Backside copper metallization of GaAs MESFETs using TaN as the diffusion barrier

Author

Chen, Chang-You ; Chang, Li ; Li Chang ; Chen, Szu-Hung

Author_Institution

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

Volume

48

Issue

6

fYear

2001

fDate

6/1/2001 12:00:00 AM

Firstpage

1033

Lastpage

1036

Abstract

Backside copper metallization of GaAs MESFETs using TaN as the diffusion barrier was studied. A thin TaN layer of 40 nm was sputtered on the GaAs substrate before copper film metallization, as judged from the data of X-ray diffraction (XRD), Auger electron spectroscopy (AES), and cross-sectional transmission electron microscopy (TEM), the Cu/TaN films with GaAs were very stable without interfacial interaction up to 550°C annealing; the copper metallized MESFETs were thermally stressed at 300°C. The devices showed very little change in the device characteristics (<3%) after thermal stress, and the changes of the electrical parameters and RF characteristics of the devices after thermal stress were of the same order as those devices without Cu metallization, these results show that TaN is a good diffusion barrier for Cu in GaAs devices and the Cu/TaN films can be used for the backside copper metallization of GaAs MESFETs

Keywords

Auger electron spectroscopy; III-V semiconductors; Schottky gate field effect transistors; X-ray diffraction; copper; diffusion barriers; gallium arsenide; semiconductor device metallisation; tantalum compounds; transmission electron microscopy; 300 degC; 40 nm; 550 degC; Auger electron spectroscopy; GaAs-TaN-Cu; MESFETs; RF characteristics; X-ray diffraction; backside metallization; cross-sectional transmission electron microscopy; device characteristics; diffusion barrier; electrical parameters; interfacial interaction; Copper; Electrons; Gallium arsenide; MESFETs; Metallization; Spectroscopy; Substrates; Thermal stresses; X-ray diffraction; X-ray scattering;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.925222

Filename

925222