Abstract: A system for processing substrates has a vacuum enclosure and a processing chamber situated to process wafers in a processing zone inside the vacuum enclosure. Two rail assemblies are provided, one on each side of the processing zone. Two chuck arrays ride, each on one of the rail assemblies, such that each is cantilevered on one rail assemblies and support a plurality of chucks. The rail assemblies are coupled to an elevation mechanism that places the rails in upper position for processing and at lower position for returning the chuck assemblies for loading new wafers. A pickup head assembly loads wafers from a conveyor onto the chuck assemblies. The pickup head has plurality of electrostatic chucks that pick up the wafers from the front side of the wafers. Cooling channels in the processing chucks are used to create air cushion to assist in aligning the wafers when delivered by the pickup head.

Abstract: A photovoltaic cell having a graded doped region such as a graded emitter and methods of making photovoltaic cells having graded doped regions such as a graded emitter are disclosed. Doping is adjusted across a surface to minimize resistive (I2R) power losses. The graded emitters provide a gradual change in sheet resistance over the entire distance between the lines. The graded emitter profile may have a lower sheet resistance near the metal lines and a higher sheet resistance farther from the metal line edges. The sheet resistance is graded such that the sheet resistance is lower where I2R power losses are highest due to current crowding. One advantage of graded emitters over selective emitters is improved efficiency. An additional advantage of graded emitters over selective emitters is improved ease of aligning metallization to the low sheet resistance regions.

Abstract: A system for processing substrates has a vacuum enclosure and a processing chamber situated to process wafers in a processing zone inside the vacuum enclosure. Two rail assemblies are provided, one on each side of the processing zone. Two chuck arrays ride, each on one of the rail assemblies, such that each is cantilevered on one rail assemblies and support a plurality of chucks. The rail assemblies are coupled to an elevation mechanism that places the rails in upper position for processing and at lower position for returning the chuck assemblies for loading new wafers. A pickup head assembly loads wafers from a conveyor onto the chuck assemblies. The pickup head has plurality of electrostatic chucks that pick up the wafers from the front side of the wafers. Cooling channels in the processing chucks are used to create air cushion to assist in aligning the wafers when delivered by the pickup head.

Abstract: Photovoltaic modules comprise solar cells having doped domains of opposite polarities along the rear side of the cells. The doped domains can be located within openings through a dielectric passivation layer. In some embodiments, the solar cells are formed from thin silicon foils. Doped domains can be formed by printing inks along the rear surface of the semiconducting sheets. The dopant inks can comprise nanoparticles having the desired dopant.

Abstract: A system for processing substrates has a vacuum enclosure and a processing chamber situated to process wafers in a processing zone inside the vacuum enclosure. Two rail assemblies are provided, one on each side of the processing zone. Two chuck arrays ride, each on one of the rail assemblies, such that each is cantilevered on one rail assemblies and support a plurality of chucks. The rail assemblies are coupled to an elevation mechanism that places the rails in upper position for processing and at lower position for returning the chuck assemblies for loading new wafers. A pickup head assembly loads wafers from a conveyor onto the chuck assemblies. The pickup head has plurality of electrostatic chucks that pick up the wafers from the front side of the wafers. Cooling channels in the processing chucks are used to create air cushion to assist in aligning the wafers when delivered by the pickup head.

Abstract: Photovoltaic modules comprise solar cells having doped domains of opposite polarities along the rear side of the cells. The doped domains can be located within openings through a dielectric passivation layer. In some embodiments, the solar cells are formed from thin silicon foils. Doped domains can be formed by printing inks along the rear surface of the semiconducting sheets. The dopant inks can comprise nanoparticles having the desired dopant.

Abstract: A photovoltaic cell having a graded doped region such as a graded emitter and methods of making photovoltaic cells having graded doped regions such as a graded emitter are disclosed. Doping is adjusted across a surface to minimize resistive (I2R) power losses. The graded emitters provide a gradual change in sheet resistance over the entire distance between the lines. The graded emitter profile may have a lower sheet resistance near the metal lines and a higher sheet resistance farther from the metal line edges. The sheet resistance is graded such that the sheet resistance is lower where I2R power losses are highest due to current crowding. One advantage of graded emitters over selective emitters is improved efficiency. An additional advantage of graded emitters over selective emitters is improved ease of aligning metallization to the low sheet resistance regions.

