Reduction of Thermal Stress Induced Defects for Indium Phosphide Bulk Crystal Growth

Period of Performance: 09/13/1994 - 09/12/1995

$99.5K

Phase 1 STTR

Recipient Firm

Creare, Inc.
16 Great Hollow Road Array
Hanover, NH 03755
Principal Investigator
Firm POC

Research Institution

Florida Atlantic University
777Glades Rd.
Boca Raton, FL 33431
Institution POC

Abstract

This STTR project will improve blulk crystal growth of indium phosphide (InP) by reducing thermal stress induced defects (TSIDs). This will be accomplished bymodifying a vertical Bridgman (VB) furnace currently available at Lincoln Laboratory for InP crystal growth. During Phase I, we will develop computational models for simulating the distribution of temperature and thermal stresses in the growing crystal. These models will be used to predict the evolution and distribution of TSIDs. Reducing TSIDs will be the criteria for the furnace design modifications. During Phase II, furnace design modifications will be implemented and tested during InP crystal growth. The furnace modifications will incorporate hardware developed at Creare which improves the temperature distribution near the growth interface. We are currently developing methods for real-time control of this temperature distribution. This STTR project will provide design closure -- the relationship betwen thermal design, control actions and the resultant defect density in the as-grown crystal. Quantitative prediction of defect density during crystal growth has only recently become useful through the application of new models for TSID evolution. Prof. C.T. Tsai of Florida Atlantic University is a leader in this area and will collaborate with Creare during the proposed STTR project.