Electronic properties of crystallized glow discharge silicon

Abstract

The crystallization of doped and undoped specimens of amorphous silicon (a-Si) prepared by the glow-discharge technique has been investigated. At a heating rate of 1.5°C/min the onset of crystallization occurs near 620°C in undoped specimens, but phosphorus doping can reduce this value appreciably. Hall effect measurements show that conversion to the polycrystalline form removes the anomaly in sign found in amorphous n- and p-type specimens. The density of donors deduced from these measurements on crystallized specimens is approximately equal to the density of phosphorus atoms originally incorporated in the a-phase, suggesting that crystallization is a useful method for determining this quantity. Thermoelectric power measurements on crystallized n-type specimens can be interpreted in terms of the well-established crystalline theory, with impurity scattering as the predominant scattering mechanism.