Patent · US Expired

Heterojunction bipolar transistor and its fabrication method

US6395608B2 · kind B2 · utility

6Cited by
3References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 2001
Grant dateMay 28, 2002
Priority date
Expiry dateJan 29, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A heterojunction bipolar transistor and its fabrication method is disclosed. The heterojunction bipolar transistor includes a substrate; a collector layer formed to have a ledge or MESA on the substrate; a collector electrode formed on the collector layer surrounding the ledge; a base layer formed on the ledge of the collector layer; an ohmic cap layer on the emitter layer; an emitter layer formed in the center of the base layer; an emitter electrode formed on the ohmic cap layer; a base electrode formed on the base layer surrounding the emitter electrode; an insulating layer formed to cover the base electrode and to overlay on the insulating layer; a metal wire formed to cover the emitter electrode; and an air bridge brought in contact with the metal wire and electrically connected to an external pad lying on an ion-implanted isolation region.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.