A lithographic projection system has an illumination system. A plurality of directing elements reflect different sub-beams of an incident projection beam into adjustable, individually controllable directions. By using of re-directing optics any desired spatial intensity distribution of the projection beam can be produced in its cross-sectional plane.

1. Field of the Invention
The present invention relates to a lithographic projection apparatus.
2. Description of the Related Art
The term xe2x80x9cpatterning devicexe2x80x9d as here employed should be broadly interpreted as referring to device that can be used to endow an incoming radiation beam with a patterned cross-section, corresponding to a pattern that is to be created in a target portion of the substrate. The term xe2x80x9clight valvexe2x80x9d can also be used in this context. Generally, the pattern will correspond to a particular functional layer in a device being created in the target portion, such as an integrated circuit or other device (see below). An example of such a patterning device is a mask. The concept of a mask is well known in lithography, and it includes mask types such as binary, alternating phase-shift, and attenuated phase-shift, as well as various hybrid mask types. Placement of such a mask in the radiation beam causes selective transmission (in the case of a transmissive mask) or reflection (in the case of a reflective mask) of the radiation impinging on the mask, according to the pattern on the mask. In the case of a mask, the support structure will generally be a mask table, which ensures that the mask can be held at a desired position in the incoming radiation beam, and that it can be moved relative to the beam if so desired.
Another example of a pattering device is a programmable mirror array. One example of such an array is a matrix-addressable surface having a viscoelastic control layer and a reflective surface. The basic principle behind such an apparatus is that, for example, addressed areas of the reflective surface reflect incident light as diffracted light, whereas unaddressed areas reflect incident light as undiffracted light. Using an appropriate filter, the undiffracted light can be filtered out of the reflected beam, leaving only the diffracted light behind. In this manner, the beam becomes patterned according to the addressing pattern of the matrix-addressable surface. An alternative embodiment of a programmable mirror array employs a matrix arrangement of tiny mirrors, each of which can be individually tilted about an axis by applying a suitable localized electric field, or by employing piezoelectric actuators. Once again, the mirrors are matrix-addressable, such that addressed mirrors will reflect an incoming radiation beam in a different direction to unaddressed mirrors. In this manner, the reflected beam is patterned according to the addressing pattern of the matrix-addressable mirrors. The required matrix addressing can be performed using suitable electronics. In both of the situations described hereabove, the patterning device can comprise one or more programmable mirror arrays. More information on mirror arrays as here referred to can be seen, for example, from U.S. Pat. Nos. 5,296,891 and 5,523,193, and PCT patent applications WO 98/38597 and WO 98/33096, which are incorporated herein by reference. In the case of a programmable mirror array, the support structure may be embodied as a frame or table, for example, which may be fixed or movable as required.
Another example of a pattering device is a programmable LCD array. An example of such a construction is given in U.S. Pat. No. 5,229,872, which is incorporated herein by reference. As above, the support structure in this case may be embodied as a frame or table, for example, which may be fixed or movable as required.
For purposes of simplicity, the rest of this text may, at certain locations, specifically direct itself to examples involving a mask and mask table. However, the general principles discussed in such instances should be seen in the broader context of the patterning device as hereabove set forth.
Lithographic projection apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, the patterning device may generate a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto a target portion (e.g. comprising one or more dies) on a substrate (silicon wafer) that has been coated with a layer of radiation-sensitive material (resist). In general, a single wafer will contain a whole network of adjacent target portions that are successively irradiated via the projection system, one at a time. In current apparatus, employing patterning by a mask on a mask table, a distinction can be made between two different types of machine. In one type of lithographic projection apparatus, each target portion is irradiated by exposing the entire mask pattern onto the target portion at once. Such an apparatus is commonly referred to as a wafer stepper. In an alternative apparatus, commonly referred to as a step-and-scan apparatus, each target portion is irradiated by progressively scanning the mask pattern under the projection beam in a given reference direction (the xe2x80x9cscanningxe2x80x9d direction) while synchronously scanning the substrate table parallel or anti-parallel to this direction. Since, in general, the projection system will have a magnification factor M (generally  less than 1), the speed V at which the substrate table is scanned will be a factor M times that at which the mask table is scanned. More information with regard to lithographic devices as here described can be seen, for example, from U.S. Pat. No. 6,046,792, incorporated herein by reference.
In a known manufacturing process using a lithographic projection apparatus, a pattern (e.g. in a mask) is imaged onto a substrate that is at least partially covered by a layer of radiation-sensitive material (resist). Prior to this imaging, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures, such as a post-exposure bake (PEB), development, a hard bake and measurement/inspection of the imaged features. This array of procedures is used as a basis to pattern an individual layer of a device, e.g. an IC. Such a patterned layer may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemo-mechanical polishing, etc., all intended to finish off an individual layer. If several layers are required, then the whole procedure, or a variant thereof, will have to be repeated for each new layer. Eventually, an array of devices will be present on the substrate (wafer). These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc. Further information regarding such processes can be obtained, for example, from the book xe2x80x9cMicrochip Fabrication: A Practical Guide to Semiconductor Processingxe2x80x9d, Third Edition, by Peter van Zant, McGraw Hill Publishing Co., 1997, ISBN 0-07-067250-4.
For the sake of simplicity, the projection system may hereinafter be referred to as the xe2x80x9clens.xe2x80x9d However, this term should be broadly interpreted as encompassing various types of projection system, including refractive optics, reflective optics, and catadioptric systems, for example. The radiation system may also include components operating according to any of these design types for directing, shaping or controlling the beam of radiation, and such components may also be referred to below, collectively or singularly, as a xe2x80x9clensxe2x80x9d. Further, the lithographic apparatus may be of a type having two or more substrate tables (and/or two or more mask tables). In such xe2x80x9cmultiple stagexe2x80x9d devices the additional tables may be used in parallel or preparatory steps may be carried out on one or more tables while one or more other tables are being used for exposures. Dual stage lithographic apparatus are described, for example, in U.S. Pat. No. 5,969,441 and WO 98/40791, incorporated herein by reference.
A projection apparatus, such as used in lithography, generally includes an illumination system, referred to hereafter simply as an illuminator. The illuminator receives radiation from a source, such as a laser, and produces a projection beam for illuminating an object, such as the patterning device (e.g. a mask on a mask table). Within a typical illuminator, the beam is shaped and controlled such that at a pupil plane the beam has a desired spatial intensity distribution. This spatial intensity distribution at the pupil plane effectively acts as a virtual radiation source for producing the projection beam. A Following a first pupil plane, the radiation is substantially focused by a lens group referred to hereafter as xe2x80x9ccoupling Lensxe2x80x9d. The coupling lens couples the substantially focused radiation into an integrator, such as a quartz rod. The function of the integrator is to improve the homogeneity of the spatial and/or angular intensity distribution of the projection beam. The spatial intensity distribution at the pupil plane is converted to an angular intensity distribution at the object being illuminated by the coupling optics, because the pupil plane substantially coincides with the front focal plane of the coupling optics. Controlling the spatial intensity distribution at the pupil plane can be done to improve the processing latitudes when an image of the illuminated object is projected onto a substrate. In particular, spatial intensity distributions with dipole, annular or quadrupole off-axis illumination profiles have been proposed to enhance the resolution and other parameters of the projection, such as sensitivity to projection lens aberrations, exposure latitude and depth of focus.
A known illuminator comprises an optical system referred to hereafter as xe2x80x9czoom-axiconxe2x80x9d. The zoom-axicon is a device that adjusts the intensity distribution at the pupil plane. Radiation from the source passes through a first optical element such as, for example, a diffractive optical element (DOE), which generates an angular intensity distribution. Next, the radiation beam traverses a zoom lens. In the back focal plane of the zoom lens a spatial intensity distribution occurs that generally is suitable to serve as a secondary light source in the pupil plane. Hence the back focal plane of the zoom lens typically substantially coincides with the pupil plane (i.e. the front focal plane of the coupling optics). The outer radial extent of the spatial intensity distribution at the pupil plane can be changed by changing the focal length of the zoom lens. However, the zoom lens must have two degrees of freedom, one to change the focal length of the zoom lens and a second to change the position of the principal planes such that when the focal length changes, the back focal plane remains located at the pupil plane of the illuminator. Due to this functionality, the zoom lens typically consists of several (e.g. at least three) separate lenses in series, several of which are movable. As mentioned above, by tuning the focal length of the zoom lens, the radial extent of the intensity distribution at the pupil plane can be set. In the following, any preselected, preferred spatial intensity distribution at the pupil plane may be referred to as an xe2x80x9cillumination settingxe2x80x9d.
