Electrical properties of low-arsenic-doped HgCdTe grown by molecular beam epitaxy

A study of the electrical properties of p-type, low-arsenic-doped Hg1-xCdxT e (x similar to0.3, carrier concentration similar to 1x10(+15) cm(-3)) suit able for fabrication of high-operating-temperature photodetectors was carri ed out. The arsenic-doped HgCdTe samples were prepared by molecular beam ep itaxy using an elemental arsenic source and were characterized by Hall meas urements at 77 K after the samples were subjected to four different arsenic activation annealing schemes with annealing temperatures ranging from 300 to 450 degreesC. For comparison purpose, a sample doped to low-10(+16) cm(- 3) was also prepared and subjected to the same annealing schemes. Although the four annealing schemes had little influence on the Hall data of the 10( +16) cm(-3) sample, they had significant impact on the Hall data of the 10( +15) cm(-3) sample. Furthermore, it was found that the Hall data could not be explained by any scattering mechanisms but could be satisfactorily model ed by a two-layer model in which an n-type skin layer is included. (C) 2001 American Institute of Physics.