Films of CdTe were grown by focussed electron beam evaporation in vacua in the 10−5 to 10−6 Torr range on Ge substrates with (100), (110), and (111) surface orientations. For (100) substrates the epitaxial growth range of substrate temperature was 250 to 470°C, whereas for both (110) and (111) substrates it was 200 to 470°C. On (100) substrates the films grew with the cubic sphalerite structure in parallel orientation with the substrate. The diffraction patterns of these (100) films were streaked in the 〈111〉 directions indicating the presence of high densities of {111} planar defects. The films grown on (111) substrates had the hexagonal wurtzite structure in the epitaxial orientation relationship: (0001) CdTe parallel to (111) Ge with [1120] CdTe parallel to [110] Ge. The (0001) films grown at substrate temperatures throughout the epitaxial range had diffraction patterns that contained neither streaks nor satellite spots. Thus the films contained neither three dimensional defects such as included grains of second phase material nor planar defects in high densities. The films grown on (110) substrates had basically the sphalerite structure in parallel alignment. However, the diffraction patterns of (110) films grown throughout the epitaxial range were streaked in the two 〈111〉 directions at 35.3°C to [110] normal to the plane of the film. This was due to faulting on the two corresponding {111} planes in a striking domain‐form transformed structure.

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Intentional perturbations applied to the growth parameters of Sn-doped GaAs layers grown by molecular beam epitaxy have been performed in order to investigate the tin incorporation mechanism. The start, the interruption, and the end of growth as well as a variation of fluxes or substrate temperature have been studied, using either the Auger electron spectroscopy (AES) measurement of tin accumulation on the surface, or C-V derived free-carrier concentration profile versus any of these growth parameters. The theoretical model proposed by Wood and Joyce, based on a time-delayed incorporation mechanism, has been found to fit the observed results, especially for As-rich surface, provided that an incorporation mechanism of second order is assumed. For Ga-rich conditions (Ts≳580 °C), a new result has been recognized, i.e., a significant reduction of carrier concentration as Ts is increased. The assumption of a partially acceptor nature of tin incident atoms under these growth conditions does not seem to fully explain this result. On the other hand, this may be better understood assuming a certain amount of tin atoms being re-evaporated in the high substrate temperature range. This behavior induces a temporarily weaker accumulation at the surface, and hence a relatively smaller incorporation rate.

CdTe was evaporated on to (111) surfaces of Xi in an oil-pumped vacuum systcm in pressures in the Torr range. Reproducible epitaxial growth was obtained at all substrate temperatures in the range from 400 to 520 O C . Above this temperature no film could be deposited. The films had the wurtzite structure and the epitaxial orientation relationship was (0001) CdTe parallel to (111) Si with [llZO] CdTe parallel to [I101 Si. The films grown at temperatures in the range from 400 to 500 "C gave transmission electron diffraction patterns that were free of both satellite spots and streaks. This indicated that these films were free both of three-dimensional defects such as twirls and included grains of second phase material and of high densities of planar defects such a s stacking faults. The films grown a t temperatures above 500 "C gave diffraction patterns containing (lOi0) streaks due to faults on the prismatic planes { lOI0).Auf (111)-Oberflgchen von Si wurde in einem Olpumpen-Vakuumsystem bei Driicken im lo-' Tom-Bereich CdTe aufgedampft. Reproduzierbares Epitaxiewachstum wurde bei allen Substrattemperaturen im Bereich von 400 bis 520 "C erhalten. Oberhalb dieser Temperatur konnte keine Schicht aufgebracht werden. Die Schichten hatten Wurtzit-Struktur nnd die Epitaxie-Richtung war (0001) CdTe parallel zu (111) Si mit [llZO] CdTe parallel zu [ l i O ] Si. Schichten, die bei Temperaturen zwischen 400 und 500 "C gewachsen waren, ergaben Transmissions-Elektronenbeugungsdiagramme, die frei von Satellitenpunkten nnd -streifen waren. Dies zeigt, daB diese Schichten sowohl frei sind von drcidimensionalen Storungen, wie Zwillingsgrenzen und EinschluBgrenzen einer zweiten Phase, als auch von ebenen Defekten hoher Dichte, wie Stapelfehlern. Schichten, die oberhalb 500 "C gewachsen waren, ergaben Beugungediagramme mit (lOiO)-Streifen, hervorgerufen durch Stapelfehler auE den { lOI0}-PriamenfIachen,

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