Abstract: A method for an improved doping process allows for improved control of doping concentrations on a substrate. The method may comprise printing a polymeric material on a substrate in a desired pattern; and depositing a barrier layer on the substrate with a liquid phase deposition process, wherein a pattern of the barrier layer is defined by the polymeric material. The method further comprises removing the polymeric material, and doping the substrate. The barrier layer substantially prevents or reduces doping of the substrate to allow patterned doping regions to be formed on the substrate. The method can be repeated to allow additional doping regions to be formed on the substrate.

Abstract: In some cases, it is desirable to perform doping when manufacturing a solar cell to improve efficiency. Dopant diffusion may include the steps of: (a) an initial temperature ramp, (b) dopant vapor flow, (c) drive-in, and (d) cool down. However, doping may result in excessive doping, such as in regions where the solar cell has been nanoscale textured to provide black silicon, thereby creating a dead zone with excessive recombination of charge carriers. In the systems and method discussed herein, dopant vapor flow and drive-in steps may be performed at two different temperature set points to minimize or eliminate the formation of dead zones. In some embodiments, the dopant vapor flow may be performed at a lower temperature set point than the drive-in.

Abstract: Systems and methods for etching the surface of a substrate may utilize a thin layer of fluid to etch a substrate for improved anti-reflective properties. The substrate may be secured with a holding fixture that is capable of positioning the substrate. A fluid comprising an acid and an oxidizer for etching may be prepared, which may optionally include a metal catalyst. An amount of fluid necessary to form a thin layer contacting the surface of the substrate to be etched may be dispensed. The fluid may be spread into the thin layer utilizing a tray that the substrate is dipped into, a plate that is placed near the surface of the substrate to be etched, or a spray or coating device.

Abstract: Systems and methods for producing nanoscale textured low reflectivity surfaces may be utilized to fabricate solar cells. A substrate may be patterned with a resist prior to an etching process that produces a nanoscale texture on the surface of the substrate. Additionally, the substrate may be subjected to a dopant diffusion process. Prior to dopant diffusion, the substrate may be optionally subjected to liquid phase deposition to deposit a material that allows for patterned doping. The order of the nanoscale texture etching and dopant diffusion may be modified as desired to produce post-nano emitters or pre-nano emitters.

Abstract: In some cases, it is desirable to perform doping when manufacturing a solar cell to improve efficiency. Dopant diffusion may include the steps of: (a) an initial temperature ramp, (b) dopant vapor flow, (c) drive-in, and (d) cool down. However, doping may result in excessive doping, such as in regions where the solar cell has been nanoscale textured to provide black silicon, thereby creating a dead zone with excessive recombination of charge carriers. In the systems and method discussed herein, dopant vapor flow and drive-in steps may be performed at two different temperature set points to minimize or eliminate the formation of dead zones. In some embodiments, the dopant vapor flow may be performed at a lower temperature set point than the drive-in.

Abstract: Systems and methods for etching the surface of a substrate may utilize a thin layer of fluid to etch a substrate for improved anti-reflective properties. The substrate may be secured with a holding fixture that is capable of positioning the substrate. A fluid comprising an acid and an oxidizer for etching may be prepared, which may optionally include a metal catalyst. An amount of fluid necessary to form a thin layer contacting the surface of the substrate to be etched may be dispensed. The fluid may be spread into the thin layer utilizing a tray that the substrate is dipped into, a plate that is placed near the surface of the substrate to be etched, or a spray or coating device.

Abstract: A method for an improved doping process allows for improved control of doping concentrations on a substrate. The method may comprise printing a polymeric material on a substrate in a desired pattern; and depositing a barrier layer on the substrate with a liquid phase deposition process, wherein a pattern of the barrier layer is defined by the polymeric material. The method further comprises removing the polymeric material, and doping the substrate. The barrier layer substantially prevents or reduces doping of the substrate to allow patterned doping regions to be formed on the substrate. The method can be repeated to allow additional doping regions to be formed on the substrate.

Abstract: Systems and methods for producing nanoscale textured low reflectivity surfaces may be utilized to fabricate solar cells. A substrate may be patterned with a resist prior to an etching process that produces a nanoscale texture on the surface of the substrate. Additionally, the substrate may be subjected to a dopant diffusion process. Prior to dopant diffusion, the substrate may be optionally subjected to liquid phase deposition to deposit a material that allows for patterned doping. The order of the nanoscale texture etching and dopant diffusion may be modified as desired to produce post-nano emitters or pre-nano emitters.

