Methods for forming optoelectronic devices including heterojunction

A method for forming an optoelectronic semiconductor device, the method comprising:nforming an intermediate layer on an absorber layer, wherein the absorber layer is made of gallium arsenide (GaAs) and has only one type of doping, the intermediate layer having the same type of doping as the absorber layer; andforming an emitter layer on the intermediate layer, wherein the emitter layer is located closer than the absorber layer to a back side of the device, the emitter layer being made of a different material than the absorber layer and having a higher bandgap than the absorber layer, wherein the intermediate layer includes the different material of the emitter layer,wherein a heterojunction is formed between the emitter layer and the absorber layer, and wherein a p-n junction is formed between the emitter layer and the absorber layer at a location offset from the heterojunction, the p-n junction causing a voltage to be generated in the device in response to the device being exposed to light.

A method for forming a solar cell, the method comprising:nforming an absorber layer made of gallium arsenide (GaAs) and having only one type of doping;forming an emitter layer made of a different material than the absorber layer and having a higher bandgap than the absorber layer; andforming an intermediate layer between the absorber layer and the emitter layer, the intermediate layer having the same type of doping as the absorber layer, wherein the intermediate layer includes a material gradation from GaAs at a side closer to the absorber layer, to the different material of the emitter layer at a side closer to the emitter layer,wherein a heterojunction is formed between the emitter layer and the absorber layer, and wherein a p-n junction is formed between the emitter layer and the absorber layer and at least partially within the different material at a location offset from the heterojunction, the p-n junction causing a voltage to be generated in the cell in response to the cell being exposed to light at a front side of the cell.

A method for forming a photovoltaic cell, the method comprising:nforming an absorber layer made of gallium arsenide (GaAs) and having only one type of doping;forming an emitter layer made of a different material than the absorber layer and having a higher bandgap than the absorber layer;forming an intermediate layer between the absorber layer and the emitter layer, the intermediate layer having the same type of doping as the absorber layer; andsuch that a heterojunction is formed between the emitter layer and the absorber layer and a p-n junction formed between the emitter layer and the absorber layer and at least partially within the different material at a location offset from the heterojunction, wherein a majority of the absorber layer is outside of a depletion region formed by the p-n junction, the p-n junction causing a voltage to be generated in the cell in response to the cell being exposed to light at a front side of the cell.