A THIN FILM RESISTOR NOISE SOURCE
Original Publication Date: 1983-Mar-01
Included in the Prior Art Database: 2001-Oct-10
Publishing Venue
Motorola
Related People
David Hughes: AUTHOR [+2]
Abstract
This invention relates to a new method of fabricating semiconductor noise sources and, more par- ticularly, relates to a technique for manufacturing noise sources integrated with additional semicon- ductor circuitry.
Volume 3 March 1983
A THIN FILM RESISTOR NOISE SOURCE
By David Hughes, John Price and Ray Roop
This invention relates to a new method of fabricating semiconductor noise sources and, more par- ticularly, relates to a technique for manufacturing noise sources integrated with additional semicon- ductor circuitry.
It has been customary to perform noise generation by using an avalanching junction. Such an ap- proach does not readily lend itself to integrated circuits because the processing appropriate to the re- mainder of the circuit does not produce adequately noisy junctions.
An object of the present invention is to provide a noise source which can be co-fabricated with con- ventional semiconductor circuitry without compromising either segment of the enterprise. The present invention is embodied in a noise generator formed at the oxidized interface between a resistive film and a metallic contact constructed as discussed below.
The invention will be illustrated by the accompanying drawing in which a semiconducting substrate (1) is covered by an epitaxial layer (2), and a dielectric film (3) prior to the evaportion of a chromium-silicon composite layer. The chromium-silicon composite film or layer is patterned into a resistor (4). The surface of the chromium-silicon layer is slightly oxidized. Metallic contacts (5) are ap- pended to the ends of the chromium-silicon resistor without removing the slight oxidation. Aluminum
Is a suitable material for the metal contacts...