Minority carrier lifetime in doped and undoped p-type Cd_xHg_1-xTe

Abstract

Photoconductive lifetime measurements have been carried out on thick samples of both doped and undoped slices of p-type Cd,Hg,-,Te prepared by Bridgman and accelerated crucible rotation (ACRT) Bridgman techniques. Means of reducing and/or allowing for surface recombination from front and back surfaces are described. The four recombination mechanisms thought to be the most important in p-type material are outlined and compared to the experimental results. An analysis of lifetime versus temperature variations suggests that the Auger-7 recombination mechanism is not important for our p-type material grown by the Bridgman technique. Measurements of lifetime in material covering a wide range of carrier concentration values confirms this view. An investigation of ZnS passivation on both n-and p-type material suggests that it can be a useful passivation for photovoltaic n-on-p devices.

Numerical modeling of fluctuation phenomena in semiconductors and detailed noise study of mid-wave infrared HgCdTe-heterostructure devices

“…be assumed; 14 alternatively, for n-type material, n0 Ϸ p0 Ϸ 1 s. 15,16 The spectral intensity of the second component in Eq. 9 may be expressed by the spectral intensity of the fluctuations ␦⌿, ␦⌽ n , and ␦⌽ p .…”

“…(13) If we neglect the fluctuations of bias voltage, the fluctuations of the current may be expressed by (14) We focus on the first component, which is dominating. (13) If we neglect the fluctuations of bias voltage, the fluctuations of the current may be expressed by (14) We focus on the first component, which is dominating.…”

Noise modeling in HgCdTe heterostructure devices

“…For p-type material we have taken p 0 Ϸ100 n 0 and n 0 ϭ150 ns, 12 and for n-type material we have assumed p 0 Ϸ n 0 Ϸ1 s. 13,14 The terms 1 i and 7 i denote the Auger 1 and Auger 7 lifetimes in intrinsic material, respectively, n i is the intrinsic carrier concentration, G R is the radiative recombination rate 15 and n 0 and p 0 are the electron and hole concentrations in equilibrium.…”

Room temperature photoinduced Faraday rotation in Hg1−xMnxTe alloys at 1550 nm

“…15 The quantity ϭm e /m h , m e and m h being electron and hole effective masses, is of the order of 10 Ϫ3 . 18 Finally, radiative lifetime can be expressed as: 16 Casselman 17 carried out theoretical calculations concerning Auger-7 lifetime.…”