An axicon, which is located near the pupil plane, generally consists of two elements having complimentary conical shaped faces. The axicon is used to generate annular spatial intensity distributions, or other spatial intensity distributions with substantially no intensity around their center, i.e. no on-axis illumination. By tuning the distance between the two conical faces of the axicon, the annularity can be adjusted. When the axicon is closed, i.e. the gap between the conical faces is zero, conventional, (i.e. disc-like) illumination settings can be produced. With a gap between the conical faces, an annular intensity distribution results, with the inner radial extent of the annulus determined by the distance between the two conical faces. On the other hand the zoom lens determines the outer radial extent and thus the width of the annulus. Preselected inner and outer radial extents of the intensity distribution are often referred to as "sgr"-settings, in particular the "sgr"-inner settings and the "sgr"-outer setting, respectively. Here, "sgr"-inner and "sgr"-outer are a measure for the ratio of the radius in question to the maximum radius of the pupil.
The term xe2x80x9czoom-axiconxe2x80x9d as employed here should be interpreted as referring to a module comprising a zoom lens and an axicon.
Multiple illumination settings can be generated by various device in the known illuminator, for example by modifying the first optical element in front of the zoom lens, such as to appropriately shape the angular intensity distribution, or by inserting aperture plates or blades into the beam path, for instance near a pupil plane, and so on. Further information on a known zoom-axicon module and multipole mode generation are given (for example) in U.S. Pat. No. 6,452,662, incorporated herein by reference.
In the known illuminator, described above, it is apparent that to produce the desired range of illumination settings the zoom-axicon module will generally have several (e.g. five or more) optical components, which can make it expensive to produce, particularly given the fact that several of the elements must be independently movable. A further problem is that the lenses comprising the zoom lens and the two conical elements of the axicon represent a considerable thickness of lens material and a large number of surface interfaces. This means that the transmission efficiency can be poor due to absorption, reflection, inefficient coatings, degradation effects and contamination. This problem is exacerbated by the demand for imaging ever smaller features at higher densities, which requires the use of radiation with shorter wavelengths, such as 193, 157, 126 nm or even EUV (e.g. 5-20 nm). The efficiency of suitable transmissive materials, such as CaF2 and quartz, decreases at shorter wavelengths due to increased absorption and no materials are known that are sufficiently transmissive for EUV radiation. The effectiveness of the optical coatings of the components also typically decreases at shorter wavelengths and degradation effects generally become worse. Thus, overall, a significant throughput reduction can occur, due to decreased transmission. Another problem is that the known illuminator occupies a relatively large volume in the lithography apparatus. This in turn can lead to excess bulk in the machine, and increased manufacturing costs (particularly when using material such as CaF2).
As mentioned above, spatial intensity distributions with dipole, annular or quadrupole off-axis illumination profiles can enhance the projection properties. The choice of the profile depends on, amongst others, the respective application of the lithographic process. To provide a desired non-standard illumination mode for a given application, requires dedicated optical devices which must be specially designed at considerate effort and expense.
EP 0 744 641 A describes an illumination system for use in a lithography apparatus which uses a deformable mirror to improve the uniformity of illumination of the mask.
EP 0 486 316 A describes various different lithography apparatus including a variety of different arrangements for providing dipole and quadrupole illumination settings. These include arrangements using fiber bundles whose exit points are moveable to define the pole positions. Other arrangements use a mirror shiftable between two positions during an exposure or between shots of a multishot exposure.
An aspect of the present invention is to provide an improved lithography apparatus with an illuminator which avoids or alleviates the above problems. A further object is to provide devices which can be used to generate nearly any desired intensity distribution of the projection beam.
According to one aspect of the present invention there is provided a lithographic apparatus including a radiation system to provide a projection beam of radiation; a support structure for supporting a patterning device, the patterning device serving to pattern the projection beam according to a desired pattern; a substrate table to hold a substrate; a projection system to project the patterned beam onto a target portion of the substrate; wherein the radiation system comprises an illumination system configured to define the intensity distribution of the projection beam, wherein the illumination system comprises a steering device to individually steer different parts of an incoming beam into different directions to provide a desired angular intensity distribution of the projection beam at the patterning device, the steering device comprising a plurality of discrete mirrors, each for steering a part of the incoming beam and whose orientation can be controlled individually to direct the corresponding part of the incoming beam into a desired direction.
Another aspect of the present invention the plurality of discrete mirrors. Preferably, the discrete mirrors can be controlled to direct their corresponding part of the incoming beam into (substantially) any desired direction. The resulting angular intensity distribution can then be transformed into a spatial intensity distribution, for example by a focusing lens. Examples for a directing element are a reflecting element, which reflects the incident radiation into a direction or range of directions, and a diffractive element, which diffracts and thereby diverges the incident radiation. Any other type of element which is capable of directing radiation into a specific direction or range of directions or into plural directions can be used as a directing element, as long as the direction or the directions can be controlled. The control can be performed by any suitable way, for example mechanically to orient the directing element and/or electrically to directly or indirectly change the directing properties and/or the orientation of the directing element. Other methods for influencing the directing element and thereby setting the direction or directions are possible, such as methods using electromagnetic radiation or fields.
In recent times, micro-electromechanical and micro-opto-electro-mechanical systems (MEMS and MOEMS) have been developed for use as optical switches in devices for optical data transmission. Some of these MEMS comprise arrays with more than 1000 microscopic mirrors wherein each of the mirrors can be tilted in two different planes perpendicular to each other. Thus, radiation incident on such devices can be reflected into (substantially) any desired direction of a hemisphere. Such an array of reflective elements can be used as the plurality of discrete mirrors and are individually oriented to reflect projection radiation into different pre-determined directions.
An important advantage of the present invention lies in the fact that it can be applied to EUV radiation to provide desired intensity distributions. It has up to now not been possible to provide a zoom-axicon or equivalent device that would function with EUV radiation.
In a particular embodiment of the invention, the steering device includes a first faceted mirror, each of the discrete mirrors being a facet of the first faceted mirror and serving to project an image of a radiation source onto a selected facet of a second faceted mirror by control of the orientation thereof. In this arrangement, the first faceted mirror acts as a field mirror and a fly""s-eye reflector, creating a large number of virtual sources on the second faceted mirror which are then redirected to overlap on the mask, providing the desired uniformity of illumination. Preferably, the second faceted mirror is in a plane conjugate with a pupil plane of the projection system so that the illumination of the second faceted mirror determines the illumination mode of the mask. Thus, the illumination mode can be controlled by controlling the orientation of the facets of the first faceted mirror to illuminate selected ones of the facets of the second faceted mirror. This avoids the loss of beam intensity that would occur if the illumination mode is set by selective masking in a pupil plane.
The present invention is not limited to the case that the radiation system provides a single projection beam of radiation. Rather, different sub-beams or bundles of sub-beams can be generated at different locations and can be steered by the steering device to produce the desired angular intensity distribution. Furthermore, the projection beam or at least one of the projection beams can be split up to form separate sub-beams before reaching the directing elements. This means that the angular intensity distribution may be somewhat influenced by the manner in which the projection beam or projection beams is generated or manipulated before reaching the directing elements, but the control of the directing elements enables the user to produce the desired angular intensity distribution by choosing from a wide range of possible distributions. In particular, it is preferred that the directing elements can be controlled to direct each incident part of the projection radiation into (substantially) any direction of a hemisphere.
As described above, a desired spatial intensity distribution is to be produced in some cases. In these cases, it is preferred to produce a corresponding angular intensity distribution and to use a re-directing element to at least a part of the steered projection beam to produce the desired spatial intensity distribution in a cross-section of the projection beam, in particular in a focal plane. In particular, if focusing optical elements are used, such as a convex lens, each of the different directions of radiation propagation (of the produced angular intensity distribution) corresponds to one particular area of the spatial intensity distribution, in particular to one specific local point in a focal plane.
Different shapes and/or profiles of such a spatial intensity distribution such as annular, quadrupole, dipole and (soft) multipole, have been proposed. The present invention enables the user of a lithographic projection apparatus to produce any desired spatial intensity distribution, for example with arbitrary, definable shapes.
According to a preferred aspect of the invention, at least some of the sub-beams are steered and re-directed so that they correspond to spots or dashes of radiation in the cross-section in which the spatial intensity distribution is defined. Thus, the spatial intensity distribution has a profile with a discrete character. Depending on the size of the spots and/or dashes, and thereby depending on the size of the range of directions into which a single sub-beam is steered by the steering device, the spatial intensity distribution can comprise zones where the intensity is zero or almost zero (non-illuminated or dark zones) between illuminated areas.
