Browse Prior Art Database

Improved Ohmic Contacts for Semi Conductive Devices

IP.com Disclosure Number: IPCOM000095821D
Original Publication Date: 1964-Jul-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 19K

Publishing Venue

IBM

Related People

Kessler, HK: AUTHOR [+2]

Abstract

When fabricating contacts on a P-N device having an epitaxial junction, the initial deposition of rhodium, or a rhodium alloy, prevents the diffusion of subsequently deposited contact metal into the junction region, allows relatively low temperatures to be maintained during the fabrication process, and increases contact adherence.

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

Improved Ohmic Contacts for Semi Conductive Devices

When fabricating contacts on a P-N device having an epitaxial junction, the initial deposition of rhodium, or a rhodium alloy, prevents the diffusion of subsequently deposited contact metal into the junction region, allows relatively low temperatures to be maintained during the fabrication process, and increases contact adherence.

Semiconductive device 10 has a shallow junction region 12 formed by epitaxially depositing a layer of P-type material onto an N-type substrate. A layer 14 of rhodium, or rhodium alloy, e. g., rhodium-gold, is then deposited using conventional deposition techniques onto the P-type material. An ohmic contact is formed by depositing layer 16 of gold, or gold-tin solder.

Rhodium, or rhodium alloy, layer 14 prevents diffusion of the gold or gold-tin solder into the PN-junction. In addition, contact adherence is improved. Further, should semiconductive device 10 be fabricated from gallium arsenide, thermal expansion problems are mitigated since the coefficient of thermal expansion for rhodium an gallium arsenide are substantially equal. Lastly, the maximum temperature reached during the fabrication process is 340 degrees C. Such a low temperature prevents the thermal destruction of the PN-junction.

1

Page 2 of 2

2

[This page contains 1 picture or other non-text object]