ABSTRACT
CONTENTS 21.1 Introduction ...................................................................................................................... 615 21.2 Shallow Levels.................................................................................................................. 617
21.2.1 Electronic Structure of the Shallow Donors and Acceptors ......................... 617 21.2.2 EMT....................................................................................................................... 619 21.2.3 DAP Luminescence from N-Al and P-Al Pairs............................................. 622 21.2.4 Raman Scattering from Donor States............................................................... 624 21.2.5 EPR Measurements and Related Theoretical Studies.................................... 625 21.2.6 PL from Excitons Bound to Shallow Donors and Acceptors ....................... 626
21.3 Intrinsic Defects................................................................................................................ 630 21.3.1 Introduction ......................................................................................................... 630 21.3.2 Carbon Vacancy VC............................................................................................ 631 21.3.3 Silicon Vacancy VSi ............................................................................................. 634 21.3.4 Carbon Antisite-Carbon Vacancy Complex CSiVC........................................ 637 21.3.5 Divacancy VSiVC ................................................................................................. 639 21.3.6 Interactions between Defects and Their Role in SI Substrates..................... 641
21.4 Unknown Defects Found in SI Substrates ................................................................... 644 21.4.1 PL Results............................................................................................................. 644 21.4.2 EPR Results .......................................................................................................... 648
21.5 Metallic Impurities, Irradiation-Induced Defects, and Unknown Defects .............. 651 21.5.1 Metallic Impurities.............................................................................................. 651 21.5.2 Irradiation-Induced Defects and Unknown Defects...................................... 653
21.5.2.1 EPR and DLTS..................................................................................... 653 21.5.2.2 PL Results ............................................................................................. 655
21.5.3 Others ................................................................................................................... 659 References.................................................................................................................................... 660
More than 200 polytypes of SiC are known but only a few have been explored so far for industrial applications. These are the hexagonal 4H and 6H polytypes, as well as the cubic 3C polytype, which has the zinc blende structure. Since these are also the most studied polytypes, our attention will mainly be restricted to them.