In a preferred embodiment, the range of directions into which a single sub-beam propagates is influenced so that there is a sufficiently continuous intensity distribution. It is possible to influence the respective sub-beam or beams before the beam reaches the directing element and/or afterwards. In one particular embodiment, the sub-beams are steered so that they each propagate essentially to a single point. The points can be the same or different for the different sub-beams. One advantage of this embodiment is that the sub-beam can easily be adjusted to be incident on the directing element in the correct place. Further, undesired boundary effects due to radiation which is incident at the boundaries of the directing element can be reduced or avoided. For example, if the directing element is a reflective element with a given size of a reflective area, the arrangement can easily be adjusted so that the sub-beam is incident on the reflective element in the central zone of the reflective area.
To increase the range of propagation directions of the steered sub-beam, a diffuser device, such as a diffuser plate, can be used. However, this also may affect the polarization of the sub-beam and can make it difficult or impossible to exploit the polarization in subsequent stages.
In another embodiment, the sub-beam or beams are therefore manipulated before reaching the directing element or elements. In particular, the respective sub-beam is manipulated so that the steered sub-beam propagates into a defined range of propagation directions. For example, this can be done using a concentrating element to concentrate the sub-beam onto the directing element. The concentration also has the advantage that the sub-beam is incident on the directing element at the correct place, e.g. the central zone of a reflective area.
In addition or alternative to the embodiments described before, the range of propagation directions of the sub-beam or beams can be increased using the directing element or elements. In particular, the reflective surface area of a reflective element can be shaped accordingly, for example to have a convex shape.
The term xe2x80x9csub-beamxe2x80x9d as here employed should not be interpreted in a limiting way regarding the intensity distribution of the beam or beams before reaching the directing elements. Rather, the respective beam can be a single beam with a continuous intensity distribution, but, at the same time, can be considered to comprise a bundle of sub-beams. At least some of the sub-beams may become individual beams, separated from other parts of the beam, after being steered by the steering device. In any case, each steered sub-beam corresponds to a related part of the originally generated projection beam or beams.
Another aspect of the invention is that a variety of intensity distributions of the projection beam can be produced without the need to design corresponding optical arrangements especially for each one particular illumination setting and/or to replace at least parts of an existing optical arrangement. In particular, intensity distributions can be produced which previously existed only in theory.
According to a further aspect of the invention there is provided a device manufacturing method including providing a substrate at least partially with a layer of radiation-sensitive material; providing at least one projection beam of radiation; modifying the intensity distribution of the projection beam; using a patterning device to endow the modified projection beam with a pattern in its cross-section; projecting the patterned beam of radiation onto a target which comprises at least a part of the radiation-sensitive material, wherein the modification of the intensity distribution of the projection beam includes controlling the direction into which the radiation propagates, wherein the projection beam comprises a plurality of sub-beams, wherein at least some of the sub-beams are steered into different directions using a plurality of directing elements, and wherein the directing elements are individually controlled to direct the corresponding sub-beam into a desired direction.
According to still a further aspect of the invention there is provided a control system for controlling the intensity distribution of a beam of radiation for use in lithography including a calculation unit for calculating, based on a given intensity distribution of the beam, the necessary modifications to be made to the given distribution to produce a desired intensity distribution; an input device to input information about the desired intensity distribution; an output device to output a plurality of control signals to a plurality of directing elements which are capable of re-directing parts of the beam; wherein the calculation unit is adapted to calculate the control signals so that the directing elements can be controlled to modify the given intensity distribution of the beam to an angular intensity distribution which corresponds to the desired intensity distribution.
The calculation unit calculates the control signals based on a given intensity distribution. In particular, the given intensity distribution is applied in a projection beam of radiation which is used repeatedly to project the same pattern onto respective radiation-sensitive areas of one or more than one substrate. In one scenario, the given intensity distribution will be the same for each projection period, which may be interrupted by time periods with no illumination of radiation-sensitive material. However, it is also possible to employ different intensity distributions one after the other, using the same plurality of directing elements. In this case, the control system outputs different sets of control signals to the plurality of directing elements in order to change the angular intensity distribution between two projection periods.
In particular if the directing elements are electrically controlled, the illumination setting can be changed very quickly, due to the small mass and inertia of single, individually controllable directing elements compared to the mass and inertia of whole sets of optical elements, such as sets of diffractive optical elements with many microlenses. Thus, it is now possible to change the illumination setting between two flashes of illumination in acceptable time and to employ different intensity distributions alternatingly on a substrate.
According to a further aspect of the present invention there is provided a control system for controlling the intensity distribution of a beam of radiation for use in lithography including a calculation unit for calculating, based on a given intensity distribution of the beam, the necessary modifications to be made to the given distribution to produce a desired intensity distribution; an input device to input information about the desired intensity distribution; an output device to output a plurality of control signals to a plurality of discrete reflectors which are capable of re-directing parts of the beam, wherein the calculation unit is adapted to calculate the control signals so that the orientation of the discrete reflectors can be controlled to modify the given intensity distribution of the radiation beam to an angular intensity distribution which corresponds to the desired intensity distribution.
The control system may also be provided with an input device to receive the actually obtained mirror positions and/or pupil distribution so as to effect a closed loop control of the minor position and/or pupil distribution. The pupil distribution may be measured as described in European Patent Application No. 00307558.7, which is hereby incorporated by reference.
According to still a further aspect of the invention there is provided a computer program for producing a desired spatial intensity distribution of a beam of radiation for use in lithography, wherein an angular intensity distribution of radiation propagation of the beam corresponds to a spatial intensity distribution in a cross-section of the beam; and a steering device can be controlled to form an angular intensity distribution for any desired spatial intensity distribution by re-directing parts of the beam; the computer program comprising a code adapted to calculate the necessary state of the steering device and/or the control signals for controlling the steering device to form the angular intensity distribution which corresponds to the desired spatial intensity distributions.
In a preferred embodiment, an arbitrary spatial intensity distribution in a cross-section of the beam can be defined and the code is adapted to calculate the necessary state of the steering device and/or the control signals to form the corresponding angular intensity distribution.
In general, it is not possible to produce any theoretically possible angular intensity distribution. In particular, if the steering device includes directing elements as described above, there will be some discrete character of the intensity distribution due to the fact that each directing element directs the corresponding part of the beam into a limited range of directions only (see above). Depending on the number of directing elements, on their characteristic properties, and other factors, the discrete character of the intensity distribution will be more or less pronounced. It is preferred that the code of the computer program take the discrete character into account and calculate the necessary state of the steering device and/or the control signals which result in the closest approximation of the angular intensity distribution which is equivalent to the desired spatial intensity distribution.
Preferably, in order to increase the number of spatial intensity distributions which can be produced by transforming the angular intensity distribution to the corresponding spatial intensity distribution, the optical elements (e.g. zoom lens) which transforms the angular intensity distribution to the spatial distribution can be modified and/or exchanged. In this case, the computer program must have access to the amended transformation behavior. In a preferred embodiment, the code is adapted to choose between different transformation arrangements and/or properties of transformation arrangements and are adapted to calculate not only the state of the steering device and/or the control signals for controlling the steering device, but are also adapted to calculate the corresponding transformation arrangement which produces the desired spatial intensity distribution. For example, the transformer may include a zoom lens and the code are then adapted to choose or calculate an appropriate value of the focal length of the zoom lens.
Alternatively, or as an added feature, it is possible that the code can choose between different arrangements for influencing the projection beam before it reaches the steering device.
Although specific reference may be made in this text to the use of the apparatus according to the invention in the manufacture of ICs, it should be explicitly understood that such an apparatus has many other possible applications. For example, it may be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal display panels, thin-film magnetic heads, etc. One of ordinary skill will appreciate that, in the context of such alternative applications, any use of the terms xe2x80x9creticlexe2x80x9d, xe2x80x9cwaferxe2x80x9d or xe2x80x9cdiexe2x80x9d in this text should be considered as being replaced by the more general terms xe2x80x9cmaskxe2x80x9d, xe2x80x9csubstratexe2x80x9d and xe2x80x9ctarget portionxe2x80x9d, respectively.
In the present document, the terms xe2x80x9cradiationxe2x80x9d and xe2x80x9cbeamxe2x80x9d are used to encompass all types of electromagnetic radiation, including ultraviolet radiation (e.g. with a wavelength of 365, 248, 193, 157 or 126 nm) and EUV (extreme ultra-violet radiation, e.g. having a wavelength in the range 5-20 nm), as well as particle beams, such as ion beams or electron beams.

