TY - JOUR
T1 - Surface mapping of carrier density in a GaN wafer using a frequency-agile THz source
AU - Ohno, Seigo
AU - Hamano, Akihide
AU - Miyamoto, Katsuhiko
AU - Suzuki, Chisato
AU - Ito, Hiromasa
PY - 2009
Y1 - 2009
N2 - We developed a method for mapping the carrier density on a semiconductor substrate surface based on terahertz (THz)-reflective measurement. Reflectivity in the THz-frequency region away from the optical phonon frequency is sensitive to the carrier density in semiconductors. However, reflectivity in the optical phonon frequency regions is around 1.0, independent of the carrier density. We developed a THz-reflective spectral imaging system using a frequency-agile, ultra-widely tunable THz source (1-40 THz). Different reflective images were obtained from GaN samples of carrier density 2.5 × 1016 cm-3, 1.0 × 1018 cm-3 and 1.5 × 1018 cm-3 using 22.7 and 26.5 THz. The image contrast reflected the GaN crystals' carrier density.
AB - We developed a method for mapping the carrier density on a semiconductor substrate surface based on terahertz (THz)-reflective measurement. Reflectivity in the THz-frequency region away from the optical phonon frequency is sensitive to the carrier density in semiconductors. However, reflectivity in the optical phonon frequency regions is around 1.0, independent of the carrier density. We developed a THz-reflective spectral imaging system using a frequency-agile, ultra-widely tunable THz source (1-40 THz). Different reflective images were obtained from GaN samples of carrier density 2.5 × 1016 cm-3, 1.0 × 1018 cm-3 and 1.5 × 1018 cm-3 using 22.7 and 26.5 THz. The image contrast reflected the GaN crystals' carrier density.
KW - Carrier density
KW - GaN
KW - Imaging systems
KW - Terahertz spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=68949191211&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=68949191211&partnerID=8YFLogxK
U2 - 10.2971/jeos.2009.09012
DO - 10.2971/jeos.2009.09012
M3 - Article
AN - SCOPUS:68949191211
VL - 4
JO - Journal of the European Optical Society-Rapid Publications
JF - Journal of the European Optical Society-Rapid Publications
SN - 1990-2573
M1 - 9012
ER -