High-Purity Semi-Insulating 4H-SiC Grown by the Seeded-Sublimation Method
Authors: Jenny, J. R.; Müller, St. G.; Powell, A.; Tsvetkov, V. F.; Hobgood, H. M.; Glass, R. C.; Carter, C. H.
Source: Journal of Electronic Materials, Volume 31, Number 5, 1 May 2002 , pp. 366-369(4)
Abstract:The growth of high-purity, semi-insulating (HPSI) 4H-SiC crystals has been achieved using the seeded-sublimation growth technique. These semi-insulating (SI) crystals (2-inch diameter) were produced without the intentional introduction of elemental deep-level dopants, such as vanadium, and wafers cut from these crystals possess room-temperature resistivities greater than 109 Ωcm. Based upon temperature-dependent resistivity measurements, the SI behavior is characterized by several activation energies ranging from 0.9-1.5 eV. Secondary ion mass spectroscopy (SIMS) and electron paramagnetic resonance (EPR) data suggest that the SI behavior originates from deep levels associated with intrinsic point defects. Typical micropipe densities for wafers were between 30 cm-2 and 150 cm-2. The room-temperature thermal conductivity of this material is near the theoretical maximum of 5 W/mK for 4H-SiC, making these wafers suitable for high-power microwave applications.
Document Type: Research Article
Publication date: 1 May 2002