SIR Physics Investigation Abstract
GATED FIELD EMITTERS USING N+ GAN
Presenter:
David J. Shea, Illinois Mathematics and Science Academy
Advisor:
Dr. Heinz Busta, Cabot Microelectronics Corporation
Abstract:
Gated cold electron sources offer a multitude of potential applications including flat panel vacuum fluorescent displays, ultrahigh-frequency power sources and amplifiers.
The standard gated field emitter is the Spindt emitter consisting of micromachined tungsten cones surrounded by an extraction gate. In this investigation we are using GaN threading dislocations as the cones. The advantage is that GaN is a rugged material that is chemically inert.
Fabrication of the array consists of coating the nano cones with 2000A of silicon dioxide followed by the deposition of 800A Cr and defining the gate region using standard photolithographic processing. A second mask is used to define the region where the oxide is removed from the cones. By applying a positive voltage to the Cr gate with respect to the GaN cone-shaped dislocations, electrons are pulled from the cones via quantum mechanical tunneling. This project consists of mask design, fabrication of the gated field emitter arrays and testing their performance in a high vacuum test station at a base pressure of about 1x10-8 torr.