Lithographic apparatus, device manufacturing method, device manufactured thereby, control system, computer program, and computer program product


A display panel and a manufacturing method thereof are provided. The display panel has a display area, a non-display area, and a bendable connection area being located between the display area and the non-display area and connecting the display area with the non-display area. The display panel includes a substrate; an inorganic insulating layer disposed on the substrate, wherein in the bendable connection area, a plurality of recesses are defined in the inorganic insulating layer; an organic filling layer filled in the plurality of recesses in the inorganic insulating layer and having a concave curved surface; and a wiring layer disposed on the inorganic insulating layer, wherein a concave curved surface formed on the wiring layer corresponds to the concave curved surface of the organic filling layer in each of the recesses.

An organic light emitting diode (OLED) display panel includes a main display area (including pixels, touch electrodes, etc.), a surrounding non-display area (including a gate driving circuit, a patterned interconnection circuit, etc.), and a display control module. It is required for two areas to be connected by wires arranged in a connection area. In order to implement narrow bezels in the OLED display panel, the wire area is folded, so that the surrounding non-display area is placed below the main display area, and a distance between the main display area and borders of the OLED device is shortened. However, when the connection area through which the wires pass is bent at a large angle, various layer components (for example, a wiring layer) in the connection area are subjected to stresses and are liable to be broken, which results in increased impedance of the wires or even short circuiting.
Therefore, it is necessary to develop a display panel in which a bendable connection area through which wires pass between a display area and a non-display area can withstand great stresses, thereby reducing breakage risks.

Display panel and method for manufacturing same

Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd.


An input buffer includes a first driving circuit, a second driving circuit, a pull up circuit, and a pull down circuit. The first driving circuit is arranged for driving a first input signal to generate an output signal. The second driving circuit is arranged for driving the output signal. The pull up circuit is arranged for selectively controlling the second driving circuit to pull up the output signal according to the first input signal and a second input signal. The pull down circuit is arranged for selectively controlling the second driving circuit to pull down the output signal according to the first input signal and the second input signal.

1. Field of the Invention
The present disclosure relates generally to an input buffer, and more specifically, to an input buffer free from cross point skews.
2. Description of the Prior Art
Input buffers are commonly used in a wide variety of digital circuits. There are also several types of input buffers. Single-ended input buffers have a single input signal applied to a buffer to actuate the buffer to transit when a first input signal transits through a predetermined voltage level. A single-ended input buffer may also compare the first input signal with a reference voltage, so that a transition occurs at the output of the input buffer when the first input signal crosses the reference voltage. There are also complementary input buffers, where a pair of complementary signals causes the output of the buffer to transit when one of the pair of complementary signals crosses the level of the other input signal.
These types of input buffers are generally adopted in digital circuits to perform a number of useful functions, such as providing a high input impedance which prevents undue loading coupled to their inputs. They can also provide conditioning signals applied to internal circuits so that internal signals may have well defined logic levels and transition characteristics. Notwithstanding the benefits provided by input buffers, they are not free from side effects. For example, input buffers may be utilized as delay cells for propagating signals in a high speed digital circuitry, but if undesirable cross point skews occur, this will induce a large current.

Input buffer with current control mechanism

Elite Semiconductor Memory Technology Inc.


An asphalt aggregate paver (1) for asphalting a surface (116) to be asphalted includes an asphalt aggregate receiving hopper (2), width-wise spreading means (4) for distributing the aggregate over the surface (116), and conveyor means (6) arranged between the receiving hopper (2) and the spreading means (4) for feeding said spreading means (4), by conveying said aggregate from the hopper to said spreading means (4) in a longitudinal direction (L). The paver further includes mixing means (8), which are a separate element of said conveyor means (6). The mixing means (8) are arranged between said receiving hopper (2) and said spreading means (4), and the mixing means (8) are movable with respect to the conveyor means (6) for stirring the aggregate when it is conveyed. The mixing means (8) are arranged outside and after the receiving hopper (2).

In the process of asphalting a public thoroughfare, it is necessary to spread the asphalt aggregate uniformly width-wise across the thoroughfare in order to then compact it.
In the invention, when the term "aggregate" is used, it refers to an asphalt aggregate.
The machinery intended for spreading asphalt aggregate over the public thoroughfare to be asphalted is known in the art as a paver. The purpose of a paver is to spread or scatter a uniform layer of agglomerate as it moves forward across the entire width of the machine which must subsequently be compacted by a suitable road roller working behind the paver.
The asphalt agglomerate comes from asphalt production sites located far away from the public thoroughfare that is being asphalted. Dump trucks that are open in the upper part and simply covered with a tarp are used to transport the agglomerate. The purpose of the tarp is to reduce temperature losses of the aggregate as much as possible between the production site and the public thoroughfare to be asphalted. The tarp also has the purpose of preventing the aggregate to be eventually harmed. Nevertheless, temperature losses are unavoidable and always occur to a greater or lesser extent.
A conventional dump truck for asphalt may transport several tons of aggregate in each trip. Dump trucks often transport in the order of 25 tons of product.
Due to the considerable mass that is transported, cooling takes place in the outermost layer of the aggregate mass. On the contrary, the inner part of the mass virtually remains at a constant temperature and loses little temperature until it is used for the asphalting process.
The asphalt aggregate production temperature is between 160 and 180° C. In turn, the optimal on-site application temperature is in the order of 140° C. Despite the fact that the inner part of the aggregate mass contained in the dump truck may maintain a suitable temperature above the suitable temperature, it is not uncommon for the surface layer to cool down to 100° C.
Temperatures in the asphalt aggregate mass that are too low before said mass is spread over the public thoroughfare to be asphalted lead to a deficient asphalting quality. Above all, if the spreading temperature is heterogeneous and low, the compacting process by means of the road roller is also more deficient. This leads to minimal irregularities on the asphalted surface that facilitate early deterioration of the public thoroughfare.
Therefore, the more homogeneous and higher the temperature of the aggregate during its application, the better the asphalting quality.
An asphalting method shown in FIG. 1 for asphalting large surfaces, and more particularly for asphalt wearing courses, is known in the state of the art.
The direction of spreading the aggregate corresponds to the forward movement direction of the machines of FIG. 1, depicted by arrow A.
A dump truck 100 with the asphalt aggregate mass is located in the front. The dump truck 100 deposits the aggregate mass, not shown in detail, in a first hopper 104 of an asphalt transfer machine, referred to in the art as a transfer machine 102. The aggregate mass for filling the first hopper may amount to 7 tons. In this particular method, worm screws mixing the aggregate mass in order to homogenize its temperature are arranged inside this first hopper 104. This method involves certain cooling of the aggregate mass.
After the homogenization process, the aggregate mass is conveyed by means of a first conveyor belt 106 to the rear part of the transfer machine 102.
The first conveyor belt 106 drops the asphalt mass inside a second hopper 110 of a paver 108, the aggregate mass having a homogeneous temperature. Inside this second hopper 108 there is mounted a second conveyor belt, not shown, which drops the aggregate onto a first worm screw 112 that distributes it width-wise across the surface 116 to be asphalted.
Behind the first worm screw 112 there is provided a level 114 that is in charge of distributing the aggregate more uniformly width-wise across the surface, in the forward movement direction.
Simultaneously, a road roller, which is not shown in the drawings and which circulates behind the paver, is in charge of the final compaction of the asphalted surface.
The asphalting train, i.e., the assembly that moves together formed by the dump truck 100, transfer machine 102, and paver 108, moves forward together until the dump truck 100 has dumped its entire contents into the transfer machine 102.
When the dump truck 100 is empty, it is moved away from the transfer machine 102 and a new dump truck 100 is provided for feeding the transfer machine 102 with more aggregate.
This solution is complex and requires an enormous investment in machinery. This has a direct effect on the asphalting cost and makes the public work unnecessarily more expensive.

Asphalt aggregate paver for asphalting a surface to be asphalted


A bit for horses comprising a central element, suitable for being inserted into a horse's mouth, and a pair of side rings, each side ring being connected to a respective end of the central element for connecting to the reins is provided. The central element is made of a plastic material and the ends of the central element are overmolded on coupling portions of the respective side rings.

As is well known, a horse bit generally comprises a central element, for example made of metal, possibly articulated, suitable for insertion into the mouth of the horse, and at least one pair of side rings, each attached at one end of the central element for connecting to the reins.
In one known embodiment, each ring is free to slide through a hole made in the end of the central element.
In order to protect the lip of the horse from contact with the ring and, in particular, to prevent the lip from getting caught at the coupling point between the central element and the ring, e.g. in the ring hole, a bit guard is fitted on each end of the central element. Such bit guard is in practice a disc wherein is made a circular opening in which the central element is inserted.


The invention relates to a method for removing a plurality of raised places of contact made of a meltable metal, such as tin or indium or an alloy, such as tin-containing solder, silver-containing solder or lead-containing solder, the meltable metal being meltable above a first temperature limit, the places of contact being surface-distributed over a substrate. It is also possible to form vaulted domes on a plurality of metallic support segments which are located on one of the surfaces of a substrate. The invention aims at reducing production costs, particularly at removing a soldered layer once applied. If defective contact places occur, a plurality of the raised contact places, particularly substantially all contacts, are at least in substantial portions melted off from the substrate by contacting them with a molten metal. Between the substrate and the support segments distributed over the substrate and a surface of the molten metal an organic fluid may be present, the organic fluid being provided as a covering layer only and evaporating off the substrate surface, after the vaulted domes have been formed.

