Electrical properties and deep levels spectra of bulk SiC crystals grown by hybrid physical–chemical vapor transport method

• Published in: Journal of crystal growth Vol. 300; no. 2; pp. 314 - 318
• Main Authors: Fanton, M.A., Li, Q., Polyakov, A.Y., Skowronski, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2007; Elsevier
• Subjects: A1. Point defects; A2. Growth from vapor; A3. Physical vapor deposition processes; B2. Semiconducting silicon compounds; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects and impurities in crystals; microstructure; Defects and impurities: doping, implantation, distribution, concentration, etc; Electron states; Exact sciences and technology; Impurities: concentration, distribution, and gradients; Impurity and defect levels; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Other nonmetals; Physics; Structure of solids and liquids; crystallography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; A1. Point defects; B2. Semiconducting silicon compounds; A3. Physical vapor deposition processes; 68.55.L; 71.55.H; 61.72.S; A2. Growth from vapor; Crystal growth; Charge carriers; Electrical properties; Sublimation; Silicon carbides; Secondary ion mass spectrometry; Experimental study; 61.72.S; 68.55.L; 71.55.H; Non oxide ceramics; CVD; Electrical measurement; Electron traps; Secondary ion mass spectra; Chemical transport; Growth mechanism; Physical vapor deposition; Al. Point defects; A2. Growth from vapor; A3. Physical vapor deposition processes; B2. Semiconducting silicon compounds; Deep energy levels
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2007.01.002

Concentrations of nitrogen shallow donors, boron shallow acceptors, charge carriers, and electron traps were measured as a function of position along the growth axis in a series of undoped 6H–SiC boules grown by sublimation method with and without addition of hydrogen to the growth atmosphere. Elemental analysis by secondary ion mass spectrometry and measurements of electrical properties indicate that the addition of hydrogen suppresses nitrogen incorporation and formation of all electron traps. Concentration of boron is not affected by hydrogen presence. The addition of hydrogen to the growth ambient improves the uniformity of nitrogen incorporation and deep trap distribution along the growth axis. The results are interpreted as due to increased carbon transport and corresponding shift of crystal stoichiometry toward carbon-rich side of the SiC existence range.