Patent application number | Description | Published |
20080308970 | PROCESS FOR MELTING SILICON POWDERS - A process for melting powders of a semiconductor material, such as silicon, to yield a high-purity solid product. The process generally entails introducing the powder into an elevated end of a tube inclined from horizontal and, while maintaining an inert atmosphere within the tube, rotating the tube so as to agitate and cause the powder therein to flow toward an oppositely-disposed lower end of the tube while heating the tube so that the powder melts as it flows toward the lower end of the tube. The molten material is then allowed to flow freely from the lower end of the tube and subsequently solidify to form a product. | 12-18-2008 |
20090031535 | SILICON RELEASE COATING, METHOD OF MAKING SAME, AND METHOD OF USING SAME - A method of making a release coating includes the following steps: forming a mixture that includes (a) solid components comprising (i) 20-99% silicon by weight and (ii) 1-80% silicon nitride by weight and (b) a solvent; applying the mixture to an inner portion of a crucible or graphite board adapted to form an ingot or wafer comprising silicon; and annealing the mixture in a nitrogen atmosphere at a temperature ranging from 1000 to 2000° C. The invention may also relate to release coatings and methods of making a silicon ingot or wafer including the use of a release coating. | 02-05-2009 |
20090194849 | METHODS AND APPARATUS FOR MANUFACTURING SEMICONDUCTOR WAFERS - Methods and apparatus for fabricating a semiconductor sheet are provided. In one aspect, a method for fabricating a semiconductor wafer includes applying a layer of semiconductor material across a portion of a setter material, introducing the setter material and the semiconductor material to a predetermined thermal gradient to form a melt, wherein the thermal gradient includes a predetermined nucleation and growth region, and forming at least one local cold spot in the nucleation and growth region to facilitate inducing crystal nucleation at the at least one desired location. | 08-06-2009 |
20090208770 | SEMICONDUCTOR SHEETS AND METHODS FOR FABRICATING THE SAME - A method of manufacturing a sheet of semiconductor material is provided. The method includes forming a first layer of silicon powder of at least one semiconductor material, wherein the first layer has a lower surface and an opposite upper surface. The method further includes depositing a second layer across the upper surface of the first layer, wherein the second layer of silicon powder has a melting point that is substantially similar to the melting point of the first layer of silicon powder. The method also includes heating at least one of the first and second layers of silicon powder to initiate a controlled melt of one of the first and second layer of silicon powder and to initiate crystallization of at least one of the first and second layers of silicon powder. | 08-20-2009 |
20090280336 | SEMICONDUCTOR SHEETS AND METHODS OF FABRICATING THE SAME - A method of fabricating a sheet of semiconductor material is provided. The method includes forming a first layer of silicon powder that has a lower surface and an opposite upper surface. The method also includes depositing a second layer of silicon powder across the upper surface of the first layer, wherein the second layer of silicon powder has a lower surface and an opposite upper surface and has a lower melting point than the first layer of silicon powder. The method also includes heating at least one of the first and second layers of silicon powder to initiate a controlled melt of at least one of the first and second layers of silicon powder, and cooling at least one of the first and second layers of silicon powder to initiate crystallization of at least one of the first and second layers of silicon powder. | 11-12-2009 |
20100012468 | MATERIAL HANDLING SYSTEM AND METHOD - A material handling system for moving material from a storage device to a receiver comprises a counter rotating double screw feeder extending from the storage device to the receiver. The counter rotating double screw feeder comprises an outer screw feed member; an inner screw feed member; where the outer screw feed member being positioned in an outer screw feed member tube; and the inner screw feed member being positioned in an inner screw feed member tube. The material is feed from the storage device to the process tube via the outer screw feed member; the inner screw feed member removes gas and byproducts from the receiver. | 01-21-2010 |
