The experimental measurements together with the theoretical results indicate that the Bir_Aronov_Pikus (BAP) mechanism plays a dominant role for spin polarization decay, especially in band bending region of GaAs(100).
Upon the deposition of GaS,the band bending of the GaAs surface is found to be reduced by 0 4eV.It means that Fermi level pinning of the GaAs surface can be eliminated to a certain extent.
并发现 Ga S的淀积能使 Ga As原有的表面能带弯曲减小 0 .4e V,这意味着表面费米能级钉扎在一定程度上得到消除 .
Possible mechanisms of the dopant contrast are discussed, with a detailed description of two main mechanisms, band bending at the semiconductor surface, and the presence of a local surface field outside the specimen.
It is found that submonolayer Ba coatings induce cardinal changes in the electronic properties of the surface with the formation of a charge accumulation layer in the region of the near-surface band bending.
It is shown that the reversible temperature-induced changes in the surface band bending and the work function of Si have a stepwise character in the temperature range 80-300 K.
It is shown that holes can move through surface channels formed by regions of surface band bending to distances of tens of micrometers from the place where they originally appear at the surface.
The surface band bending for p-doped silicon is less than 30?meV, while acceptor-type defects cause significant and preparation-dependent band bending on n-doped samples.
Effect of annealing and light illumination on electrical and optical properties of undoped a-Si :H films were studied. The surface energy band bending is created by H20 adsorbats in order to compare the difference between annealing state and light illumination state. The results show that the density of gap state has been increased by light illumination.
UPS involving core level photoemission peaks (Ga 3d for GaAs and Si 2p for Si)is measured for the (111), (110), (111),and (001)surfaces of GaAs and Si using thelight from a helium lamp (21.2 eV and 40.8 eV) and from the Berlin synchrotron ra-diation source BESSY (108.6 eV),respectively.These surfaces are prepared by ion bo-mbardment and annealing on cylindrically shaped GaAs and Si crystals with [110] astheir axis.The GaAs cylinder is in addition prepared by molecular beam epitaxy yield-ing As-rich phases o...
According to the value of energy difference between Ga3d core level and the valence band maximum of GaAs precisely determined by Kraut et al., the position of Fermi level with respect to the valence band maximum at the surface and the surface band bending of clean GaAs(111) can be determined by measuring the exact binding energy of Ga3d level in the UPS experiment. The electron affinity of GaAs can also be obtained by measuring the work function from the threshold of secondary electron energy distribution i...