication Hei 11-45534 (paragraphs 0022, 0032, FIG. 6, FIG. 10) (Patent Document 3), for example, is known.
This is in a structure in which a misinsertion preventing module that is retreated by being pressed by a tilt face of a cartridge is placed inside a housing space, and the misinsertion preventing module is abutted against a straight-up face of the cartridge inserted inappropriately to prevent the misinsertion of the cartridge. Thus, under a specific condition, i.e., in a case where a plurality of cartridges are inserted one by one with a time interval, it is possible to appropriately prevent the misinsertion of the second cartridge and thereafter.
However, as shown in FIG. 9, for example, in a case where the opposite-to-insertion-side end faces e (see FIG. 8) of two magnetic tape cartridges 100 are abutted against each other and the first magnetic tape cartridge 100 is inserted in an appropriate direction, it is not possible to prevent the misinsertion of the magnetic tape cartridge inserted thereafter.
This is because a continuous flat face is formed by the side faces of the two magnetic tape cartridges 100 whose opposite-to-insertion-side end faces e (see FIG. 8) are being abutted against each other as shown in FIG. 9, i.e., the one side-face b of the magnetic tape cartridge 100 to be inserted first and the another side-face f of the magnetic tape cartridge 100 to be inserted next (corresponds to top face in FIG. 6 and FIG. 10 of Patent Document 3), so that a return action of the misinsertion preventing module cannot be executed by being impeded by the continuous flat face and insertion of the next magnetic cartridge 100 is allowed even when the opposite-to-insertion-side end face e (see FIG. 8) of the magnetic tape cartridge 100 inserted first passes the set position of the misinsertion preventing module.
While FIG. 9 shows a case where the first magnetic tape cartridge 100 is inserted in an appropriate direction and the next magnetic tape cartridge 100 is to be inserted with its front and rear sides being reversed and its opposite-to-insertion-side end face e being abutted against the opposite-to-insertion-side end face e of the first magnetic tape cartridge 100 as a way of example, the same issue is also generated in a case where the next magnetic tape cartridge 100 is to be inserted with its top and back faces being reversed and its insertion-side end face a being abutted against the opposite-to-insertion-side end face e of the first magnetic tape cartridge 100 and in a case where the next magnetic tape cartridge 100 is to be inserted with its front and rear sides as well as its top and back faces being reversed and its opposite-to-insertion-side end face e being abutted against the opposite-to-insertion-side end face e of the first magnetic tape cartridge 100. It is therefore an exemplary object of the present invention to provide a simple-structure cartridge misinsertion preventing mechanism capable of securely preventing misinsertion of magnetic tape cartridges, particularly misinsertion of the second magnetic tape cartridge and thereafter and misinsertion of the magnetic tape cartridges whose opposite-to-insertion-side end faces are abutted against each other, i.e., misinsertion even under a state where a continuous flat face is formed in the side faces of the magnetic tape cartridges, without requiring a complicated medium position detecting mechanism and an optical detection module.

Cartridge misinsertion preventing mechanism and magnetic tape library device cell


A mental impairment detection system and non-invasive method of detecting mental impairment of a user are provided. A test (e.g., an inhibitory reflex test or a sustained attention test) is administered to the user, brain activity in a frontal lobe of the user is non-invasively detected while the test is administered to the user, and a level of mental impairment of the user is determined based on the brain activity detected in the frontal lobe of the user.

The operation of transportation vehicles, such as cars, motorcycles, trucks, and airplanes, as well as the performance of high responsibility jobs, such as air traffic controllers and heavy machinery operators (e.g., a forklift or crane), by individuals who are temporarily mentally impaired due to the influence of chemical substances, such as drugs (prescription or recreational) and alcohol, sleep deprivation, or brain injury (e.g., stroke or concussion) is a major problem. Not only do such mentally impaired persons put their own lives at risk, they put innocent lives at risk as well. In addition to putting lives at risk, such mentally impaired individuals are subject to fines, license revocation or suspension, firing or suspension from employment, and criminal prosecution.
In many cases, individuals that are temporarily mentally impaired are not aware or are unsure of the extent of their mental impairment. There exists sobriety screening or monitoring systems that allow an individual to measure his or her own alcohol blood level, thereby providing such individual an indication of the extent of mental impairment due to alcohol consumption. However, such systems only measure the level of alcohol content, and do not actually measure the level of impairment, of the individual being tested, and thus, may not accurately determine the ability of the individual to operate transportation vehicles or perform high responsibility jobs. For example, alcohol tolerance levels may vary greatly amongst individuals, and more importantly, individuals with low alcohol tolerance levels may actually be mentally impaired to the extent that operating transportation vehicles or performing high responsibility jobs would be considered unsafe despite the fact the blood alcohol level of such individuals may indicate that they are not so impaired. Furthermore, such sobriety screening systems do not take into account non-alcoholic causes of temporary mental impairment or other various levels of mental impairment, such as prescription or recreational drugs, as well as pre-existing medical conditions caused by disease or injury that may mentally impair an individual that is not under the influence of alcohol.
There, thus, remains a need to determine the level that an individual is actually impaired with respect to operating transportation vehicles or performing high responsibility jobs.

Non-invasive systems and methods for detecting mental impairment


The invention relates to a novel CMP slurry composition used for polishing metals, the composition comprising: (a) a dispersion solution comprising an abrasive; and (b) an oxidizer. The slurry composition has a large particle count of less than about 150,000 particles having a particle size greater than 0.5 xcexcm in 30 xcexcL of slurry, which is achieved by filtering the slurry composition prior to use. Also, the inclusion of a chemical activity enhancer, such as, an amine and a corrosion inhibitor, results in the appropriate copper removal rate without increasing static etch rates.

