US 12,490,493 B2
Semiconductor devices with a compositionally graded layer, and methods of making and use thereof
Siddharth Rajan, Columbus, OH (US); and Sushovan Dhara, Columbus, OH (US)
Assigned to Ohio State Innovation Foundation, Columbus, OH (US)
Filed by Ohio State Innovation Foundation, Columbus, OH (US)
Filed on May 4, 2023, as Appl. No. 18/143,191.
Claims priority of provisional application 63/358,288, filed on Jul. 5, 2022.
Prior Publication US 2024/0014285 A1, Jan. 11, 2024
Int. Cl. H10D 64/64 (2025.01); H10D 62/80 (2025.01); H10D 64/62 (2025.01)
CPC H10D 64/64 (2025.01) [H10D 62/80 (2025.01); H10D 64/62 (2025.01)] 19 Claims
OG exemplary drawing
 
1. A device comprising:
a first electrode layer;
a first semiconductor layer comprising a first semiconductor material having a first bandgap;
a second semiconductor layer having a top surface, a bottom surface, and a thickness, the thickness being the average dimension from the top surface to the bottom surface;
wherein the second semiconductor layer comprises a second semiconductor material that varies across the thickness from the bottom surface to the top surface, such that the second semiconductor material has a compositional gradient with thickness from an initial composition having an initial band gap at the bottom surface to a final comparison having a final bandgap at the top surface, such that the second semiconductor layer has a bandgap that varies with thickness from an initial bandgap at the bottom surface to a final bandgap at the top surface, wherein the final bandgap is greater than the initial bandgap, and the final bandgap is greater than the first bandgap;
an optional dielectric layer; and
a second electrode layer;
wherein the first semiconductor layer is disposed on top of and in physical contact with the first electrode layer;
wherein the second semiconductor layer is disposed on top of and in physical contact with the first semiconductor layer, such that bottom surface of the second semiconductor layer is disposed on and in physical contact with the first semiconductor layer and the first semiconductor layer is disposed between and in physical contact with the first electrode layer and bottom surface of the second semiconductor layer;
when the optional dielectric layer is present, then:
the optional dielectric layer is disposed on top of an in physical contact with the second semiconductor layer, such that the second semiconductor layer is disposed between and in physical contact with the first electrode layer and the optional dielectric layer, the top surface of the second semiconductor layer being in physical contact with the optional dielectric layer and the bottom surface of the second semiconductor layer being in physical contact with the first semiconductor layer; and
the second electrode layer is disposed on top of and in physical contact with the optional dielectric layer, such that the optional dielectric layer is disposed between and in physical contact with the second electrode layer and the second semiconductor layer; and
when the optional dielectric layer is absent, then:
the second electrode layer is disposed on top of an in physical contact with the second semiconductor layer, such that the second semiconductor layer is disposed between and in physical contact with the second electrode layer and the first semiconductor layer, the top surface of the second semiconductor layer being in physical contact with the second electrode layer and the bottom surface of the second semiconductor layer being in physical contact with the first semiconductor layer.