InGaAs-InP mesa DHBTs with simultaneously high f/sub /spl tau// and f_max and low C/sub cb//I/sub c/ ratio

Author

Griffith, Z. ; Dahlstrom, M. ; Urteaga, M. ; Rodwell, M.J.W. ; Fang, X.-M. ; Lubyshev, D. ; Wu, Yaowu ; Fastenau, J.M. ; Liu, W.K.

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of California, Santa Barbara, CA, USA

Volume

25

Issue

5

fYear

2004

fDate

5/1/2004 12:00:00 AM

Firstpage

250

Lastpage

252

Abstract

We report an InP-InGaAs-InP double heterojunction bipolar transistor (DHBT), fabricated using a conventional triple mesa structure, exhibiting a 370-GHz f/sub /spl tau// and 459-GHz f_max, which is to our knowledge the highest f/sub /spl tau// reported for a mesa InP DHBT-as well as the highest simultaneous f/sub /spl tau// and f_max for any mesa HBT. The collector semiconductor was undercut to reduce the base-collector capacitance, producing a C/sub cb//I/sub c/ ratio of 0.28 ps/V at V/sub cb/=0.5 V. The V/sub BR,CEO/ is 5.6 V and the devices fail thermally only at >18 mW/μm², allowing dc bias from J/sub e/=4.8 mA/μm² at V/sub ce/=3.9 V to J/sub e/=12.5 mA/μm² at V/sub ce/=1.5 V. The device employs a 30 nm carbon-doped InGaAs base with graded base doping, and an InGaAs-InAlAs superlattice grade in the base-collector junction that contributes to a total depleted collector thickness of 150 nm.

Keywords

III-V semiconductors; capacitance; doping profiles; heterojunction bipolar transistors; semiconductor superlattices; 0.5 V; 1.5 V; 150 nm; 3.9 V; 30 nm; 370 GHz; 459 GHz; 5.6 V; C/sub cb//I/sub c/ ratio; InGaAs-InAlAs; InP-InGaAs-InP; base-collector capacitance; base-collector junction; carbon-doped InGaAs base; collector semiconductor; conventional triple mesa structure; double heterojunction bipolar transistor; graded base doping; superlattice grade; total depleted collector thickness; Current density; DH-HEMTs; Delay; Digital circuits; Doping; Double heterojunction bipolar transistors; Heterojunction bipolar transistors; Indium gallium arsenide; Indium phosphide; Parasitic capacitance;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2004.827288

Filename

1295097

InGaAs-InP mesa DHBTs with simultaneously high f/sub /spl tau// and fmax and low C/sub cb//I/sub c/ ratio

Griffith, Z. ; Dahlstrom, M. ; Urteaga, M. ; Rodwell, M.J.W. ; Fang, X.-M. ; Lubyshev, D. ; Wu, Yaowu ; Fastenau, J.M. ; Liu, W.K.

jour

InGaAs-InP mesa DHBTs with simultaneously high f/sub /spl tau// and f_max and low C/sub cb//I/sub c/ ratio