Method for removing residual extrinsic impurities in an n type zno or znmgo substrate, for p-type doping of this substrate

Abstract

A method for purifying an n-type ZnO and/or ZnMgO substrate to reduce or eliminate the residual extrinsic impurities including introducing a reactive species having strong chemical affinity for at least one of the residual extrinsic impurities, and/or being capable of creating crystalline defects, is introduced in at least one region of the substrate, the reactive species being P, and whereby at least one getter region capable of trapping the said residual extrinsic impurities and/or in which the residual extrinsic impurities are trapped is created in the substrate; then annealing the substrate to cause diffusion of the residual extrinsic impurities towards the getter region and/or to outside the getter region. A method for preparing a p-doped ZnO and/or ZnMgO substrate comprising purifying an n-type ZnO and/or ZnMgO substrate using the above purification method in which one or more reactive species are used not limited to phosphorus alone.