Patent ID: 6566693
Filing Date: 2003-05-20
Classification: H01L,Y10S

Abstract:
A method for fabricating a heterojunction bipolar transistor (HBT), wherein the HBT comprises an emitter, a collector and a base, wherein the collector and the base form a base-collector mesa, and the HBT further comprises a sub-collector mesa, an emitter metal contact, a self-aligning base metal contact, a base post, a collector metal contact, and a collector post or via, wherein the base is positioned between the emitter and the collector and, accordingly, the base-collector mesa is sandwiched between the emitter and the sub-collector mesa, and the method comprises the steps of:a. patterning the emitter metal contact; b. depositing the emitter metal contact on the emitter, incompletely covering the emitter; c. etching the emitter not covered by the emitter metal contact to expose the base; d. patterning the self-aligned base metal contact; e. depositing the self-aligned base metal contact on the base and emitter metal contact, incompletely covering the base; f. patterning the base post; g. depositing the base post on the self-aligned base metal contact; h. patterning the base collector-mesa on the base not covered by the self-aligning base metal contact; i. etching the base not covered by the self-aligned base metal contact to fabricate the base-collector mesa and define and incompletely expose the sub-collector mesa; j. patterning the collector metal contact; k. depositing the collector metal contact on the sub-collector mesa exposed by fabricating the base-collector mesa; l. patterning the collector post or via, and m. depositing the collector post on the collector metal contact or etching a collector via through a subsequent insulating film to the collector metal contact.