The Polycrystalline-Si Contact to GaAs
Abstract
Polycrystalline Si/GaAs interfaces have been formed by depositing hydrogenated amorphous Si (a-Si:H) onto GaAs in a silane plasma at 450 C, followed by anneals up to 1050 C. Analysis by Rutherford backscattering, secondary ion mass spectroscopy, and TEM indicate that the resulting undoped polycrystalline Si/GaAs interface is metallurgically stable, while significant interdiffusion occurs upon addition of P or As to the Si. The magnitude of the diffusion, 10 to the -11 sq cm/s at 1000 C, increases with P concentration, and may also depend on the As concentration. Good agreement is found between diffusion profiles and the Greiner/Gibbons (1984) theory. Ohmic contacts prepared using Si(P-4a/o)/GaAs gave contact resistances as low as 1.4 x 10 to the -4th ohm sq cm.
- Publication:
-
Journal of the Electrochemical Society
- Pub Date:
- June 1986
- DOI:
- 10.1149/1.2108814
- Bibcode:
- 1986JElS..133.1176K
- Keywords:
-
- Contact Resistance;
- Electric Contacts;
- Gallium Arsenides;
- Polycrystals;
- Silicon Films;
- Additives;
- Annealing;
- Arsenic;
- Heat Treatment;
- Phosphorus;
- Solid-State Physics