US 12,113,125 B2 · Bipolar transistor having collector with doping concentration discontinuity

Abstract

This disclosure relates to bipolar transistors, such as heterojunction bipolar transistors, having increased collector thickness for improved ruggedness. In some embodiments, the collector thickness can be above 1.1 microns. The collector can have at least one doping concentration grading. The collector can have a high doping concentration at a junction between the collector and the sub-collector, such as at the high end of the grading. In some embodiments, the high doping concentration can be above about 9×1016 cm−3. The collector can include a region with high doping concentration adjacent the base. The collector can include a discontinuity in the doping concentration, such as at the low end of the grading. Such bipolar transistors can be implemented, for example, in power amplifiers.

Claims28

Dependent claims

A bipolar transistor comprising:

an emitter;
a base;
and
a collector having a first collector region and a second collector region, the first collector region between the base and the second collector region, the first collector region having a flat doping concentration, the second collector region having a graded doping concentration that increases along a direction away from the base, a transition from the flat doping concentration of the first collector region to the graded doping concentration of the second collector region having a step increase in the doping concentration, the collector having an additional collector region between the base and the first collector region, and the additional collector region having a doping concentration that is higher than the doping concentrations of the first collector region and the second collector region.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

17/809,855Filed 29 Jun 2022 · us provisional application

Priority

30 Jun 2021

Published

US 2023/0006055 A15 Jan 2023

Granted

8 Oct 2024

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

H10D 10/821
Heterojunction BJTs: vertical heterojunction BJTs
H10D 62/137
Semiconductor regions connected to electrodes carrying current to be rectified, amplified or switched, e.g. source or drain regions: collector…
H10D 62/60
Semiconductor bodies, or regions thereof, of devices having potential barriers: impurity distributions or concentrations
H10D 62/824
Heterojunctions: comprising only Group III-V materials heterojunctions, e.g. GaN/AlGaN heterojunctions

Bipolar transistor having collector with doping concentration discontinuity

Life of this patent

Bipolar transistor having collector with doping concentration discontinuity

Life of this patent

Abstract

Claims28