Analysis of Electrically Active Carbon in Semi-insulating Gallium Arsenide by Infrared Absorption Spectroscopy

• Published in: Japanese Journal of Applied Physics Vol. 38; no. 12R; p. 6611
• Main Authors: Alt, H. Ch, Wiedemann, B., Meyer, J. D., Michelmann, R. W., Bethge, K.
• Format: Journal Article
• Language: English
• Published: 01.12.1999
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.38.6611

Carbon in semi-insulating gallium arsenide (GaAs) crystals has been investigated by Fourier-transform IR absorption spectroscopy, spark source mass spectrometry, and charged particle activation analysis. Procedures for the quantitative evaluation of the 582-cm -1 local mode absorption due to carbon on the arsenic sublattice ( C As ) are described. The strength of the mode shows a linear correlation with total carbon content measured by spark source mass spectrometry over the concentration range from 3× 10 14 to 2×10 16 cm -3 . The new calibration factor for the integrated absorption at 77 K is (7.2±0.4)× 10 15 cm -1 , based on a relative sensitivity coefficient of 3.2±0.1 of the spark source mass spectrometry. Calibration factors for the IR absorption method at room temperature are also given.