The present invention relates to a chemical mechanical polishing slurry system used in semiconductor manufacturing. More particularly, the present invention relates to a chemical mechanical polishing slurry system that has a lower incidence of defects.
Semiconductors are typically made up of millions of active devices that are connected together via metal interconnections to form circuits and components. The active devices are interconnected by a well-known multilayer interconnect process. In a typical interconnect process, alternating layers of metal and dielectric are put on the silicon wafer by a variety of processes. After each layer is applied, a means is used to remove excess amounts of these layers and to assure both local and global planarity of the surface in preparation for the application of the next layer.
A common process used to accomplish these goals is chemical mechanical planarization (CMP). In this process, an aqueous solution containing various chemicals and suspended abrasive particles, namely, a slurry, is interposed between the wafer and a moving pad while pressure is applied. The combination of the mechanical effects of the abrasive particles, applied pressure, imposed relative velocity and the chemical effects which result from chemical reaction between the material being polished and constituents in the solution result in a synergistic enhancement of the polishing rate or material removal rate. That is, the material removal rate is higher than that produced by either the mechanical effects or chemical effects alone.
There are two general types of layers that can be polished. The first layer is interlayer dielectrics (ILD), such as, silicon oxide and silicon nitride. The second layer is metal layers, such as, tungsten, copper, aluminum, etc., which are used to connect the active devices.
In the case of CMP of metals, the chemical action is generally considered to take one of two forms. In the first mechanism, the chemicals in the solution react with the metal layer to continuously form an oxide layer on the surface of the metal. This generally requires the addition of an oxidizer to the solution, such as, hydrogen peroxide, ferric nitrate, etc. Thereafter, the mechanical abrasive action of the particles continuously and simultaneously removes this oxide layer. A judicious balance of these two processes obtains optimum results in terms of removal rate and polished surface quality.
In the second mechanism, no protective oxide layer is formed. Instead, the constituents in the solution chemically attack and dissolve the metal, while the mechanical action is largely one of mechanically enhancing the dissolution rate by such processes as continuously exposing more surface area to chemical attack, raising the local temperature (which increases the dissolution rate) by the friction between the particles and the metal, enhancing the diffusion of reactants and products to and away from the surface by mixing, and by reducing the thickness of the boundary layer.
A number of systems for chemical-mechanical polishing of copper have been disclosed. Kumar et al. in an article entitled xe2x80x9cChemical-Mechanical Polishing of Copper in Glycerol Based Slurriesxe2x80x9d (Materials Research Society Symposium Proceeding, 1996) disclose a slurry that contains glycerol and abrasive alumina particles. An article by Gutmann et al. entitled xe2x80x9cChemical-Mechanical Polishing of Copper with Oxide and Polymer Interlevel Dielectricsxe2x80x9d (Thin Solid Films, 1995) discloses slurries based on either ammonium hydroxide or nitric acid that may contain benzotriazole (BTA) as an inhibitor of copper dissolution. Luo et al. in an article entitled xe2x80x9cStabilization of Alumina Slurry for Chemical-Mechanical Polishing of Copperxe2x80x9d (Langmuir, 1996) discloses alumina-ferric nitrate slurries that contain polymeric surfactants and BTA. Carpio et al. in an article entitled xe2x80x9cInitial Study on Copper CMP Slurry Chemistriesxe2x80x9d (Thin Solid Films, 1995) disclose slurries that contain either alumina or silica particles, nitric acid or ammonium hydroxide, with hydrogen peroxide or potassium permanganate as an oxidizer.
There are a number of theories as to the mechanism for chemical-mechanical polishing of copper. An article by Zeidler et al. (Microelectronic Engineering, 1997) proposes that the chemical component forms a passivation layer on the copper, changing the copper to a copper oxide. The copper oxide has different mechanical properties than metallic copper, such as, density and hardness, and passivation changes the polishing rate of the abrasive portion. The above article by Gutmann et al. discloses that the mechanical component abrades elevated portions of copper and the chemical component then dissolves the abraded material. The chemical component also passivates recessed copper areas minimizing dissolution of those portions.
Planar Solutions has developed a basic slurry for the CMP of copper, tantalum and TEOS layers. This is described in a publication titled xe2x80x9cDevelopment of a 1:1:1 TA: Copper layer: TEOS layer slurry for Tantalum layer polishingxe2x80x9d in the proceedings of the CMP MIC conference, February 1999. In a two step process to CMP the copper layer, in the first step the slurry polishes the copper layer rapidly, while in the second step, the slurry polishes the tantalum layer, the copper layer, and the TEOS layer simultaneously. The prior art slurry was designed to have no selectivity towards these layers and the topography performance was excellent. The topography has been reported to be in the 100-300 xc3x85 range. However, the prior art slurry has two distinct disadvantages associated with it, namely, defectivity and oxide thinning or total copper loss.
The defectivity issue revolves around several chatter mark defects revealed in the copper layer after CMP. After polishing with the prior art slurry, the polished substrate, when viewed at 200xc3x97magnification at nine sites, had several hundred chatter mark defects (hereafter referred to as a normalized defectivity of 100). The chatter mark defects were deep and were cosmetically unacceptable.
The oxide thinning is primarily associated with the high removal rate of the TEOS layer. The prior art slurry removed the TEOS layer more rapidly than the tantalum layer or the copper layer. For example, typical removal rates were TEOS layer: 1500 xc3x85/min, tantalum layer: 600 xc3x85/min, and copper layer: 900 xc3x85/min. As a result of the high oxide thinning, thicker TEOS layers will have to be deposited, which will result in subsequent increased costs.
The present invention overcomes the disadvantages of the current metal slurry compositions so that defectivity and oxide thinning or total copper loss are significantly reduced and/or eliminated. The present invention also provides many additional advantages, which shall become apparent as described below.
