Backside copper metallisation of GaAs MESFETs

Author

Chen, C.Y. ; Chang, E.Y. ; Chang, L. ; Chen, S.H.

Author_Institution

Dept. of Mater. Sci. & Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

36

Issue

15

fYear

2000

fDate

7/20/2000 12:00:00 AM

Firstpage

1317

Lastpage

1318

Abstract

Backside copper metallisation of GaAs MESFETs is studied. A thin Ta layer of 40 nm was sputtered on a GaAs substrate as the diffusion barrier before copper film metallisation. X-ray diffraction data show that the Cu/Ta films with GaAs were very stable up to 500°C. After annealing at 300°C for two hours, the copper-metallised MESFETs showed very little change in terms of their device characteristics. The changes in the electrical parameters and RF characteristics of the devices after annealing were of the same order as those devices without Cu metallisation. These results show that Ta is a good diffusion barrier for Cu in GaAs devices and that Cu/Ta films can be used for the backside copper metallisation of GaAs devices

Keywords

III-V semiconductors; Schottky gate field effect transistors; X-ray diffraction; annealing; copper; diffusion barriers; gallium arsenide; semiconductor device metallisation; sputtered coatings; tantalum; 300 C; 40 nm; 500 C; Cu-Ta-GaAs; Cu-metallised MESFETs; Cu/Ta films; GaAs MESFETs; RF characteristics; Ta diffusion barrier; X-ray diffraction data; annealing; backside Cu metallisation; device characteristics; electrical parameters; thin Ta layer;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el:20000917

Filename

856231