20110247549 | METHODS AND APPARATI FOR MAKING THIN SEMICONDUCTOR BODIES FROM MOLTEN MATERIAL - A pressure differential is applied across a mold sheet and a semiconductor (e.g. silicon) wafer is formed thereon. Relaxation of the pressure differential allows release of the wafer. The mold sheet may be cooler than the melt. Heat is extracted almost exclusively through the thickness of the forming wafer. The liquid and solid interface is substantially parallel to the mold sheet. The temperature of the solidifying body is substantially uniform across its width, resulting in low stresses and dislocation density and higher crystallographic quality. The mold sheet must allow flow of gas through it. The melt can be introduced to the sheet by: full area contact with the top of a melt; traversing a partial area contact of melt with the mold sheet, whether horizontal or vertical, or in between; and by dipping the mold into a melt. The grain size can be controlled by many means. | 10-13-2011 |
20120067273 | METHODS FOR EFFICIENTLY MAKING THIN SEMICONDUCTOR BODIES FROM MOLTEN MATERIAL FOR SOLAR CELLS AND THE LIKE - A pressure differential is applied across a mold sheet and a semiconductor (e.g. silicon) wafer (e.g. for solar cell) is formed thereon. Relaxation of the pressure differential allows release of the wafer. The mold sheet may be cooler than the melt. Heat is extracted almost exclusively through the thickness of the forming wafer. The liquid and solid interface is substantially parallel to the mold sheet. The temperature of the solidifying body is substantially uniform across its width, resulting in low stresses and dislocation density and higher crystallographic quality. The mold sheet must allow flow of gas through it. The melt can be introduced to the sheet by: full area contact with the top of a melt; traversing a partial area contact of melt with the mold sheet, whether horizontal or vertical, or in between; and by dipping the mold into a melt. The grain size can be controlled by many means. | 03-22-2012 |
Patent application number | Description | Published |
20130036967 | SELECTED METHODS FOR EFFICIENTLY MAKING THIN SEMICONDUCTOR BODIES FROM MOLTEN MATERIAL FOR SOLAR CELLS AND THE LIKE - A pressure differential is applied across a mold sheet and a semiconductor (e.g. silicon) wafer (e.g. for solar cell) is formed thereon. Relaxation of the pressure differential allows release of the wafer. The mold sheet may be cooler than the melt. Heat is extracted almost exclusively through the thickness of the forming wafer. The liquid and solid interface is substantially parallel to the mold sheet. The temperature of the solidifying body is substantially uniform across its width, resulting in low stresses and dislocation density and higher crystallographic quality. The mold sheet must allow flow of gas through it. The melt can be introduced to the sheet by: full area contact with the top of a melt; traversing a partial area contact of melt with the mold sheet, whether horizontal or vertical, or in between; and by dipping the mold into a melt. The grain size can be controlled by many means. | 02-14-2013 |
20140113156 | MAKING SEMICONDUCTOR BODIES FROM MOLTEN MATERIAL USING A FREE-STANDING INTERPOSER SHEET - An interposer sheet can be used for making semiconductor bodies, such as of silicon, such as for solar cell use. It is free-standing, very thin, flexible, porous and able to withstand the chemical and thermal environment of molten semiconductor without degradation. It is typically of a ceramic material, such as silica, silicon nitride, silicon oxynitride, silicon oxycarbide, silicon carbide, silicon carbonitride, silicon oxycarbonitride and others. It is provided between a forming surface of a mold sheet, and the molten material from which a semiconductor body will be formed. It may be secured to the forming surface or deposited upon the melt. The interposer sheet suppresses grain nucleation, and limits heat flow from the melt. It promotes separation of the semiconductor body from the forming surface. It can be fabricated before its use. Because free-standing and not adhered to the forming surface, problems of mismatch of CTE are minimized. The interposer sheet and semiconductor body are free to expand and contract relatively independently of the forming surface. | 04-24-2014 |
20140220171 | APPARATI FOR FABRICATING THIN SEMICONDUCTOR BODIES FROM MOLTEN MATERIAL - A pressure differential can be applied across a mold sheet and a semiconductor (e.g. silicon) wafer (e.g. for solar cell) is formed thereon. Relaxation of the pressure differential can allow release of the wafer. The mold sheet may be cooler than the melt. Heat is extracted through the thickness of the forming wafer. The temperature of the solidifying body is substantially uniform across its width, resulting in low stresses and dislocation density and higher crystallographic quality. The mold sheet can allow flow of gas through it. The melt can be introduced to the sheet by: full area contact with the top of a melt; traversing a partial area contact of melt with the mold sheet, whether horizontal or vertical, or in between; and by dipping the mold into a melt. The grain size can be controlled by many means. | 08-07-2014 |