The present invention relates to a novel CMP slurry composition used for polishing metals comprising (a) a dispersion solution comprising an abrasive; and (b) an oxidizer. The slurry composition has a large particle count of less than about 150,000 particles having a particle size greater than 0.5 xcexcm in 30 xcexcL of slurry, which is achieved by filtering the slurry composition prior to use. By controlling the particle size of the abrasive dispersion, through either filtration of the dispersion itself or the slurry composition before use, defectivity and oxide thinning/total copper loss problems are significantly reduced and/or eliminated. Also, the inclusion of a chemical activity enhancer, such as, an amine and a corrosion inhibitor, results in the appropriate copper removal rate without increasing static etch rates, which cause increased topography.
The slurry composition may also comprise at least one other component selected from the group consisting of: acids, chelating agents, fluorine-containing compounds, buffering agents, salts, and biological agents.
It has been found that by reducing the number of abrasive large particles, in combination with optimizing chemical activity, in a CMP slurry composition, defectivity and oxide thinning/total copper loss on the substrate being polished is significantly reduced and/or eliminated. The defectivity and oxide thinning/total copper loss depends on two critical factors: (1) the number of large particles present in the slurry composition, and (2) the chemical activity of the slurry composition.
For the purpose of this patent application, the term xe2x80x9cparticlexe2x80x9d includes, but is not limited to, colloids, aggregates and other fused combinations of particles, as well as agglomerates and other solely mechanically interwoven combinations of particles. xe2x80x9cLarge particle countxe2x80x9d is intended to mean a count of particles where the particles have a particle size greater than about 0.5 xcexcm. The term xe2x80x9cparticle sizexe2x80x9d is intended to mean an average diameter size of a distribution of particles.
To count particles and measure particle size, there are many suitable methods known in the art. Preferably, the particle count and size is measured by an Accusizer, manufactured, for example, by Particle Sizing Systems. To measure particle count and size using an Accusizer, an amount of sample containing particles is diluted with about 1 milliliter (mL) of water and then introduced into the Accusizer. The Accusizer then measures the particle count and size of the particles contained in the sample. The particle count is proportional to the amount of sample analyzed. For example, when analyzing about 30 microliters (xcexcL) of the slurry of the present invention, diluted with about 1 mL of water, in an Accusizer, less than about 150,000 particles having a particle size greater than about 0.5 (micrometers)xcexcm are measured. If 60 xcexcL of the same slurry of the present invention were diluted with 1 mL of water, the Accusizer would measure less than about 300,000 particles having a particle size greater than about 0.5 xcexcm.
The CMP slurry of the present invention comprises an abrasive dispersion and an oxidizer. The abrasive particles may be any material that is effective at removing metal and silicon layers. Silica is the abrasive material used in the present invention. The silica may be, for example, colloidal silica, fumed silica and other silica dispersions; however, the preferred silica is fumed silica. Preferably, the silica is present in the slurry in a concentration of about 4% to 10% of the total weight of the slurry. More preferably, the silica is present in a concentration of about 5% to 9% of the total weight of the slurry. Most preferably, the silica is present in a concentration of about 6.5% to 8% of the total weight of the slurry.
In addition, other ceramics, such as, for example, alumina (Al2O3), ceria (CeO2), and mixtures thereof may also be utilized as an abrasive in the slurry composition.
To reduce the number of large particles contained in the slurry composition, the slurry composition is filtered before its use. Preferably, the slurry composition is filtered at least once prior to its use. More preferably, the slurry composition is filtered at least three times prior to its use. Alternatively, the abrasive dispersion can be filtered prior to being admixed with the other chemical components that make up the slurry composition.
The slurry composition can be filtered using any filtration process known in the art. By way of example, the filtration process may include one or more stages of filtration in series starting with coarse filters ( i.e., bag filters) followed by cartridge type filters. Typically, filtration could begin with one or more very coarse ( i.e., 50 micron) filters and then be followed by one or more fine pore size filters (i.e., 0.5 micron). Filtration time can vary depending on the amount of the slurry composition to be filtered. For example, the slurry can be filtered at a flow rate between about 0.5 to 10 gallons per minute.
As a result of the filtration, chatter mark defects on a polished substrate are significantly reduced, as shown in Tables 1 and 2 below.
The slurries listed in Table 2, with the exception of the colloidal silica slurry, are fumed silica based slurries. All of the slurries, except for the A5012 Ta slurry, are KOH stabilized and include hydrogen peroxide and BTA. The A5012 Ta slurry is fumed silica based, but ammonia stabilized. The ammonia ion attacks copper reducing chatter mark defects. Unless noted otherwise, each slurry was filtered, resulting in different large particle counts in the slurry compositions.
When there is a lack of significant chemical activity, the defects varied directly with the number of coarse particles ( greater than 0.5 xcexcm) present. A slurry with a higher chemical activity, such as an acidic slurry or an ammonia based slurry, such as A5012, reduced the chatter mark defects significantly. A single patterned wafer exhibiting few chatter mark defects was polished using a fumed silica slurry, which was filtered several times and had a very low particle count, i.e., less than about 150,000 particles having a particle size greater than about 0.50 xcexcm, in a 30 xcexcL sample. This resulted in zero chatter mark defects on the polished wafer.
By reducing the fumed silica concentration in the slurry composition to about 6.5% to 8% of the total weight of the slurry, the TEOS layer removal rate dropped from 1500 xc3x85/min to about 1200 xc3x85/min. In addition, the copper and tantalum removal rates were reduced. To combat these reductions, the oxidizer concentration was systematically reduced, which resulted in an increased tantalum layer removal rate, as demonstrated by Table 3 below.
Hydrogen peroxide (H2O2) is used as the oxidizing agent in the present invention. Preferably the concentration of the H2O2 is from about 0.01% to 10% of the total weight of the slurry. When used with fumed silica, the H2O2 is present in a concentration from about 0.05% to 0.50% of the total weight of the slurry.
