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X model of an asymmetrical barrier, most probably in polycrystalline structures is proposed and analysed in order to explain the experimental variety of the temperature dependences of the Hall mobility in polycrystalline films of CdSe. The voltage drop across a crystallite itself was considered. The temperature dependence of Hall mobility is shown t o have an activation energy equal to the height of the intercrystalline barrier a t low temperatures, while a t high temperatures the activation energy depends on the qualities of the crystallites. The model suggested enables to explain the experimental temperature dependences of Hall mobility as well as the influence of photoexcitation in polycrystalline and epitaxial films presented in the present work, and also the experimental results of CdSe films obt'ained by other authors.Fur die Erklarung der Vielfalt der experimentellen Ergebnisse der Abhangigkeit der Hallbeweglichkeit von der Temperatur in polykristallinen CdSe-Schichten wird das Modell einer nicht*symmetrischen Pot.entialbarriere vorgeschlagen und diskutiert, I n diesem Modell wird die Volumenleitflhigkeit der Kristallite berucksichtigt. Es wird gezeigt, daB bei niedrigen Temperaturen die Temperaturabhangigkeit der effektiven Beweglichkeit eine Bktivierungsenergie besitzt, die der Barrierenhohe entspricht. Bei hoheren Temperaturen hangt die Aktivierungsenergie von den Eigenschaften der Kristallite und dem Material zwischen den Kristalliten ab. Es werden die theoret,ischen Abhangigkeiten dargestellt.Da,s vorgeschlagene Modell erklart gut die experimentellen Ergebnisse der Temperaturabhangigkeit der Hallbeweglichkeit und den EinfluD der Photoanregung in polylrristallinen und epitaxialen CdSe-Schichten.

Temperature dependence of Hall mobility in n‐type CdSe single crystals in TSC, thermal quenching of photoconductivity, and equilibrium regimes has been investigated. In the thermally stimulated regime the mobility is considerably larger than the one under equilibrium conditions and reaches the equilibrium value nonmonotonously with increasing temperature. In the case of thermal quenching of photoconductivity a rise of mobility has been observed. The equilibrium mobility for low resistivity samples (ϱ ≈︁10 Ω cm) decreases according to the law μ ∼ T −5/6, and increases exponentially for high resistivity samples (≈︁ 1010 Ω cm). The difficulties of determination of trap parameters by TSC method are discussed in case of strong variation of either mobility or life time due to the recharge of centres. A TSC method based on the mobility measurement in the TSC regime is proposed. The results obtained may be explained by scattering of carriers on clusters. A model explaining the experimentally observed mobility dependence on temperature in the TSC regime is suggested.

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