Sandip Tiwari, Steven L. Wright, et al.
IEEE Electron Device Letters
We describe the use of a p-type refractory ohmic contact in ohmic self-aligned devices. The contacts are based on self-aligned diffusion of zinc-doped tungsten film. The diffusion is nearly isotropic in the vicinity of silicon nitride sidewalls, allowing self-alignment of ohmic contacts with emitters and gates. Lowresistance contacts (< 10-6 Ω. cm2) are formed both to GaAs and GaAIAs, and the lifetime of the diffused region is superior to that obtained from implantation. Heterostructure bipolar transistors (HBT's) showing high current gains (≥50 at 2 x 103 A.cm-2 and ≥200 at 1 x 105 A.cm-2 with micrometer-sized emitter widths) and p-channel GaAs gate heterostructure field-effect transistors (HFET's) showing high transconductances (78 mS/mm at 2.2-μm gate length) have been fabricated using this contact. © 1988 IEEE.
Sandip Tiwari, Steven L. Wright, et al.
IEEE Electron Device Letters
Farhan Rana, Sandip Tiwari, et al.
Applied Physics Letters
Hao Lin, Haitao Liu, et al.
Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
Farhan Rana, Sandip Tiwari, et al.
Superlattices and Microstructures