Other suitable oxidizing agents may be utilized. For example, potassium ferricyanide, potassium dichromate, potassium iodate, potassium bromate, vanadium trioxide, hypochlorous acid, sodium hypochlorite, potassium hypochlorite, calcium hypochlorite, magnesium hypochlorite, ferric nitrate, various ammonium salts such as ammonium persulfate, potassium permanganate, and mixtures thereof, are suitable oxidizing agents.
In order to further enhance the chemical activity of the slurry composition, additional chemicals may be added to the CMP slurry composition, including, for example, corrosion inhibitors, amines, stabilizing agents, surfactants, acids, fluorine-containing compounds, chelating agents, and salts.
Suitable corrosion inhibitors that may be added to the slurry composition include, for example, benzotriazole, 6-tolylytriazole, 1-(2,3-dicarboxypropyl)benzotriazole, carboxylic acids and mixtures thereof. The corrosion inhibitor may be present in the slurry in a concentration of about 0.001% to 10% and is preferably present in a concentration of about 0.003% to 0.05% of the total weight of the slurry. The preferred corrosion inhibitor is benzotriazole (BTA) and is most preferably present in a concentration of about 0.005% to 0.015% of the total weight of the slurry.
Suitable amines that may be added to the slurry composition include, for example, ammonia, hydroxylamine, monoethanolamine, diethanolamine, triethanolamine, diethyleneglycolamine, N-hydroxylethylpiperazine, and mixtures thereof. The amines may be present in the slurry composition in a concentration of about 0.001% to 10%, and are preferably present in a concentration of about 0.005% to 5% of the total weight of the slurry. The preferred amine is ammonia and is most preferably present in a concentration of about 0.01% to 0.03% of the total weight of the slurry.
It has been found that the inclusion of small amounts of a chemical activity enhancer, such as, ammonia and a corrosion inhibitor, such as, BTA, in the slurry composition results in the appropriate adjustment of the copper layer removal rate without any increase in static etch rates, which causes the topography to increase. This is demonstrated in Table 4 below for a slurry composition having about 6.5 wt. % abrasive particles, normalized 50 H2O2, and a pH of about 10.
In order to maintain the pH of the slurry composition, a stabilizing agent may be added so that the pH of the slurry is about 8 to 10.5. Suitable stabilizing agents include, for example, ammonium hydroxide and potassium hydroxide. These stabilizing agents may be present in the slurry in a concentration of about 0.1% to 5%, and more preferably in a concentration of about 0.2% to 1% of the total weight of the slurry.
Suitable surfactant compounds that may be added to the slurry composition include, for example, any of the numerous nonionic, anionic, cationic, or amphoteric surfactants known to those skilled in the art. The surfactant compounds may be present in the slurry composition in a concentration of about 0.05% to 1% and are preferably present in a concentration of about 0.07% to 0.5% of the total weight of the slurry. The preferred types of surfactants are nonionic, anionic, and mixtures thereof and are most preferably present in a concentration of about 0.075% to 0.4% of the total weight of the slurry.
Suitable acid compounds that may be added to the slurry composition, to adjust the pH of the composition, include, for example, formic acid, acetic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, lactic acid, hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, malic acid, tartaric acid, gluconic acid, citric acid, phthalic acid, pyrocatechoic acid, pyrogallol carboxylic acid, gallic acid, tannic acid, and mixtures thereof. The acid compound may be present in the slurry composition in a concentration of about 0.1% to 2% of the total weight of the slurry. The preferred acid is propanoic acid, most preferably in a concentration of about 0.2% to 0.5% of the total weight of the slurry.
It has been found that carboxylic acids, if added, may also impart corrosion inhibition properties to the slurry composition, in addition to adjusting the pH of the composition.
To increase the selectivity of tantalum and tantalum compounds relative to silicon dioxide, fluorine-containing compounds may be added to the slurry composition. Suitable fluorine-containing compounds include, for example, hydrogen fluoride, perfluoric acid, alkali metal fluoride salt, alkaline earth metal fluoride salt, ammonium fluoride, tetramethylammonium fluoride, ammonium bifluoride, ethylenediammonium difluoride, diethylenetriammonium trifluoride, and mixtures thereof The fluorine-containing compounds may be present in the slurry composition in a concentration of about 0.1% to 5%, and are preferably present in a concentration of about 0.25% to 1% of the total weight of the slurry. The preferred fluorine-containing compound is tetramethylammonium fluoride, most preferably in a concentration from about 0.3% to 0.8% of the total weight of the slurry.
Suitable chelating agents that may be added to the slurry composition include, for example, ethylenediaminetetracetic acid (EDTA), N-hydroxyethylethylenediaminetriacetic acid (NHEDTA), nitrilotriacetic acid (NTA), diethylklenetriaminepentacetic acid (DPTA), ethanoldiglycinate, and mixtures thereof. The chelating agents may be present in the slurry composition in a concentration of about 0.05% to 1%, and are preferably present in a concentration of about 0.1% to 0.75% of the total weight of the slurry. The preferred chelating agent is EDTA and is most preferably present in a concentration of about 0.15% to 0.5% of the total weight of the slurry.
Suitable salts that may be added to the slurry composition include, for example, ammonium persulfate, potassium persulfate, potassium sulfite, potassium carbonate, potassium propionate, ammonium nitrate, potassium hydrogen phthalate, hydroxylamine sulfate, and mixtures thereof. The salts may be present in the slurry composition in a concentration of about 0.1% to 5%, and are preferably present in a concentration of about 0.25% to 1% of the total weight of the slurry. The preferred salt is ammonium persulfate and is most preferably present in a concentration of about 0.3% to 0.75% of the total weight of the slurry.
The CMP method of the present invention involves a two step process wherein the CMP slurry composition is used to polish a substrate with at least one metal layer, such as, copper, tungsten, tantalum, aluminum, titanium, and combinations thereof. The CMP method reduces both the amount of defects and oxide thinning/total copper loss on the metal layers polished, as compared to a process employing a high copper removal rate slurry alone.
The substrate polishing process comprises the steps of: applying to a metal layer a slurry composition comprising a silica dispersion and an oxidizer, wherein the silica dispersion has a large particle count of less than about 150,000 particles having a particle size of greater than about 0.5 xcexcm in a 30 xcexcL sample; and chemically mechanically polishing the metal layer with the slurry composition.
This invention is explained below in further detail with reference to Example 1, which is not by way of limitation, but by way of illustration.

