Carrier concentration and mobility of unintentionally doped InP layers, grown directly on Si using metalhyphen;organic vaporhyphen;phase epitaxy, have been studied. The formation of antiphase domains (APDs) was found to depend on annealing of the Si substrate in an AsH3flow prior to epitaxial growth. Dislocation densities determined by the wet chemical delineation technique were (8plusmn;1)times;107cmminus;3, seemingly uncorrelated to APDs in the layers. In addition to a shallow donor and a compensating acceptor, a deep donor was observed affecting the temperature dependence of the freehyphen;electron concentration between 77 and 300 K. The electron mobility in this temperature range could be described in terms of the scattering mechanisms which are dominant in homoepitaxial InP, namely, scattering due to polar optical phonons, to ionized impurities, and to space charges. Electron scattering due to either of these mechanisms was strongly influenced by the occurrence of antiphase boundaries (APBs). The spacehyphen;charge density as well as the degree of compensation of the epitaxial layers increases with the density of APBs. Degraded 300 K mobilities were obtained indicating the effect of local stress at the APB.
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