Isothermal vapor phase epitaxial growth of large-area HgCdTe film on lattice-matched CdZnTe substrate

Hg_1-xCd_xTe(x=0.3) epilayers(ø=26 mm) have been grown by isothermal vapor phase epitaxial(ISOVPE) method on each substrate of (110) and (111)CdZnTe with area over 600 mm²(ø=30 mm). The crystallinity of HgCdTe epilayer has been measured by double crystal x-ray rocking curve and the full width at half maximum(FWHM) was about 100 arcsec. The lateral variation of x composition over the whole HgCdTe epilayer was found to be ±0.003 by measuring through infrared transmission spectra. The crosssectional variation over the 10 μm thickness of the film measured by electron probe microanalysis (EPMA) is ±0.005. As-grown HgCdTe epilayers are p-type with low 10¹⁷ cm^-3 in carrier concentration and 100 cm²/Vs in mobility at 77 K. After Hg vacancy annealing at 260°C for 24 hrs, the epilayer has been converted to n-type with low 10¹⁴ cm^-3 in carrier concentration and 200 cm²/Vs in mobility at 77 K.