Form 9.B Project Summary






Project Title:

Metalorganic Chemical Vapor

Deposition Grown GaAs Junction

Field-effect Transistors for Low-noise

Deep-cryogenic Readouts

Technical Abstract (Limit 200 words)

Low-noise readout electronics are needed in

cryogenic detection systems for applications

including earth- and space-based observation.

Compared to conventional electronics, Si- and

GaAs-based junction field effect transistors

(JFETs) offer the best low-noise performance. At

extremely low temperatures, GaAs JFETs are

preferred because they offer "hopping" transport

and do not suffer from freezeout problems of Si

JFETs. While several groups have fabricated GaAs

JFETs using MBE, these devices have not

achieved their theoretical performance due to a

variety of reasons. Spire proposes to develop GaAs

JFETs using metalorganic chemical vapor

deposition (MOCVD), since this process provides

material with longer carrier lifetimes and different

characteristic traps and defects than MBE-grown

material, to produce extremely low-noise devices.

In Phase I, Spire will demonstrate proof-of-concept

by depositing and fabricating large-gate JFETs and

identify optimum MOCVD procedures for the best

devices. In Phase II, the development will be

extended to develop devices and integrated circuits

for specific applications.

Potential Commercial Applications (Limit 200 words)

Low-noise JFETs will be important components for

enabling low-noise readout electronics for space-

and earth-based telescopes. In addition, they will

find applications in sensing and detection of

extremely low level signals.

Name and Address of Principal Investigator (Name,

Organization Name, Mail Address, City/State/Zip)

Peter C. Colter

Spire Corporation

One Patriots Park

Bedford , MA 01730-2396

Name and Address of Offeror (Firm Name, Mail Address,


Everett S. McGinley

Spire Corporation

One Patriots Park

Bedford , MA 01730-2396