THE REALIZATION OF A WIDE BAND GAP EMITTER TRANSISTOR.
Abstract
A Ge-GaAs wide band gap emitter transistor was realized that exhibits useable current gain. Useable current gains of about 15 are observed in a structure with an n-GaAs wide band gap emitter and a p-n Ge base-collector region at current densities up to 3500 A/sq cm. A typical device has a collector doping of 10 to the 16th power/cu cm, a 1 to 2 micron wide strongly graded diffused base with a maximum doping level of 5 . 10 to the 19th power/cu cm, and a thin emitter doped to 5 . 10 to the 16th power/cu cm. The attainment of current gain in a structure with the base region more heavily doped than the wide band gap emitter region is in agreement with Kroemer's 'Wide Band Gap Emitter' theory. A heterojunction transistor with a heavily doped and low resistance base region in conjunction with a more lightly doped emitter region has two distinct advantages over a comparable gain homojunction transistor. Both the emitter capacitance and transverse voltage drops are reduced resulting in possible improvements in high frequency performance and uniformity of current distribution in the device. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1967
- Accession Number
- AD0664784
Entities
People
- Dale K. Jadus
Organizations
- Carnegie Mellon University