US 2025/0098195 A1 · IMPURITY REDUCTION TECHNIQUES IN GALLIUM NITRIDE REGROWTH

Abstract

Various techniques for impurity dopant reduction in GaN regrowth are described. In a first technique, a barrier layer, such as AlN, can be formed at a regrowth interface before the regrown GaN layer. The barrier layer can bury the impurities at the regrowth interface and reduce their effect on the layers above that include the channel of the device, e.g., transistor. In a second technique, a buffer layer, such as a carbon-doped GaN layer, can be formed at the regrowth interface before the regrown GaN layer. Carbon can act as an acceptor to compensate for the dopants. e.g., silicon, and cancel their electronic effect on the above layers. In a third technique, a hydrogen bake treatment can be performed before the GaN regrowth. Hydrogen can desorb a thin layer of GaN at the regrowth interface, which is the GaN layer with the highest concentration of impurities.

Claims20

Dependent claims

A method of forming a semiconductor device to reduce or counteract impurities at a regrowth interface, the method comprising:

forming a first semiconductor growth region, including:
forming a first buffer layer of a first compound semiconductor material on a substrate;
forming a first channel layer with the first buffer layer;
forming a first barrier layer with the first channel layer thereby forming a first heterostructure, the first heterostructure configured to form a first two-dimensional electron gas (2DEG) channel;
reducing or counteracting impurities at the regrowth interface;
and
forming a second semiconductor growth region at the regrowth interface, including:
forming a second heterostructure with the first semiconductor growth region, the second heterostructure configured to form a second 2DEG channel and comprising a second channel layer;
and
forming first and second spaced apart contact materials coupled to the second channel layer.

7 more elements

Dependencies are inferred from the claim text.

Impurity reduction techniques in gallium nitride regrowth

Life of this patent

Impurity reduction techniques in gallium nitride regrowth

Life of this patent

Abstract

Claims20