Chemical mechanical polishing slurry composition for polishing conductive and non-conductive layers on semiconductor wafers


An access method, a network device, and a mobile communication terminal are provided. The access method applied to the network device includes transmitting frequency information of a downlink frequency range and at least two uplink frequency ranges and a physical random access channel parameter.

In a related mobile communication system, uplink and downlink frequency bands in a Time Division Duplexing (TDD) technology have the same frequency range and the same frequency bandwidths; uplink and downlink frequency bands of a Frequency Division Duplexing (FDD) technology have the same frequency bandwidth and different frequency ranges, and uplink and downlink are used in pairs. Therefore, in the related art, frequency ranges of the uplink and downlink frequency bands of a cell are used in pairs, and frequency bandwidths of the uplink and downlink frequency bands are the same. In a Long Term Evolution (LTE)-Advanced technology, carrier aggregation is introduced. Bandwidths of uplink and downlink carriers may be configured differently through uplink carrier aggregation or downlink carrier aggregation. However, in a case that the carrier aggregation is applied to inter-cell aggregation, each cell participating in the carrier aggregation still needs frequency correspondence and the same bandwidth in uplink and in downlink, and does not support a transmission mode in which uplink and downlink frequency ranges do not correspond to each other and bandwidths in uplink and in downlink are different.
In a 5th-generation (5G) mobile communication system, a new spectrum mainly includes high frequencies and a frequency band of millimeter waves. However, the higher a frequency of a frequency band is, the worse an anti-fading performance is, resulting in poorer coverage performance. As can be seen from the above, a coverage performance of the 5G is poor. With application of a large-scale antenna and a beamforming technology, a coverage area of a network device at a downlink frequency band has been enhanced in some degree. However, an effective solution has not been proposed for a problem of a narrow coverage area of a mobile communication terminal at an uplink frequency band since a transmission mode in which the uplink and downlink frequency ranges in a cell do not correspond to each other and bandwidths in uplink and in uplink are different is not supported in the related art. Furthermore, with application of a downlink enhancement technology, difference between coverage areas at the uplink and downlink frequency bands is increasing.

Access method, network device, and mobile communication terminal

China Mobile Communication Co., Ltd Research Institute

China Mobile Communications Group Co., Ltd.


A print head device, which includes a plurality of image carrying bodies, a plurality of developing units, a plurality of charging units, and at least one intermediate transfer unit, is constructed as a unit assembly, and the unit assembly is inserted into and removed from image forming apparatus main body. The image forming apparatus contains a mechanism that the image carrying bodies are minutely movably supported by a frame of the unit assembly with a gap being located therebetween, and are positioned and fixed to a housing of the image forming apparatus main body.