The invention relates to a method for removing a plurality of raised places (spots, points) of contact of a meltable metal, such as tin or indium or an alloy, such as tin-containing solder, silver-containing solder or lead-containing solder, said meltable metal being meltable above a first temperature limit, said places of contact being surface-distributed over a substrate. The invention also relates to a method for forming vaulted domes on a plurality of metallic support segments which are distributed over one of the surfaces of a substrate.
In order to explain the problem solved by the methods of the invention, it is noted that not only flat conductive domes provide raised places of contact—also designated as "menisci" which are applied onto metallic support segments—, but that also stronger raised metallic structures can be applied on metallic support segments, said structures being used as solder balls or contact bumps for a flip-chip contact, compare the publication "Semiautomatic Solder Ball Bumper (SB2) by Pac Tech and the publication "Solder Ball Bumper (SB2)—A flexible manufacturing tool for 3-dimensional sensor and microsystem packages", Kasulke, Schmidt, Titerle, Bohnaker, Oppert, Zakel, published in IEMT Europe 1998, FIG. 6 and FIG. 8 in cross-section. Said raised places of contact are manufactured by several different methods, e.g. by laser or by (re-) shaping in an oven, after a preceding placement of a print of smaller solder particles which are melted in said oven, to provide the described raised places of contact in the form of balls. Usually, their height is substantially larger than that of the metallic support segments which are distributed over the substrate. A not completely avoidable probability that metallic bridges are formed by solder balls growing over to other solder balls, caused by too thick layers of flow medium, or that individual solder balls are generally missing, makes the use of the substrate technically impossible, because certain contact places are either not contacted or have a shortcut already prior to being contacted.
A further defective contact can occur due to the fact that a too large quantity of the solder forming said contact bump was applied on the substrate, thus causing an asymmetry of the formed raised contact places, said contact places possibly showing asymmetries in height as well as in a lateral extension, similar to the defects at certain, usually individual metallic support segments, as described before.
Substrates, particularly for forming wafers, are usually too precious to deny the use of the complete substrate if individual portions are damaged by applying the raised contact places upon preparing the contact. Therefore, an inexpensive solution has to be found to repair these contacted substrates which have been damaged during contact. In this respect, a specific solution has already been proposed according to the prior art, namely individually repairing individual contact places as SBB Repair Station (compare the above mentioned publication "Solder Ball Bumper (SB2)", FIG. 10 with the associated description). One single laser impulse is used for obtaining a reflow of the defective contact point and for removing the melted and softened solder bump by using a vacuum. Simultaneously, a nitrogen atmosphere is used to avoid an oxidation of the remaining solder cap on a laterally limited support segment. A basic technical problem solved by the invention is to reduce production cost, particularly to allow a removal of a solder once applied on a substrate, when defects occur, large raised places of contact not being (selectively) located at the positions of the metallic support segments, but, by forming bridges, providing a contact structure which no longer allows a regular use of the substrate, for example as a contacted wafer.
According to the invention, several contact places can be repaired together, such that at least a substantial part of the individual contact places is removed by melting off, said melting taking place in a molten metal, and no individual places of contact have to be removed individually and successively by local heating.
According to the invention, the substrate and all contact places are contacted with a molten metal to remove the complete pre-contacting in an inexpensive and timesaving way, to start from a new status quo and to again coat the substrate with raised places of contact. Said repairing method is a removal of a preceding contact in combination with an option to start the new contact at a state, at which all metallic support segments, which continue to be present, have the same design. This concern, both the contact places not having been contacted by a raised solder ball, and the contact places undergoing a shortcut with at least one further contact place due to an inexactly positioned solder ball.
By melting off, the solder of the raised contact point is taken up by the molten metal. Domes of small height which remain on said support segments receive substantially the metal or the metal alloy of which said molten metal consists. At the same time, said option allows also for repair of defectively contacted substrates by exchanging the first solder which has already solidified, and replacing said solder by the solder corresponding to the molten metal, particularly the molten metallic alloy, which is present in the bath.
When the two metals, particularly the two metal alloys are identical, i.e. the metal of the raised places of contact and the metal of the melted bath, the substances are only removed and not exchanged. At least substantial parts of the already solidified raised places of contact on the substrate are, however, removed, the described domes remaining as "menisci" of small height.
The method is suitable for both de-bumping, i.e. removing of already existing bumps, which bumps are the raised contact places, but it is also suitable for a first time coating of support segments which have not yet been coated. Coating can be performed by applying the molten metal which is present in the bath, but coating can also be performed by removing and newly applying the mentioned molten metal.
Additionally, no more than a covering layer of an organic fluid can for example be applied on the substrate, said covering layer as a film having a small thickness with respect to the substrate. Due to the small thickness of said fluid layer (a thin layer), said layer evaporates after having contacted the molten metal due to the vapor pressure, so that a subsequent cleaning step of the support segments coated for the first time or of the support segments coated again after removal of the pre-contacting and of the associated substrate is not required. Production or repair therefore becomes less expensive. A substantially smaller volume of the fluid applied particularly as a polyalcohol, like glycerol, is used which fluid has evaporated after the described process. In general, the invention avoids the use of a bath of considerable volume with respect to the described fluid.
A first temperature limit is to be understood such that a meltable metal is to be removed, but the substrate is not to be melted. Raised contact places, which are usually made of solder, are meltable at temperatures of below 200° C. (usually below 250° C.). When using glycerol, the organic fluid used has a boiling temperature of 290° C. Similar or comparable substances should have a boiling temperature of above 250° C. When the molten bath is made of an identical metal (particularly as a metal alloy), said first temperature limit also refers to said metal which should accordingly be at least at or above said temperature limit to allow the raised contact places to be melted off and taken up from the substrate.
The distributed arrangement of the described raised contact spots or of the metallic support segments carrying said spots concerns a distribution of the basic contact over a large surface, which are in turn each provided on a metallic basic pad which allows a contact with the interconnecting paths of the substrate when provided as wafers. Said large-surface distribution is a starting point or basis of the invention for proposing a large-area removal by melting off from the substrate.
In accordance with the invention, the raised contact places can be removed substantially completely or completely, and at the same time, their material property can be exchanged.
Suitable substrates can be the substrates also described in the prior art, for example wafers, printed cards, printed boards or ceramic substrates.
As far as a metal is mentioned in the following discussion, a metal alloy is always included. This is valid for both the raised places of contact and the molten metal in the bath. As a bath both a stationary melt, which is contacted by a relative movement with the contact bumps to be removed, and a melt which is at least partly in motion and towards which the substrate with the raised contact places to be removed is moved, can be used. A lowering in a vertical direction corresponds to a practically simultaneous lateral or surface removal of all contact bumps. A relative movement in a horizontal direction in which the substrate approaches a wave-shaped or surge-shaped vertically protruding metal bath corresponds to a band-shaped removal of the raised contact places which is performed successively, but uniformly with regard to the complete surface.
The residence time for an at least contacting immersion or for an approaching movement is determined, to have sufficient time available for melting off the raised contact places and for maintaining or actually providing the remaining dome coating on the support segments.
The thin layer of the medium selected in accordance with the invention evaporates from the substrate surface substantially without residue during contacting with the molten metal. Said film can be applied by spraying or by a vapor atmosphere in the sense of sputtering. When the support segments are provided with raised contact places of a meltable metal already prior to being contacted with the molten metal, said film comes to rest as a thin fluid layer between the substrate and the support segments distributed over said substrate. When raised contact places of a meltable metal have not yet been provided on the support segments, said fluid film also covers the support segments themselves.
A vapor coating can be applied on the substrate simultaneously with the contacting of the metal bath; however, the atmosphere can extend only so far in front of the metal melt that the thin, film-like application of the organic fluid is obtained by a passage or a movement of the substrate with the support segments through said atmosphere.
Said organic fluid can satisfy the same conditions and can be made of the same materials as described in EP 781 186 B1.
The fluid covers the substrate as a covering layer in the form of a film, the film surface which faces away from said substrate directing towards the atmosphere and contacting it. Before being contacted with the molten metal, said support segments can either be covered by said organic fluid film or by said raised contact bumps to be removed; in both cases, the covering layer is formed between the substrate as well as the support segments distributed over said substrate and the surface of the bath. Said formation can also be achieved by spraying before contacting the metal melt.
The use of the fluid layer provided as a covering layer only, which due to its film shape cares for a minimum volume of the fluid to be used, can not only be applied on the substrate by spraying or sputtering, it can also be present as a thin layer on the surface of the metallic bath, or it can be formed during the metallic contact, when the evaporated organic fluid is present in the atmosphere above said bath. All embodiments used achieve a minimum volume quantity of the auxiliary processing fluid and dispensability of an additional cleaning step. Further effects of said fluid in connection with the solder to be applied or removed and with the support segments on the substrate showing a high wettability are described in detail in the prior art (uniformity of the surface structure, reducing effect on the surface, and increase of the wettability of the solder). Moreover, when removing (melting off) said raised solder spots, there is an additional advantageous aspect, namely of supporting the pinch of a reduced surface tension when melting the metal to be removed from the substrate into a molten metal which has a substantially larger volume, so that a substantially uniform formation of menisci on all limited support segments is achieved.
An example may explain the relative proportions: When a wafer has for example a thickness of 600 μm, and the support segments on the substrate have a height of between 5 μm and 10 μm, the covering layer of auxiliary fluid, which is provided as a film, has a film thickness of 50 μm to 200 μm, particularly in a range of 100 μm, said thickness also depending on the height of the raised contact places which, in a range of between 10 μm and 100 μm, can occur as ball-shaped contact bumps. This explains the definition of de-bumping according to which said contact bumps are removed from a surface of a substrate.

