| Lead telluride is the best known member ofⅣ-Ⅵsemiconductor compounds and alloys. By HWE(Hot Wall Epitaxy), PbTe films were grown, respectively, on the Si substrate and diamond substrate. X ray diffraction, scanning electron microspectrum, electron basic scatter diffraction and X photoelectron spectrum were used to study microstructure, electric property and mechanism.PbTe(100) film grown on Si(111)7×7substrate is actually twinned when the temperature of substrate and source is 400 oC and 520 oC, respectively. XRD shows that PbTe facet parallel to the surface of Si (111) substrate. the 30o or 60o twinned is observed by EBSD, the same result with XRD can be concluded by the normal pole of EBSD and it is clear that the films consist of domains rotated by 30o or 60o around the normal to the Si(111) surface with the PbTe(1 0 0) planes parallel to the Si(111) planes. The [11-2] axis of rolling direction of Si substrate is parallel to the [001] axis of rolling direction of PbTe grains by the software analysis of EBSD. All these results are in accordance with theory approximate calculation. The pn junction of p-Si and n-PbTe exhibites non-linear and rectifying characteristics of diode. Ideality junction factor is investigated with different biaos, and high recombination rate of carriers result in the different ideality junction factor. The diagram of energy bind offset is painted by calculating the valence offset. Then the reason affecting magnitude of sharp peak is discussed. It is concluded that the character of p-Si/n-PbTe heterojunction can be improved by controlling the magnitude and position of sharp peak.For undoped PbTe evaporation source, triangle nucleuses and square nucleuses coexisted on the sample when the temperature of evaporation source was at 520 oC, and the temperature of substrate was decreased to 340 oC. But in this work, Bi-doped PbTe source instead of undoped PbTe evaporation source. only triangle nucl euses can be seen with the growth condition away from thermal equilibrium。This is attributed to the fact that Bi dopants impel PbTe to grow along <1 1 1> direction. the growth Abstract velocity of PbTe crystalline surface are changed by Bi dopants and based on the theory that the surfaces with the fastest growth rate will shrink or not be present in the final crystal shape. As a result, only triangle nucleuses present. This result is consistent with that of Micro area X-ray diffraction. By the analysis of EBSD software, the films were consisted of two domains, one of them was rotated 60o or 180o around the normal to the film surface. Atoms arrangement of triangle-shaped PbTe grains and growth mechanism were discussed.The growth of n-PbTe films on the p-diamond substrate is tried. The PbTe films are grown on the diamond substrate, successfully, when the temperatures of substrate and source are 340 oC and 520 oC, respectively. Considering the merit of diamond and characteristic of infrared detector, the virtue of heterojunction as infrared detector is discussed. The strains exist in the film from XRD data. The pn junction of p-diamond and n-PbTe is grown from the I-V curve, exhibiting rectifying characteristics of diode. The diagram of energy bind offset is painted by calculating the valence offset. Then the magnitude of valence offset is calculated and the reason affecting magnitude of sharp peak is discussed. It is concluded that the character of p-Si/n-PbTe heterojunction can be improved by controlling the doped concentration.
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