1. Field of Invention
The present invention relates to an image forming apparatus such as a printer, a copying machine or a facsimile machine, for forming color and black/white images based on an image forming process, e.g., electrophotography, electrostatic recording system, ionography, magnetic recording system and the like. More particularly, the invention relates to an electrophotographic image forming apparatus of the tandem type which is provided with a plurality of photoreceptor drums and a plurality of image carrying bodies, and is free from color misregistration after it is commercially supplied and undergoes maintenance and is capable of forming images of high quality for a long period of time. Further, the invention relates to a small color electrophotographic image forming apparatus which is small in size and low in cost, and improved in the operability of an image forming unit.
2. Description of Related Art
Various types of xerographic based image forming apparatus for forming color and black/white pictures, such as printers and copying machines, have been proposed and marketed. In particular recently, much effort has been made to develop color printers with the spread of personal computers, internet, digital cameras, and the like. In the field of image forming apparatus, e.g., color printers, there is a strong demand for developing an apparatus which is capable of forming office-use color images, and is operable at a high speed, compact in size, and low in cost.
To form a color image of high quality by using image forming apparatus, such as a color printer, it is necessary to improve accuracy of color registration, i.e., a registration of color component images. That is, to form a color image, color component images of colors, e.g., cyan, magenta, yellow, and black, are formed on an image bearing member, and those color component images are accurately registered to one another and superimposed one upon another.
An image forming apparatus of the tandem type is known for the image forming apparatus, such as a printer. This type of image forming apparatus includes a plurality of image forming units with photoreceptor drums as image carrying bodies corresponding to colors of toner images to be formed, e.g., cyan, magenta, yellow and black. Those color component toner images are successively formed on the image carrying bodies (e.g., photoreceptor drums) of the image forming units. Those toner images are transferred on a recording sheet or an intermediate transfer member in a superimposing fashion.
The tandem type image forming apparatus includes a plurality (e.g., four) of image forming units for forming color component images. Therefore, to improve the accuracy of color registration of the color component images as formed by the image forming units, it is necessary to locate the color component images formed by the image forming units accurately in predetermined positions. To this end, the image forming units of the tandem type are arranged such that the accuracy of color registration, which is performed when the images formed by the image forming units are superimposed one on another, is improved by controlling the scan start timings of the main scan and the sub-scan by an image exposure unit, which forms an image on the image carrying body by a laser beam, the phase of the polygon mirror for scanning by the laser beam, or the position of the mirror for guiding the laser beam to the image carrying body.
In color electrophotography-based image forming apparatus of the type in which a plurality of image forming units including the image carrying bodies (photoreceptor drums) are provided for each color, it is a common practice that the image forming units may be replaced with new ones for each color, as disclosed in Japanese Utility Model laid-open No. 29148/1987. In some image forming apparatus, a replaceable system is employed in which the respective color image forming units are fixed to a single image forming unit positioning member, and the positioning member is then mounted on the main body, as disclosed in Japanese patent laid-open No. 36346/1996. Either system needs the replacement of several number of image forming units. Accordingly, this fact remarkably increases a mental strain of the user when he or she replaces the an image forming unit with another image forming unit. In a case where the image forming units are assembled into a unit and the support shafts of the image carrying bodies are positioned to the frame of the unit, the following problem arises: an accuracy of positioning the writing unit, the intermediate transfer unit for superimposing the color component images, and the image carrying bodies is deteriorated. In the image forming unit as disclosed in Japanese patent laid-open No. 78686/1998, the position accuracy of the laser-based writing unit and the image carrying bodies, and the position accuracy of the image carrying bodies and the image carrying body transfer drums which are in contact with the image carrying bodies greatly affect the accuracy of color misregistration. A problem of color misregistration arises in the image forming unit disclosed.
In most cases, the color registration of the apparatus main body is adjusted at a factory before it is delivered. When the image forming unit greatly affects the color misregistration, the adjustment equivalent to that at the initial state of the product at the factory is required in a maintenance work, e.g., the user replaces the image forming unit with a new one, after the apparatus is commercially supplied. In this case, to lessen the user""s load, some means to automatically adjust the color misregistration may be used additionally. A color misregistration adjusting technique is present which detects the result of superimposing the color component images by some means, and feeds back the detection result for adjustment. The technique needs a high accuracy detecting mechanism and adjusting mechanism. This fact results in remarkable increase of the apparatus cost. The color misregistration may be adjusted in a manner that the image formed is output, and a quantity of a color misregistration of the image is detected by the eye, and a color misregistration correction quantity based on the detection is input to the apparatus main body. In this approach, the adjusting accuracy is poor, however.
A color misregistration arises from a position accuracy of the image carrying bodies support shafts and a laser beam position accuracy of a ROS. A high position accuracy of several tens xcexcm is required for satisfying a tolerable level. It is actually difficult to satisfy the requirement of such a high position accuracy, and a common practice is to adjust the timings of the laser beams for the purpose of preventing color misregistration. Accordingly, in order to make the user free from those sequential adjusting steps when he replaces the image forming unit including the photoreceptor drum with a new one, it is necessary to exactly position and fix the image carrying bodies support shafts to the apparatus main body.
Before delivery from a factory, color misregistration is adjusted, in both the main scan and sub-scan directions of the ROS, on the basis of the image as finally printed out and according to the writing timings of the ROS and the readout timing clock frequency. The color misregistration depends greatly on the position accuracy of the photoreceptor drums. In spite of this fact, its adjustment is carried out by controlling electrical times, not by adjusting those positions. For this reason, it is necessary to accurately position the image carrying bodies support shafts to the main body.
The conventional image forming apparatus employs a C-path transport system in which a sheet transporting path is curved shaped like a C when viewed from the side of the apparatus. The C-path transport system has the following advantages, and is employed in particular by small desk-top printers.
1) The sheet transport path is short, a time taken from sheet feeding to sheet discharging is short, and the image forming is highly efficient.
2) If the sheet feeding direction is placed in the front surface of the image forming apparatus, the sheet transporting path is opened to the user side. Accordingly, a jam removal operation is easy.
3) The operation of replacing the image forming unit may be performed by opening the front cover or the upper cover. A space occupied by the image forming apparatus when the cover is opened is small.
In the color tandem apparatus containing a plurality of image forming units (photoreceptor drums), it is necessary to exactly position the image forming units (photoreceptor drums) to the main body in consideration of color misregistration or other problems. Further, the image forming units must be constructed so as to allow the user to replace them with other ones. In the C-path transport system, the image forming units are vertically arranged. Accordingly, in the structure where the image forming units are inserted into and removed from the main body in lateral directions parallel to the image carrying bodies support shafts or the unit is inserted into and removed from the main body in lateral directions parallel to the image carrying bodies support shafts as the sheet transporting directions, a space to allow the insertion and removal motions of the image carrying bodies in the image carrying bodies support shaft directions must be provided when taking into account the insertion and removal of the image forming units located in the lower part. Further, a cover opened for jam removal is different from a cover opened for the color tandem machine replacement, so that an advantage of restrictions on the machine installation space is impaired. For the insertion and removal of the image carrying bodies in the sheet transporting direction, an angle of the opening of the cover located on this side must be large, so that the apparatus installation space is large. A manual inserter, transporting rolls and the like are located upstream of a transfer section. If those are disposed at positions where the insertion/removal motion of the image forming unit located in the lower part is not hindered, the transporting distance is long, and the advantages of the C-path transport system is impaired. In Japanese patent laid-open No. 72983/1999, a plurality of image forming units, which are detachably attached to unit receivers formed in the apparatus main body, are inserted and removed horizontally or in lateral directions. Accordingly, the sheet transport path is long, and the advantages of the C-path transport is impaired.
In the image forming apparatus of the tandem type, a very expensive device is required to correct color misregistration of the apparatus after it is commercially supplied. If such an expensive device is not used, color misregistration adjustment will be difficult and its accuracy is extremely deteriorated.