Method for ablating points of contact (debumping)


A power supply circuit which generates driving voltages for an electro-optic device having a plurality of common electrodes and a plurality of segment electrodes with the use of multi-line driving in which four lines of common electrodes are simultaneously selected. The driving voltages are first through seventh driving voltages in which an i-th (2≦i≦5, and i is an integer) driving voltage is higher than an (i+1)th driving voltage. The power supply circuit includes: a common electrode driving-voltage generator circuit which generates the first and seventh driving voltages used for selection of the common electrodes at a positive side and a negative side on the basis of the fourth driving voltage; and a segment electrode driving-voltage generator circuit which generates the fourth driving voltage, the second and third driving voltages used for the segment electrodes at the positive side on the basis of the fourth driving voltage, and the fifth and the sixth driving voltages used for the segment electrodes at the negative side on the basis of the fourth driving voltage. The segment electrode driving-voltage generator circuit changes and outputs output potentials of only the third and fifth driving voltages from among the second through sixth driving voltages, while a voltage difference between the third and fourth driving voltages is kept equal to a voltage difference between the fourth and the fifth driving voltages.

The present invention relates to a power supply circuit, a driving device, an electro-optic device, an electronic apparatus, and a method of supplying driving voltages.
In a simple-matrix type liquid crystal panel (an electro-optic device, in a broad sense), improvement in the response speed is attempted with a multi-line (Multi Line Selection, hereinafter abbreviated to MLS) driving method of simultaneously selecting a plurality of common electrodes (scanning electrodes, in a broad sense), and increasing in contrast and reduction in power consumption are attempted.
In this MLS driving method, an interval of selection period, in which a selection voltage is applied to a common electrode in one frame period, is narrowed and on the other hand, the same common electrode is selected a plurality of times in one frame period. Accordingly, the selection voltage of the common electrode can be lowered, and an average transmissivity of pixels can be improved, thus improving contrast of a liquid crystal panel. For this reason, the driving voltage for segment electrodes (signal electrodes, in a broad sense) is determined corresponding to a scanning pattern (an applied pattern, a selection pattern) of the selection voltage of common electrodes to be simultaneously selected. Then, turned on or off of a pixel is controlled by an effective voltage applied to the liquid crystal device in one frame period.
In the case where a simple-matrix type liquid crystal panel is driven with the MLS driving method of simultaneously selecting four lines of common electrodes, if a non-selection voltage for common electrodes and a center voltage VC for the driving voltage of segment electrodes are made in common, seven levels of voltages (V3, V2, V1, VC, MV1, MV2, MV3) will be required.
FIG. 18 shows a relationship of the seven levels of voltages in the case where the simple-matrix type liquid crystal panel is driven with the MLS driving method of simultaneously selecting four lines of common electrodes.
Here, the voltages V3 and MV3 are the selection voltages of the common electrode. The voltage VC is the non-selection voltage of the common electrode, and is the driving voltage for the segment electrode. The voltages V2, V1, MV1, and MV2 are the driving voltages for the segment electrode.
The voltage difference between the voltage V3 and the center voltage VC is denoted by v3, the voltage difference between the voltage V2 and the center voltage VC by v2, and the voltage difference between the voltage V1 and the center voltage VC by v1. At this time, the voltage difference between the center voltage VC and the voltage MV3 is v3, the voltage difference between the center voltage VC and the voltage MV2 is v2, and the voltage difference between the center voltage VC and the voltage MV1 is v1. Here, the voltage difference between the voltage V2 and the voltage V1 (=the voltage difference between the voltage MV1 and the voltage MV2) is equal to the voltage difference between the voltage V1 and the center voltage VC (=the voltage difference between the center voltage VC and the voltage MV1). International Patent Publication No. WO 97/22036 is an example of related art.
If the above-described driving voltages are applied to the segment electrode in an ideal waveform, the same display quality (the same density, for example) is obtained for any display pattern.
However, there is produced dullness in the voltage waveform applied to the liquid crystal device itself, due to the own load of the liquid crystal device, the wiring resistance, or the like. For this reason, the effective voltage applied to the liquid crystal device becomes different from the ideal voltage depending on display patterns, thus deteriorating the display quality.

Power supply circuit, driving device, electro-optic device, electronic apparatus, and method of supplying driving-voltages


In a control unit, a method, a computer program and a computer program product for operating an internal combustion engine in the context of a combined direct and manifold injection, fuel is injected by at least one first injection valve into an induction manifold and/or by at least one second injection valve directly into a combustion chamber for combustion. In at least one predefined operating state of the internal combustion engine, fuel is only injected by the at least one first injection valve into the induction manifold for a predetermined number of successive combustion cycles. In a subsequent combustion cycle, fuel is injected by the at least one first injection valve into the induction manifold and by the at least one second injection valve directly into the combustion chamber or only by the at least one second injection valve directly into the combustion chamber.

PCT International Published Patent Application No. WO 2006/009313 describes a control device for an internal combustion engine, which is used for injecting the fuel by a manifold injection and a direct injection, an injection ratio between the manifold injection and the direct injection being determined as a function of a speed of the internal combustion engine, a load factor, and of a temperature of a coolant of the internal combustion engine. In this context, a minimum injection quantity is always ensured for the direct injection in order to prevent the injection valve used for the direct injection from being clogged by deposits which accumulate on the direct injection valve at high temperatures. A cooling of the direct injection valve is effected by the minimum injection quantity.
The minimum injection quantity for the direct injection must be increased as a function of the temperature of the internal combustion engine in order to provide adequate cooling of the direct injection valve. Moreover, the homogeneity of the air-fuel mixture must be ensured regardless of whether the internal combustion engine is operated solely by direct injection, solely by manifold injection, or by a combination of direct injection and manifold injection. Certain operating states of the internal combustion engine require selecting a smallest possible minimum injection quantity for the direct injection. For example, a very small minimum injection quantity is selected for the direct injection in order to promote the homogeneity of the air-fuel mixture.

Method and device for operating an internal combustion engine in the context of a combined direct and manifold injection, a computer program, a computer program product


An underwater wave energy converter (WEC) (10) has a piston (32) that reciprocates up and down as recurring waves (22) pass over. Downward motion of the piston (32) drives the rods or plungers (50b) of a multiplicity of hydraulic jacks (50) to pressurize hydraulic fluid in an energy conversion system. Ultimately, the energy conversion system powers one or more hydraulic motors (511, 512) that drive an electric generator (510) or multiple generators. A sensor system (25) detects characteristics of in-coming waves such as by detecting changes in pressure as in-coming waves (22) pass over the sensor system (25). The sensors can be mounted on the ocean floor seaward from the WECs (10), and a control computer system (231) calculates characteristics of the in-coming waves such as wave height and speed data, and uses the data to control aspects of the WECs (10) and other components of the energy conversion system.

The present invention relates to ocean wave energy converters, particularly for application near shore, and more particularly to a novel system of wave energy converters having hydraulic components for converting energy of recurring waves to electric energy.
The publications listed below are expressly incorporated by reference herein and describe prior approaches to convert energy of ocean waves to another form of usable energy, such as electric energy:
Burns: International Patent Publication No. WO 2004/0003380;
Burns: International Patent Publication No. WO 2007/019640;
Gardner: U.S. Pat. No. 6,256,985;
Stromotich: Canadian Patent Application No. 2 408 855.


