Electronics and Telecommunications Research Institute

Byung Ryul Ryum

Soo Min Lee

Deok Ho Cho

Tae Hyeon Han

Kwang Eui Pyun

Disclosed is a super self-aligned heterojunction bipolar transistor which is capable of miniaturizing an element, simplifying the process step thereof without using a trench isolation process and a sophisticated selective epitaxial growth (SEG) processes. According to this invention, the sophisticated isolation and the SEG techniques are derived by using simple and popular processes. The base layer has multi-layer structure being made of a Si, an undoped SiGe, a SiGe doped a p-type impurity in-situ and Si. Also, the selective epitaxial growth is not required. Thus, it can be less prone to a flow of leakage current or an emitter-base-collector short effect.

Super self-aligned bipolar transistor and method for fabricating thereof

There is disclosed a method of manufacturing a silicon/silicon germanium heterojunction bipolar transistor having a good conformity and an improved speed characteristic, which includes the steps of sequentially laminating an underlying nitride film, an oxide film, a polycrystalline silicon film and an upper nitride on a semiconductor substrate on which devices are separated and a collector is formed; sequentially etching said upper nitride film and said polycrystalline silicon film using the emitter as a mask, and then forming a side wall nitride film; selectively wet-etching said oxide film to form a side base linker opening; burying said base linker opening with a polycrystalline silicon; oxidizing said polycrystalline silicon film buried into said base linker opening and then removing said oxide film by means of the selective wet-etch process; removing said upper nitride and then forming a silicon/silicon germanium film as a base film on the exposed thereof; and forming an emitter said silicon/silicon germanium film.

Growing community of inventors

Daejeon, South Korea

Byung Ryul Ryum