Variation of Electrical Properties with Zn Concentration in GaP

Abstract

The resistivity and Hall coefficient RH for Zn-doped GaP were measured at temperatures between 4.2° and 775°K. Neutron activation and through diffusion with radioactive 65Zn were used to determine the Zn concentration NZn, which ranged from 6.7×1016 cm−3 to 2.1×1019 cm−3. At the lowest Zn concentration the thermal ionization energy for Zn in GaP was found to be 0.060±0.002 eV. The thermal ionization energy decreases rapidly for Zn concentrations in excess of 2.0×1017 cm−3. Metallic impurity conduction was observed at a Zn concentration of 2.1×1019 cm−3. The low-concentration region is observed for NZn≲2.0×1017 cm−3, the intermediate-concentration region for 2.0×1017≲NZn≲2.1×1019 cm−3, and the high-concentration region for NZn≳2.1×1019 cm−3. In the intermediate-concentration region the high-temperature hole concentration, determined from p=1/eRH, was found to exceed the Zn concentration by a significant amount. Analysis of the temperature-dependent hole concentration results in an effective density-of-states mass ratio of approximately 0.5. The lightest doped sample had a room-temperature Hall mobility of 120 cm2/V·sec and a maximum mobility of 2050 cm2/V·sec at 55°K. The maximum mobility at low temperature is limited by ionized and neutral impurity scattering, while the dominant high-temperature scattering mechanism appears to be optical phonon scattering.

Conformal GaP layers on Si wire arrays for solar energy applications

“…These samples had typical mobilities of 300 cm 2 / V s and carrier concentrations of 8 ϫ 12 indicating that the presence of twins does not adversely affect carrier transport. The p-type mobility is lower than expected for single crystal GaP with a high acceptor density, 13 likely because of the structural disorder induced by changing the V/III ratio so drastically.…”

Impurity levels in layered semiconductor n‐InSe doped with Ge

“…The temperature dependence of µ I is calculated from The effective screening density n * is n + [(n + N a )(N dd + N ds -N a -n)/(N dd + N ds )] and the static dielectric constant ε is 10.6 [17]. The mobility µ N for neutral impurity scattering is given by Erginsoy as [19] µ N = {1.4 × 10…”

On the no‐phonon structure in mixed crystals with indirect band structure

“…Here the indirect exciton binding energy and the masses of the virtual crystal which appear in (3.14) were supposed to be weakly x-dependent, too. Thus the values of pure GaP were used (m, = 1 [7], m, = 0.5 [8], E , = 10 meV [9]). Further we have simplified the lineshape factor by assuming a: =at.…”