A unit for an aircraft thruster is provided that includes a first ferrule configured to be attached to a second ferrule and a first connection flange configured to be secured to a second corresponding connection flange secured to the second ferrule. The connection flange includes a portion forming a plane extending along a radial direction with respect to the first ferrule. A link between the first ferrule and the corresponding connection flange is offset to a distance from said plane corresponding to a length for damping a shear-generating flexural moment, generated by fluxes of forces passing through the first ferrule.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
A nacelle, belonging to the thruster of the aircraft, generally has a structure comprising an air intake upstream from the turbine engine, a middle section intended to surround a fan of the turbine engine, a downstream section harboring thrust reversal means and intended to surround the combustion chamber of the turbine engine, and is generally completed by an ejection nozzle, the outlet of which is located downstream from the turbine engine.
The air intake comprises an intake lip adapted so that the air required for feeding the fan and internal compressors of the turbine engine may be optimally collected to the turbine engine on the one hand, and a downstream structure on which the lip is added and intended to properly channel the air towards the vanes of the fan on the other hand.
This downstream structure notably comprises an internal ring-shaped wall 1, illustrated in FIGS. 1 and 2, and an external cowl (not shown) radially spaced apart from the internal wall 1.
The internal wall 1 of the air intake structure is extended with a fan case belonging to the middle section of the nacelle in a direction parallel to the longitudinal axis of the turbine engine.
More particularly, the downstream end of the internal wall 1 of the air intake and the upstream end of the case of the fan each bear peripheral connection flanges 2,3 for assembling together said air intake and fan case, by means of attachment elements such as screws 4 or bolts.
In present air intake structures, as illustrated in FIGS. 1 and 2, the connection flange 2 of the air intake structure is respectively attached downstream from the acoustic panel of the internal wall 1 or on the acoustic panel itself by bolted elements 5.
The presence of the bolted elements 5 then requires local reinforcements in the flange plane which have an incidence on the mass of the air intake structure.
Further, such arrangements limit the dimensions of the acoustic panel of the internal wall 1 of the air intake structure, if it is desired not to deteriorate it by the arrangement of the bolted elements 5, as illustrated in FIG. 1.
Air intake structures are also known, in which the internal wall and the corresponding flange for connection to the fan case are integrated into a single part in composite material.
Now, in such a part, interlaminar shearing is seen at the adhesively bonded link between the flange and the acoustic panel of the internal wall.
There then exists a risk of delamination in the composite part which causes a significant lowering of the mechanical strength of the internal wall of the air intake structure, and even breaking of the latter.


Degasifying apparatus is for eliminating gases, such as ambient air, from fluids, such as oil. The apparatus has at least one permeable membrane (26) that lets the gas to be eliminated from the fluid (22) penetrate through the permeable membrane and retains the liquid moiety of the fluid within the permeable membrane.

Air may be present in dissolved and in undissolved forms in pressure fluids such as hydraulic fluids. Although dissolved air is not visible in the fluid or oil, it is always present to a certain extent. Undissolved air is not always present in the fluid or oil, but when it is, it is visible as a second phase. Although the properties of pressure fluids, such as viscosity, compression modulus, and lubricating capacity, are substantially impaired by undissolved air, dissolved air also affects certain properties of the pressure fluid, for example ageing behavior and cavitation tendency.
The maximum amount of air that can be dissolved in the fluid concerned is determined by the saturation curve of the fluid concerned. However, in principle, solubility increases with increasing pressure and to a lesser extent is also dependent on temperature. Because pressures and temperatures in hydraulic systems vary over time, as well as according to location, a drop in pressure and consequent lowering of the solubility limit can result in air dissolving out during operation. As a result, the formation of a second phase (bubbles), and thus damage, for example by flow cavitation, can be expected, especially in areas of low static pressure, such as control cross sections of valves. Because the outgassing rate is greater than the dissolution rate, resulting air bubbles remain even when the pressure in the fluid increases again, thereby altering the properties of the pressure fluid on the one hand and possibly resulting in damages due to cavitation erosion upon a subsequent pressure increase on the other hand. In order to ensure reliable operation of hydraulic systems, it is necessary to take measures for degasifying the pressure fluid. Vacuum evaporation is the process currently employed for achieving a particularly effective degasification, in which the degassed fluid contains only a small residual contamination. Although this has the advantage that water is simultaneously eliminated, the very high energy requirement and the elaborate construction of the apparatus are disadvantageous. In addition there is usually an undesired heating of the fluid. Also, it is not possible to integrate the degasifying apparatus in a main fluid flow of the fluid system.


A ring clip for connecting two wire mesh panels. The clip has a first arm and a second arm. The arms connected at respective first ends by a hinge. A second end of the first arm defines a recess which is adapted to receive a second end of the second arm when the clip is in a closed condition. The first arm includes a first tab, and the second arm includes a second tab, such that, in the closed condition the first and second tabs are substantially opposed. The first and second tabs are substantially misaligned laterally.

It is known to place ground feeding birds in outdoor cages or runs so that they may safely feed within a bounded space during the day. Such cages are often made of a series of wire mesh panels. The mesh panels may be connected to a frame which defines the size of the cage. Alternatively, the mesh panels may be joined together by fastening arrangements in a self-supporting manner.
The number of birds kept may vary such that is necessary to increase or decrease the size of the cage. It may also be desirable to reconfigure the shape of the cage so that it may be fitted in a new location. Cages comprising mesh panels supported on a frame may not be reconfigured to alternate shapes to fit within new locations. Cages comprising mesh panels joined together by fastening arrangements require dedicated tools to dismount the fastening arrangements. The process of removing and reattaching the fasting arrangements is time consuming.


A mixer has its associated fuel gas nozzle inserted on one side and includes an inlet section for introducing combustion air via a gap defined therearound to allow it with a fuel and a jetting outlet section for jetting a resultant air/fuel mixture. A cylinder is fixed to the jetting outlet section to burn the mixture. A burner head is fixed to the cylinder to allow the mixture which is jetted from the jetting outlet section via diffusion holes to be guided into the cylinder.

1. Field of the Invention
The present invention relates to a burner for a combustion device which heats, for example, a refrigerant.
2. Description of the Related Art
A refrigerant heating device for heating, for example, a refrigerant is disclosed in Published Unexamined Japanese Patent Application 1-142371.
The refrigerant heating device includes a combustion device.
The combustion device comprises a mixer, bottom plate and burner.
The mixer has a fuel gas nozzle and primary air inlet on one end and an inner cylinder is provided in the mixer, allowing a fuel gas and primary air to be mixed in the mixer.
A jetting hole is provided in the bottom plate to jet a gas/air mixture into the burner from the inner cylinder.
A spark plug is provided in the burner to fire a mixture jetted from the jetting hole.
A flame outlet is provided on the outer periphery of the burner to guide secondary air. The secondary air is mixed with the mixture to provide an ideal combustion gas concentration so that it is fired.
A refrigerant tube is heated by heat of a hot combustion gas.
A burner for a combustion device in a water heater is disclosed, for example, in Published Unexamined Japanese Utility Model Application 63-109829.
The burner has a flame outlet for jetting a mixture of a gas fuel and primary air. The wall extends at a specific attitude from one side of the frame outlet so as to provide a firing zone.
A jetting outlet is provided in the wall to jet secondary combustion air.
A tube-like guide passage is defined for jetting a mixture with a cylindrical opening provided, as a flame outlet, at one end. The guide passage has its axis oriented at such an attitude as to conform to the direction in which the wall extends.
In either combustion device, the respective component parts are formed by bending or drawing a very thin metal plate.
The respective component parts are assembled as a cylinder or box whose width is very great compared to its height.
By so doing, it is possible to assemble a combustion device.
It is necessary to build up a rigid structure which is not readily broken due to some external shock.
For this reason, the conventional method was by assembling together respective associated component parts by an arc welding means.
The respective associated component parts are liable to be affected by heat involved and, even if being slightly heat-deformed, vary at their mounting position.
This causes a clearance or clearances to be produced between the component parts, resulting in a leakage of a fuel gas or primary air and in an unstable combustion.


Certain functionalized inosines, preferably C.sub.2 alkylated inosines, are prepared as new compounds having use as antiviral agents against viruses.

A number of viral induced diseases pose serious world-wide health problems for which effective chemotherapeutic agents must be developed. Although many chemotherapeutic agents are available clinically for the treatment of diseases caused by microorganisms (e.g. bacteria), the same cannot be said for viral diseases. At present, only a few effective antiviral nucleosides are known but most of these compounds are useful against only DNA viruses as opposed to RNA viruses.
The search for purine nucleosides with antiviral activity against RNA viruses requires a understanding of the many complex biological pathways involving purine metabolism in mammalian systems as well as some understanding of viral metabolism. It has now been found that strategically functionalized compounds related to natural inosine may be metabolically stable with respect to key mammalian enzymes of purine metabolism but may be phosphorylated by less specific RNA viral enzymes in viral infected cells and thus may inhibit viral replication.
The primary object of the present invention is to provide alkylated inosines, preferably C-2 alkylated inosines which have antiviral activity against certain RNA arboviruses.
Another object of the present invention is to provide a method for use of alkylated inosine derivatives as antiviral agents.
A yet further object of the present invention is to provide an effective and direct route of synthesis of alkylated inosines which allows those to be economically and conveniently available for use in therapeutic treatments against RNA viruses.
A still further objective is to provide therapeutic compositions useful as antivirals for RNA viruses.

