Preparation And Related Basic Research Of Ultra - Lattice Infrared Explosive Materials Of Low - Dark Current Sulfide

In this paper, we studied deeply and systematically low tempera ture Ga Sb, In As Sb materials, and In As/In As Sb superlattice grown on Ga Sb(001) substrate by molecular beam epitaxy(MBE). The fabrication of In As Sb material and In As/In As Sb superlattice unit infrared detector have been also explored. The electrical and optical properties were systematically investigated. The main contents are as follows:1. MBE growth of Low-temperature Ga Sb layer on Ga Sb substrate was investigated. By optimizing growth temperature and Sb/Ga beam equivalent pressure(BEP) ratio, pyramidal mounds on Ga Sb surface were eliminated, and the quality of Low-temperature Ga Sb layer was also improved. The optimal growth conditions for the growth of the Low-temperature Ga Sb layer were that the growth temperature was Tc + 60°C and the ratio of Sb to Ga(V/III) was about 7.1, when the cracker tip temperature and base temperature for Sb cells were 900°C and 580°C respectively.2. The high-quality In As Sb material was grown based on optimized growth conditions. We have fabricated PIN-type In As Sb mid-wave infrared photodetector and infrared photodetectors containing In As Sb absorber regions and Al As Sb barriers in n-barrier-n(NBN) and n-barrier-p(NBP) configurations, and characterized them by current- voltage and photocurrent. The dynamic resistance of the PIN-type In As Sb photodetector was 224 Ω·cm2(100K), the peak detectivity was 3.6×1010 cm Hz1/2/W(77K). At 100 K, the dynamic resistance of the NBP and the N BN near zero bias were approximately an order of 105 magnitude, but the dynamic resistance of the NBP less than the dynamic resistance of the n Bn biased for high responsivity, indicating that the reduction in shot noise achieved by operating the NBP near zero bias may be offset by an increase in Johnson noise. At 77 K, the peak detectivity of the NBP and the NBN separately were 8.5×1012 cm Hz1/2/W and 2.4×108 cm Hz1/2/W. Finally, the 50% cut-off wavelength of 3.8μm(PIN-type), 3.4μm(NBP-type), 2.6μm(NBN-type) In As Sb detectors have been achieved.3. MBE Growth and characterization of In As/In As Sb superlattices material on Ga Sb substrates were investigated. By optimizing growth temperature and Sb/Ga beam equivalent pressure(BEP) ratio, the quality of long-period thickness(75 periods) In As/In As0.73Sb0.27 superlattices material was also improved. The RMS of the optimized long-period thickness(75 periods) In As/In As0.73Sb0.27 SL sample was around 1.8 ? over an area of 20 μm × 20 μm. The mismatch between the zeroth-order peak of the optimized long period thickness(75 periods) In As/In As0.73Sb0.27 SL and the Ga Sb substrate peak was approximately 100 arcsec, while the FWHM of the zeroth-order peak was below 130 arcsec with a measured period of 93.3 Angstrom for the grown devices. PIN-type In As/In As Sb superlattice photovoltaic detectors were fabricated. At 77 K, the achieved 50% cutoff wavelength of the device was 5.1 μm and the dynamic resistance(R0A) of 448 Ω·cm2.