摘要:
An apparatus and method for fabricating a mount for an aluminum nitride (AlN) seed for single crystal aluminum nitride growth is provided. A holder having a proximal base and wall portions extending therefrom is fabricated from crystal growth crucible material, and defines an internal cavity. An AlN seed is placed within the holder, and placed within a nitrogen atmosphere at a temperature at or exceeding the melting point of a suitable material capable of forming a nitride ceramic by nitridation, such as aluminum. Pellets fabricated from this material are dropped into the holder and onto the seed, so that they melt and react with the nitrogen atmosphere to form a nitride ceramic. The seed is effectively molded in-situ with the ceramic, so that the ceramic and holder forms a closely conforming holder for the seed, suitable for single crystal AlN growth.
摘要:
According to one aspect of the invention, an improved process for preparing a surface of substrate is provided wherein the surface of the substrate is prepared for a chemical mechanical polishing (CMP) process, the CMP process is performed on the surface of the substrate, and the surface of the substrate is finished to clear the substrate surface of any active ingredients from the CMP process. Also, an improved substrate produced by the method is provided. According to one aspect of the invention, particular polishing materials and procedures may be used that allow for increased quality of AlN substrate surfaces.
摘要:
According to one aspect of the invention, an improved process for preparing a surface of substrate is provided wherein the surface of the substrate is prepared for a chemical mechanical polishing (CMP) process, the CMP process is performed on the surface of the substrate, and the surface of the substrate is finished to clear the substrate surface of any active ingredients from the CMP process. Also, an improved substrate produced by the method is provided. According to one aspect of the invention, particular polishing materials and procedures may be used that allow for increased quality of AlN substrate surfaces.
摘要:
A method of manufacturing a transparent oxide layer is provided. The manufacturing method includes disposing a cadmium tin oxide layer on a support, placing the support with the cadmium tin oxide layer within a chamber of a rapid thermal annealing system, and rapidly thermally annealing the cadmium tin oxide layer by exposing the cadmium tin oxide layer to electromagnetic radiation to form the transparent oxide layer, wherein the rapid thermal anneal is performed without first pumping down the chamber.
摘要:
Bulk single crystals of AlN having a diameter greater than about 25 mm and dislocation densities of about 10,000 cm−2 or less and high-quality AlN substrates having surfaces of any desired crystallographic orientation fabricated from these bulk crystals.
摘要:
In one aspect of the present invention, a method is provided. The method includes disposing a substantially amorphous cadmium tin oxide layer on a support; and thermally processing the substantially amorphous cadmium tin oxide layer in an atmosphere substantially free of cadmium from an external source to form a transparent layer, wherein the transparent layer has an electrical resistivity less than about 2×10−4 Ohm-cm. Method of making a photovoltaic device is also provided.
摘要:
Systems and methods for crystal growth are provided. One method includes producing a lateral thermal profile in a furnace having a crucible therein containing a material for growing a crystal. The lateral thermal profile has three zones, wherein the first and third zones have temperatures above and below a melting point of the material, respectively, and the second zone has a plurality of temperatures with at least one temperature equal to the melting point of the material. The method further includes combining the lateral thermal profile with a vertical thermal gradient produced in the furnace, wherein the vertical thermal gradient causes a point in a bottom of the crucible located in the third zone to be the coldest point in the crucible. The method also includes transferring heat from the first and second zones to the third zone to produce a leading edge of the interface.
摘要:
A method for forming a back contact for a photovoltaic cell that includes at least one semiconductor layer is provided. The method includes applying a continuous film of a chemically active material on a surface of the semiconductor layer and activating the chemically active material such that the activated material etches the surface of the semiconductor layer. The method further includes removing the continuous film of the activated material from the photovoltaic cell and depositing a metal contact layer on the etched surface of the semiconductor layer.
摘要:
Systems and methods for crystal growth are provided. One method includes producing a lateral thermal profile in a furnace having a crucible therein containing a material for growing a crystal. The lateral thermal profile has three zones, wherein the first and third zones have temperatures above and below a melting point of the material, respectively, and the second zone has a plurality of temperatures with at least one temperature equal to the melting point of the material. The method further includes combining the lateral thermal profile with a vertical thermal gradient produced in the furnace, wherein the vertical thermal gradient causes a point in a bottom of the crucible located in the third zone to be the coldest point in the crucible. The method also includes transferring heat from the first and second zones to the third zone to produce a leading edge of the interface.
摘要:
Methods are provided for forming a back contact for a photovoltaic cell that includes at least one semiconductor layer. One method includes depositing at least one back contact material on a metal contact. The back contact material comprises a metal nitride or a metal phosphide. The method further includes depositing an absorber layer comprising cadmium and tellurium above the back contact material and thermally processing the back contact material, such that the back contact material interacts with the absorber layer to form an interlayer that lowers a contact resistance for the photovoltaic cell. A photovoltaic cell is also provided and includes comprising a metal contact, at least one back contact material disposed on the metal contact, and an absorber layer comprising a material comprising cadmium and tellurium disposed above the back contact material. An interlayer is disposed between the back contact material and the absorber layer and comprises a compositionally graded layer of the back contact material and the absorber layer material. The photovoltaic cell further includes a window layer disposed above the absorber layer.