Abstract: This invention relates to electrophotographic elements containing a layer formed from coating compositions containing a mixture of polymeric binders, including a polyvinyl butyral and a polyester ionomer and a crystalline mixture of unsubstituted titanyl phthalocyanine pigment, titanyl phthalocyanine pigments or mixtures thereof dispersed in the mixture. More particularly the invention relates to electrophotographic elements containing photoconductive layers which are especially useful for forming a photoconductive layer that is very uniform and highly absorptive at relatively thin coverage with good inter layer adhesion. The electrophotographic elements produced using this coating composition are particularly suited for high quality applications such as providing copy images with very low grain.

Abstract: An amorphous mixture consisting essentially of TiOFPc and TiOPc and containing more than 75 weight percent of substantially chlorine-free TiOPc is produced by forming a mixture of crude crystalline TiOFPc and crude crystalline, substantially chlorine-free TiOPc that contains less than 80 weight percent TiOPc, treating the mixture under conditions effective to form a substantially amorphous mixture of TiOFPc and TiOPc containing less than 75 weight percent TiOPc, which is then treated with water, and dried. A further amount of crude crystalline, substantially chlorine-free TiOPc sufficient to form a new mixture containing more than 75 weight percent of substantially chlorine-free TiOPc is added, and the new mixture is converted to a substantially amorphous mixture of TiOFPc and TiOPc. A nanoparticulate cocrystalline composition is obtained by forming a slurry in an organic solvent of the dried substantially amorphous mixture, and wet milling the slurry to form the cocrystalline composition.

Abstract: In a process for forming an amorphous TiOPc/TiOFPc pigment mixture containing a low concentration of TiOFPc, a mixture containing phthalonitrile and titanium tetrachloride is subjected to reaction conditions effective to form lightly chlorine-substituted crude crystalline Cl—TiOPc. The lightly chlorine-substituted crude crystalline Cl—TiOPc is combined with crude crystalline TiOFPc in a weight ratio from about 75:25 Cl—TiOPc:TiOFPc to about 99.5:0.5 Cl—TiOPc:TiOFPC to form a crude crystalline pigment mixture, which is treated under conditions effective to form a substantially amorphous pigment mixture of Cl—TiOPc and TiOFPc. The substantially amorphous mixture can subsequently be converted to a nanocrystalline Cl—TiOPc/TiOFPc pigment composition containing a low concentration of TiOFPc.

Abstract: This invention relates to electrophotographic elements containing a layer formed from coating compositions containing a mixture of polymeric binders, including a polyvinyl butyral and a polyester ionomer and a crystalline mixture of unsubstituted titanyl phthalocyanine pigment, titanyl phthalocyanine pigments or mixtures thereof dispersed in the mixture. More particularly the invention relates to electrophotographic elements containing photoconductive layers which are especially useful for forming a photoconductive layer that is very uniform and highly absorptive at relatively thin coverage with good inter layer adhesion. The electrophotographic elements produced using this coating composition are particularly suited for high quality applications such as providing copy images with very low grain.

Abstract: In a process for forming an amorphous TiOPc/TiOFPc pigment mixture containing a low concentration of TiOFPc, a mixture containing phthalonitrile and titanium tetrachloride is subjected to reaction conditions effective to form lightly chlorine-substituted crude crystalline Cl—TiOPc. The lightly chlorine-substituted crude crystalline Cl—TiOPc is combined with crude crystalline TiOFPc in a weight ratio from about 75:25 Cl—TiOPc:TiOFPc to about 99.5:0.5 Cl—TiOPc:TiOFPC to form a crude crystalline pigment mixture, which is treated under conditions effective to form a substantially amorphous pigment mixture of Cl—TiOPc and TiOFPc. The substantially amorphous mixture can subsequently be converted to a nanocrystalline Cl—TiOPc/TiOFPc pigment composition containing a low concentration of TiOFPc.

Abstract: An amorphous mixture consisting essentially of TiOFPc and TiOPc and containing more than 75 weight percent of substantially chlorine-free TiOPc is produced by forming a mixture of crude crystalline TiOFPc and crude crystalline, substantially chlorine-free TiOPc that contains less than 80 weight percent TiOPc, treating the mixture under conditions effective to form a substantially amorphous mixture of TiOFPc and TiOPc containing less than 75 weight percent TiOPc, which is then treated with water, and dried. A further amount of crude crystalline, substantially chlorine-free TiOPc sufficient to form a new mixture containing more than 75 weight percent of substantially chlorine-free TiOPc is added, and the new mixture is converted to a substantially amorphous mixture of TiOFPc and TiOPc. A nanoparticulate cocrystalline composition is obtained by forming a slurry in an organic solvent of the dried substantially amorphous mixture, and wet milling the slurry to form the cocrystalline composition.