Abstract: Highly uniform silicon/germanium nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silicon/germanium particles can be surface modified to form the dispersions. The silicon/germanium nanoparticles can be doped to change the particle properties. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to form selectively doped deposits of semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: Laser based processes are used alone or in combination to effectively process doped domains for semiconductors and/or current harvesting structures. For example, dopants can be driven into a silicon/germanium semiconductor layer from a bare silicon/germanium surface using a laser beam. Deep contacts have been found to be effective for producing efficient solar cells. Dielectric layers can be effectively patterned to provide for selected contact between the current collectors and the doped domains along the semiconductor surface. Rapid processing approaches are suitable for efficient production processes.

Abstract: In order to better and more efficiently assemble back contact solar cells into modules, the cell to cell soldering and other soldered connections are replaced by electro and/or electroless plating. Back contact solar cells, diodes and external leads can be first laminated to the module front glass for support and stability. Conductive materials are deposited selectively to create a plating seed pattern for the entire module circuit. Subsequent plating steps create an integrated cell and module metallization. This avoids stringing and tabbing and the associated soldering steps. This process is easier for mass manufacturing and is advantageous for handling fragile silicon solar cells. Additionally, since highly corrosion resistant metals can be plated, the moisture barrier requirements of the back side materials can be greatly relaxed. This can simplify and reduce the cost of the back side of the module.

Abstract: Highly uniform silicon/germanium nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silicon/germanium particles can be surface modified to form the dispersions. The silicon/germanium nanoparticles can be doped to change the particle properties. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to form selectively doped deposits of semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: Photovoltaic modules comprise solar cells having doped domains of opposite polarities along the rear side of the cells. The doped domains can be located within openings through a dielectric passivation layer. In some embodiments, the solar cells are formed from thin silicon foils. Doped domains can be formed by printing inks along the rear surface of the semiconducting sheets. The dopant inks can comprise nanoparticles having the desired dopant.

Abstract: Highly uniform silica nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silica particles can be surface modified to form the dispersions. The silica nanoparticles can be doped to change the particle properties and/or to provide dopant for subsequent transfer to other materials. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to selectively dope semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: Highly uniform silica nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silica particles can be surface modified to form the dispersions. The silica nanoparticles can be doped to change the particle properties and/or to provide dopant for subsequent transfer to other materials. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to selectively dope semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: Photovoltaic modules comprise solar cells having doped domains of opposite polarities along the rear side of the cells. The doped domains can be located within openings through a dielectric passivation layer. In some embodiments, the solar cells are formed from thin silicon foils. Doped domains can be formed by printing inks along the rear surface of the semiconducting sheets. The dopant inks can comprise nanoparticles having the desired dopant.

Abstract: Highly uniform silica nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silican particles can be surface modified to form the dispersions. The silica nanoparticles can be doped to change the particle properties and/or to provide dopant for subsequent transfer to other materials. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to selectively dope semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: A photovoltaic module having non-contacting bus bars and methods of making non-contacting bus bars are disclosed. The fingers are screen printed on the substrate using a paste. The bus bar(s) can be formed over the fingers using a number of techniques that do not dissolve through the passivation layer of the substrate. The bus bar(s) can be screen printed over the fingers using a second paste that is more viscous and/or conductive than the first paste. The bus bar(s) can be a conductive trace that is deposited over the fingers. The bus bar(s) can be a metal wire coated with solder or paste that is positioned on the fingers. Metal plating techniques may also be used to thicken the fingers and/or bus bars. One or more doping steps may be used to form selective emitters under the fingers and bus bar.

Abstract: Highly uniform silica nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silican particles can be surface modified to form the dispersions. The silica nanoparticles can be doped to change the particle properties and/or to provide dopant for subsequent transfer to other materials. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to selectively dope semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: Highly uniform silica nanoparticles can be formed into stable dispersions with a desirable small secondary particle size. The silican particles can be surface modified to form the dispersions. The silica nanoparticles can be doped to change the particle properties and/or to provide dopant for subsequent transfer to other materials. The dispersions can be printed as an ink for appropriate applications. The dispersions can be used to selectively dope semiconductor materials such as for the formation of photovoltaic cells or for the formation of printed electronic circuits.

Abstract: A method of fabricating a solar cell comprising: providing a semiconducting wafer having a front surface, a back surface, and a background doped region; performing a set of ion implantations of dopant into the semiconducting wafer to form a back alternatingly-doped region extending from the back surface of the semiconducting wafer to a location between the back surface and the front surface, wherein the back doped region comprises laterally alternating first back doped regions and second back doped regions, and wherein the first back doped regions comprise a different charge type than the second back doped regions and the background doped region; and disposing a back metal contact layer onto the back surface of the semiconducting wafer, wherein the back metal contact layer is aligned over the first and second back doped regions and is configured to conduct electrical charge from the first and second back doped regions.