Accordingly, an object of the present invention is to solve the above problems, to accurately position the image carrying bodies to prevent color misregistration, to lessen the mental strain of the user in maintenance work, and to prevent the charging performance and the developing performance of the image carrying bodies from being degraded, and to provide an image forming apparatus of good electric power feeding performance.
Another object of the present invention is to provide a technique to realize a mechanism for the C-path transport system, which is advantageously applied to a small printer, in a color tandem apparatus. In this case, extreme care must be exercised so as not to lower the color misregistration accuracy and not to deteriorate the operability.
Further subjects of the invention are:
(1) To find such an insertion/removal direction as not to hinder the insertion/removal motion of the image forming unit.
(2) To assemble the image forming units into a unit assembly and hence to improve the operability at the time of inserting and removing the image forming units.
(3) To construct such a structure as not to deteriorate the color misregistration.
(4) To reduce the apparatus cost and size by guiding the image carrying bodies support shafts.
(5) To save the widthwise space by commonizing the configuration of the apparatus main body.
(6) To prevent erroneous operations.
The invention is made to solve the problems. In accordance with a first aspect of the present invention, there is provided an image forming apparatus having an image forming unit, in which the image forming unit includes a plurality of image carrying bodies, the image forming unit is a unit assembly, and the unit assembly is formed to be detachable from a main body of the image forming apparatus. The term xe2x80x9cunit assemblyxe2x80x9d means an aggregation of the individual units of the image forming apparatus, which are arranged such that those units exhibit their functions. The unit assembly may be handled as one component.
The plurality of image carrying bodies may be a plurality of latent image carrying bodies or a plurality of intermediate transfer members. The plurality of image carrying bodies may also be a plurality of latent image carrying bodies and one intermediate transfer member. Further, the plurality of image carrying bodies may be one latent image carrying body and one intermediate transfer member or a plurality of latent image carrying bodies and a plurality of intermediate transfer members. In a preferred embodiment, the unit assembly formed to be detachable from the main body of the image forming apparatus is disposed in the main body of the image forming apparatus by downwardly moving the unit assembly. The preferred embodiment involves the following construction: A portion on which the unit assembly is placed is pulled out of the image forming apparatus main body in the substantially horizontal direction, and in this state the unit assembly is put on a unit assembly placement location by downwardly moving the unit assembly, and then the pulled out one is returned to its original position. With such a construction, the portion includes the plurality of image carrying bodies, so that the weight of it is increased. As a result, the insertion or installation of the unit assembly is easy.
The unit assembly may include a handle on an upper surface thereof. This feature makes it easier to install the unit assembly into the image forming apparatus main body. In this case, the unit assembly formed to be detachable from the main body of the image forming apparatus may be disposed in the main body of the image forming apparatus by a single action of downwardly moving the unit assembly. This feature is desirable since it remarkably reduces a mental strain of the user when he replaces the unit assembly with another unit assembly.
A positioning member for positioning the unit assembly when the unit assembly is disposed in the main body of the image forming apparatus may be integrally molded. With this feature, the unit assembly may be accurately positioned, to thereby effectively prevent color misregistration. In that case, the image forming apparatus may further have an exposure unit for forming a latent image on the image carrying body, in which the exposure unit is supported by the positioning member integrally molded. The plurality of image carrying bodies and the exposure unit are supported by the common positioning member. Accordingly, color misregistration may be prevented accurately. In this case, the positioning member and the housing of the exposure unit may be made of the same material. The linear expansion coefficients of the positioning member and housing are equal to each other. The occurrence of the color misregistration, caused by the influence of temperature of an ambience in which the image forming apparatus is placed, may be suppressed effectively. A material of the positioning member and housing is preferably a material formed by mixing glass fiber into polycarbonate, for example.
Preferably, in the image forming apparatus, the image carrying bodies are supported by the image carrying body supporting members, at least one of the supporting members is minutely movably supported by a frame of the unit assembly with a gap, and when the unit assembly is disposed in the main body of the image forming apparatus, the supporting member is positioned and fixed to a housing of the main body of the image forming apparatus. More preferably, in the image forming apparatus, the image carrying bodies are supported by the image carrying body supporting members, at least one of the supporting members is minutely movably supported by a frame of the unit assembly with a gap, and when the unit assembly is disposed in the main body of the image forming apparatus, the positioning member positions and fixes the supporting member. The unit assembly preferably includes a plurality of developing units.
In the image forming apparatus, it is preferable that the developing units are pressed against surfaces of the image carrying bodies to be positioned so that predetermined gaps are present between the developing units and the surfaces of the image carrying bodies.
In the image forming apparatus, the developing units receive drive forces from a developing-unit driving device located in the main body of the image forming apparatus, the developing-unit driving device is different from image carrying body driving device, and in the developing unit, gears are arranged such that a tangential load of the gear, which operates when the developing-unit driving device is driven, does not produce such a component of force as to cancel a pressing force applied to a drum surface of each developing unit.
The unit assembly may include a plurality of charging units. In the image forming apparatus, the charging units are positioned and fixed to shafts of the image carrying bodies, the charging units have mechanisms which are minutely movably supported on a frame of the unit assembly with a gap, and the mechanisms prevent the charging units from turning in a circumferential direction of the image carrying bodies.
The image carrying bodies may be earthed and include ground lines, which interconnect shafts of the image carrying bodies by way of electrically conductive elastic members.
The image forming apparatus may further have a charging device which feeds electric power to a charging unit from outside of the unit assembly by way of a frame of the unit assembly, in which the charging device includes an electrically conductive elastic member which couples a conductive member for feeding electric power to the charging unit located on a frame of the unit assembly and a charging-unit supporting member.
The intermediate transfer members may be cylindrical intermediate transfer drums. The intermediate transfer drums may include a primary transfer drum onto which an image is transferred from the image carrying body and a secondary transfer drum onto which the image is transferred from the primary transfer drum and the secondary transfer drum may be a drum for transferring the image thereon onto a sheet of paper.
Furthermore, the intermediate transfer drums may be supported by intermediate transfer drum shafts, at least one of the intermediate transfer drum shafts may be minutely movably supported by a frame of the unit assembly with a gap, and the shafts of the intermediate transfer drums have mechanisms for positioning and fixing the shafts of the intermediate transfer drums to a housing of a main body of the image forming apparatus when the unit assembly is installed in the main body of the image forming apparatus.
The unit assembly may have four image carrying body drums, two primary intermediate transfer drums, and one secondary intermediate transfer drum. Preferably, the shaft of the secondary intermediate transfer drums is press-fitted into the frame of the unit assembly.
According to another aspect of the present invention, there is provided an image forming apparatus having an image forming unit, in which the image forming unit includes a plurality of image carrying bodies, the image forming unit is a unit assembly in which axial lines of the plurality of image carrying bodies are arranged parallel to one another in a plane containing the axes, the unit assembly is detachable from a main body of the image forming apparatus in a direction of a line perpendicular to the axes in the axes-contained plane.
The image carrying bodies are preferably supported by a single frame. Each of the image carrying bodies may be positioned to the main body of the image forming apparatus. The main body may have first guides for guiding ends of image carrying body support shafts to position the unit assembly to the main body of the image forming apparatus. The first guides may include oblique branch paths for guiding the image carrying body support shafts to fixing positions.
At least one protrusion, which is different from the image carrying body support shafts, may be provided on a frame of the unit assembly and second guides for guiding the protrusion may be provided on a housing of the main body of the image forming apparatus. With this feature, the unit assembly is inserted into or removed from the image forming apparatus main body, while being guided by the first and second guides. Accordingly, the inserting and removing operations of the unit assembly are free from its inclination and twisting.
The image carrying bodies may be photoreceptor drums or may be intermediate transfer drums and photoreceptor drums. In the image forming apparatus of the invention, a sheet feeding portion may be located at a lower position, a sheet discharging portion may be located at an upper position, a direction in which a transfer member is transported at the time of image transferring may be in a range of from 45xc2x0 to 90xc2x0 with respect to a horizontal direction, and the axes-contained plane may be a substantially vertical plane with respect to the horizontal direction. The reason why the transporting direction of the transfer member is set to be in a range of from 45xc2x0 to 90xc2x0 is that an ideal transporting direction angle is as close to the vertical direction as possible, but at least 45xc2x0 or larger is desirable for the transporting direction.

