Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Increased Bipolar f(T) with One Step Emitter Etch

IP.com Disclosure Number: IPCOM000049893D
Original Publication Date: 1982-Aug-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Heimeier, HH: AUTHOR [+4]

Abstract

Shallow device structures result in increased f(T) because the transit time t(e) is reduced. t(e) is a partial result of minority charge stored in the emitter so that if less charge is stored when the emitter is made shallower, f(T) will increase.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Increased Bipolar f(T) with One Step Emitter Etch

Shallow device structures result in increased f(T) because the transit time t(e) is reduced. t(e) is a partial result of minority charge stored in the emitter so that if less charge is stored when the emitter is made shallower, f(T) will increase.

Shown in the figure is a cross section of a bipolar transistor having a collector region 10, a base region 11, and an emitter region 12. To achieve a shallow emitter, the emitter region 12 is etched, as shown by the dashed line 13, using, for example, reactive ion etching techniques. By masking, some of the emitters of the bipolar transistors in an integrated circuit chip can be etched while some can be masked so as to permit transistors of different f(T) in the integrated circuit.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]