# Doping Dependence of Semiconductor-Metal Transition in InP at High Pressures

Bose, DN and Seishu, B and Parthasarathy, G and Gopal, ESR (1986) Doping Dependence of Semiconductor-Metal Transition in InP at High Pressures. In: Proceedings of the Royal Society A: Mathematical, Physical & Engineering Sciences, 405 (1829). pp. 345-353.

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## Abstract

The resistivity of selenium-doped n-InP single crystal layers grown by liquid-phase epitaxy with electron concentrations varying from 6.7 x 10$^18$ to 1.8 x 10$^20$ cm$^{-3}$ has been measured as a function of hydrostatic pressure up to 10 GPa. Semiconductor-metal transitions were observed in each case with a change in resistivity by two to three orders of magnitude. The transition pressure p$_c$ decreased monotonically from 7.24 to 5.90 GPa with increasing doping concentration n according to the relation $p_c = p_o [1 - k(n/n_m)^a]$, where n$_m$ is the concentration (per cubic centimetre) of phosphorus donor sites in InP atoms, p$_o$ is the transition pressure at low doping concentrations, k is a constant and $\alpha$ is an exponent found experimentally to be 0.637. The decrease in p$_c$ is considered to be due to increasing internal stress developed at high concentrations of ionized donors. The high-pressure metallic phase had a resistivity (2.02-6.47) x 10$^{-7}$ $\Omega$ cm, with a positive temperature coefficient dependent on doping.

Item Type: Journal Article Copyright of this article belongs to The Royal Society. Division of Physical & Mathematical Sciences > Physics 04 Aug 2009 03:05 19 Sep 2010 05:39 http://eprints.iisc.ernet.in/id/eprint/21779