Image forming apparatus with detachable image forming unit assembly


Discussed are an organic light emitting display and a method for fabricating the same to improve color purity and efficiency. The organic light emitting display includes a substrate having first to third sub-pixels, first and second electrodes formed on the substrate, the first and second electrodes facing each other, a red light emitting layer formed in the first sub-pixel between the first and second electrodes, a green light emitting layer formed in the second sub-pixel between the first and second electrodes, and a blue common light emitting layer formed in the first to third sub-pixels between the first and second electrodes, wherein a thin film layer formed between the first electrode and the blue common light emitting layer and contacting the blue common light emitting layer includes a blue host.

1. Field of the Invention
The present invention relates to an organic light emitting display and a method for fabricating the same to improve color purity and efficiency.
2. Discussion of the Related Art
The recent advent of information-dependent age has brought about rapid development in the display field that visually displays electrical information signals. In this regard, a variety of flat panel display shaving superior properties such as slimness, low weight and low power consumption have been developed.
Examples of flat panel displays include liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), organic light emitting displays (OLEDs) and the like.
In particular, an organic light emitting display spontaneously emits light, which has advantages of rapid response speed, superior luminous efficacy, excellent brightness and wide viewing angle, as compared to other flat panel displays. Such an organic light emitting display includes an anode and a cathode which face each other such that a light emitting layer is interposed therebetween. Holes injected from the anode recombine with electrons injected from the cathode in the light emitting layer to form electron-hole pairs, i.e., excitons. Light is emitted by energy generated upon transition of the excitons to a ground state.
In a general organic light emitting display, a configuration in which a blue light emitting layer is formed commonly in red, green and blue sub-pixels by deposition is suggested in order to simplify a fabrication process. However, when the blue light emitting layer is formed in the red and green sub-pixels, upon emission of red and green light from the red and green light emitting layer, blue spectrum is also emitted and color purity of red and green light is disadvantageously deteriorated.
In addition, when a blue light emitting layer formed by a general deposition process contacts a hole transport layer formed by a solution process, lifespan and efficiency of the blue light emitting layer are disadvantageously deteriorated due to surface non-uniformity between an interface of the hole transport layer and an interface of the blue light emitting layer.

Organic light emitting display and method for fabricating the same