Patent ID: 11875907
Assignee: CITY LABS, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC G  H | IPC G  H

Claim 13:
14. A device for producing electricity, comprising:
in a first stacked configuration:
a first conductive contact layer;
a first doped GaAs substrate layer;
a first back-surface field layer overlying the first doped GaAs substrate layer;
a first InGaP base layer overlying at least a portion of the first back-surface field layer and doped with a p-type dopant;
a first InGaP emitter layer overlying the first InGaP base layer and doped with an n-type dopant;
a first window layer overlying the first InGaP emitter layer;
a first cap layer overlying the first window layer;
a first radioisotope source proximate or in contact with the first cap layer;

a first contact in electrical contact with the first back-surface field layer or with the first base layer;
a second contact in electrical contact with the first cap layer or in electrical contact with first window layer or in contact with the first emitter layer;
in a second stacked configuration:
a second conductive contact layer;
a second doped GaAs substrate layer;
a second back-surface field layer overlying the second doped GaAs substrate layer;
a second InGaP base layer overlying the second back-surface field layer and doped with p-type dopant;
a second InGaP emitter layer overlying the second InGaP base layer and doped with n-type dopant;
a second window layer overlying the second InGaP emitter layer;
a second cap layer overlying at least a portion of the second window layer;
a second radioisotope source proximate or in contact with the second cap layer;

a third contact in electrical contact with the second back-surface field layer or with the second base layer;
a fourth contact in electrical contact with the second cap layer or in electrical contact with second window layer or in contact with second emitter layer;
wherein, the first conductive contact layer is disposed in electrical contact with the second conductive contact layer;
and wherein current is supplied to a load connected between the first and third contacts or between the second and fourth contacts.