SI-SIC LAYERED SEMICONDUCTOR DEVICES PREPARED BY RAPID THERMAL CHEMICAL VAPOR DEPOSITION

SILICON CARBIDE (SIC) HAS LONG BEEN KNOWN AS AN ATTRACTIVE MATERIAL FOR HIGH TEMPERATURE, HIGH POWER, AND HIGH FREQUENCY ELECTRONIC DEVICES BECAUSE OF ITS LARGE BAND GAP, GOOD CARRIER MOBILITY, AND EXCELLENT PHYSICAL STABILITY. RECENT PROGRESS IN THE CHEMICAL VAPOR DEPOSITION OF EPITAXIAL LAYERS OF SIC ON SINGLE CRYSTAL SILICON SUBSTRATES HAVE INCREASED THE INTEREST IN THIS MATERIAL. PROBLEMS WITH OBTAINING LARGE AREA HIGH QUALITY FILMS REMAIN ASSOCIATED CHIEFLY WITH STRESS INDUCED CRACKING IN THE FILMS. ONE WAY TO REDUCE THE STRESS IN FILMS IS BY COMPOSITIONAL GRADING OVER DISTANCES OF 10 TO 30 MICRONS. THE APPROACH PROPOSED IN THIS WORK IS TO APPLY THE CONCEPTS EMPLOYED IN STRAINED LAYER SUPERLATTICE MATERIAL TOGETHER WITH THE CHEMICAL VAPOR DEPOSITION TECHNIQUE THAT USE A RAPID THERMAL SWITCH TO TURN ON AND OFF THE KINETICS OF FILM DEPOSITION. IN THIS WAY ALTERNATE LAYERS OF SI AND SIC CAN BE GROWN EPITAXILLY TO OBTAIN A LAYERED STRUCTURE THAT IS DEFECT FREE AND HAS AN OPTICAL BEND GAP THAT IS DETERMINED BY THE RATIO OF THE LAYER THICKNESSES.