2-substituted inosines and their use as antiviral agents


In downlink signal communication to a mobile terminal (200), the mobile terminal (200) is associated with a serving access node (100-1). Signal communication to a further mobile terminal (200; 200′″) may interfere with the signal communication between the serving access node (100-1) and the mobile terminal (200). In order to allow interference mitigation at the mobile terminal (200), the serving access node (100-1) obtains scheduling information pertaining to the signal communication to the further mobile terminal (200; 200′″). The obtained scheduling information is then forwarded to the mobile terminal (200) to be used for interference mitigation.

Cellular communication networks generally suffer from co-channel interference. That is to say, simultaneous transmissions using the same physical resources may generate mutual interference. Co-channel interference in turn reduces quality of received signals, which may be measured as Signal to Interference plus Noise Ratio (SINR), and therefore limits capacity.
In 3GPP LTE (3GPP: Third Generation Partnership Project, LTE: Long Term Evolution), it has been proposed to use a technique cooperation between cells, which is referred to as Coordinated Multi-Point Transmission and Reception (CoMP), for enhancing the SINR of a user equipment (UE) suffering from co-channel interference. Known strategies of using CoMP in DL signal communication are implemented at the access node in the communication network. One known strategy is to use coordinated scheduling. In coordinated scheduling, cooperating cells schedule their associated UEs in such a way that co-channel interference is avoided or reduced. However, as the used capacity of the cells increases, there is less freedom to accomplish coordinated scheduling. Another known strategy is to use joint transmission. In joint transmission, cooperating cells jointly send the same data to a UE. However, joint transmission may require significant bandwidth for exchanging the transmitted data between the cooperating cells.
Accordingly, there is a need for techniques that allow for efficient interference mitigation in DL signal communication.

Interference mitigation in downlink signal communication to a mobile terminal


An arthroscope cannula including inner and outer intimately engaged concentric tubes with the inner tube having a longitudinally extending wall depression defining, in conjunction with the outer tube, a pressure passage. The inner tube receives the scope which is restrained therein by the wall depression to define an inflow fluid passage. The outer tube is selectively removable from about the inner tube with both tubes mounting on and projecting from a flow controlling and directing bridge assembly.

The present invention is broadly concerned with cannula devices, and more particularly relates to cannula assemblies for use in arthroscopy or similar medical or surgical procedures wherein the sensing of pressure in the body joint or at the site of the procedure is a factor.
U.S. Pat. Nos. 4,650,462 and 4,820,265, are directed to equipment for use in arthroscopic procedures, which procedures are generally described in the patents. Such procedures have resulted in the development of number of special purpose cannulas for inflow and outflow of fluid, as well as for pressure sensing in the joint, including:
1. A dedicated pressure sensing cannula which is inserted into the joint in the manner of a large hypodermic needle, and connected to a pressure sensing line, as for example, noted in the tube set of U.S. Pat. No. 4,820,265. PA1 2. A dedicated outflow cannula comprising a tube between 3 mm and 6 mm in diameter which is inserted in the joint and connected to the outflow line. PA1 3. A combination inflow cannula consisting of concentric tubes with the inner tube approximately 3 mm and the outer tube approximately 4 mm in diameter. A small annulus is defined between the tubes which is used to sense the fluid pressure in the joint. The larger inside diameter of the inner tube carries the inflow from the input tube of the pump. PA1 4. A combination outflow cannula which is similar to the combination inflow cannula except that the inner tube carries the outflow from the joint while the annulus senses the pressure. PA1 1. Inflow through the arthroscope cannula, pressure sensing by a dedicated pressure sensing cannula, and outflow by a dedicated outflow cannula. PA1 2. Inflow and pressure sensing through a combination inflow cannula, and outflow through the arthroscope cannula. PA1 3. Inflow through the arthroscope cannula, and outflow and pressure sensing through a combination outflow cannula.
In an arthroscopic procedure, there is always at least one additional cannula involved, the arthroscope cannula in which the scope or viewing instrument is positioned. This cannula will normally incorporate means for fluid communication with the joint provided by the space defined between the outside diameter of the inserted arthroscope and the inside diameter of the arthroscope cannula tube.
From the above, it will be recognized that the doctor has many choices for setting up the joint for the arthroscopic procedure. Some of the most common are:
Methods 2 and 3 above are the ones most favored by doctors since only two incisions are required, as opposed to three incisions for method 1. A desirable alternative to methods 2 and 3, recognized in the development of the present invention, would be the incorporation of pressure sensing in an arthroscope cannula. Only two portals or incisions would be required, with inflow and pressure sensing in the arthroscope cannula, and outflow using a dedicated outflow cannula. This has a big safety advantage since both pressure sensing and inflow occur together. The same safety advantage is present in method 2 above, however, suction may be required to assist outflow.
An initial proposal was to use concentric tubes with an annular passage provided therebetween in the manner of the combination inflow and outflow cannulas. As far as the fluid control system was concerned, the cannula was acceptable. However, because of its manner of construction, with the spaced concentric tubes, a little over 1 millimeter was added to the diameter of the arthroscope cannula. This was considered undesirable and unacceptable to the doctors/users of the device. Thus the problem still remained as to how to provide for acceptable pressure sensing utilizing the arthroscope cannula.

Minnesota Mining and Manufacturing Company


A method of inerting pipelines, or buried tanks or wellbores consisting of preparing a composition including at least one superabsorbent (co)polymer partially or fully swollen in the presence of water, then injecting the composition directly into the pipelines or buried tank or well.

In many countries, the regulations oblige operators to inert unused pipelines as well as any buried tanks. The same applies to dry wells and abandoned wells used in drilling for oil or gas.
The operators of pipeline networks must employ the necessary means so that abandoned or unused pipelines and equipment cannot pose a safety hazards for persons and property.
The purpose of these regulatory requirements is to control the specific hazards that abandoned works may pose to persons or property, owing to:                the possibility of subsidence;        drainage to a building of any gas leak or any other fluids;        potential confusion between works when there are operations in the vicinity.
When a pipeline of the network is no longer to be used, the network operator is to adopt one of the following arrangements in the order of priority given below:                1) either use it as a sleeve for receiving another pipeline;        2) or abandon it temporarily with a view to later use as a sleeve;        3) or abandon it definitively in the ground. In this case the network operator must make arrangements intended to prevent any subsequent hazards of accident or land subsidence.
The arrangements to be made for eliminating these hazard are the inerting of pipelines.
"Inerting of abandoned pipelines, tanks or wells" means filling them with an inert substance for said abandoned pipelines, tanks or wells. In general, once filling has been carried out, the open ends are plugged to contain and protect the substance injected.
The pipelines may be:                gas pipes,        pipelines for water (in many cases such as irrigation, there is no such obligation).
Most often, the operators try to inert the pipelines temporarily and reuse them after variable time periods.
One solution for inerting pipelines consists of filling the pipeline with a slurry of sand. This technique is still difficult to apply because plugs form, preventing propagation of the sand. Moreover, if propagation is forced with high-pressure pumps, filling is incomplete. Finally, it is particularly difficult to unblock pipework with high-pressure pumps, as the pressure required may be greater than the strength of the pipes.
Another solution consists of injecting relatively homogeneous lean concrete using concrete pumps. However, such an operation is only possible over short distances, section by section, as the concrete pumps used for public works have limited pressures. Moreover, the use of high-pressure concrete pumps presents a risk of explosion of the pipelines, which condemns them definitively.
In the case of abandoning and of inerting pipelines in urban areas for example, the inerting operations are very expensive. In fact, to inject lean concrete, it is necessary to open up or drill the ground, roads or sidewalks every 100 or 200 meters. It is not in fact possible to push concrete beyond these distances. Moreover, the equipment for carrying out this drilling is bulky and expensive. Repairing road surfaces damaged during these operations is also expensive and causes a lot of inconvenience for traffic.
Regarding drilling for gas or oil, the regulations apply to dry wells or to abandoned wells.
Very often, dry wells are filled with sand or lean concrete, or partly sand with a concrete covering. For places with difficult access such as frozen lakes or offshore drilling, transport is particularly expensive, requiring the use of helicopters.
Finally, the tanks referred to in the invention are most often at old, disused service stations or are individual buried gas tanks.

Method of inerting pipelines, buried tanks or wellbores using an SAP