ISSN:
1432-0630
Keywords:
61.40
;
85.30
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The modification of the emitter structure of silicon bipolar transistors results in more freedom in the choice between sometimes conflicting device parameters. The approach followed in this work is the use of an amorphous silicon (a-Si:H) or microcrystalline silicon (μc-Si) emitter, creating a real heterojunction with the crystalline silicon base. Due to the larger bandgap of these emitter materials, the back injection of minority carriers is strongly suppressed in comparison with conventional bipolar transistors. Furthermore, the small temperature coefficient of the current gainβ allows the use of these heterojunction bipolar transistors (HBT) over a wide temperature range. Most likely, the biggest advantage of such HBTs is that a better high-frequency behaviour could be obtained. However, some problems still need to be solved such as the recombination at the emitter-base interface and the high resistivity of the emitter material.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00616051
Permalink