GRADED COMPOSITION OHMIC CONTACT FOR P-TYPE II-VI SEMICONDUCTORS

摘要

A II-VI laser diode including a substrate, a device layer of p-type II-VI semiconductor, and electrode and an ohmic contact layer between the electrode and device layer. The ohmic contact layer comprises a graded composition semiconductor compound including ZnTe. The relative amount of ZnTe in the semiconductor compound increases with increasing distance of the ohmic contact layer from the device layer. In a first embodiment the ohmic contact layer comprises a graded composition semiconductor alloy including the semiconductor compound of the device layer and ZnTe. The amount of ZnTe in the alloy increases with increasing distance of the ohmic contact layer from the device layer in the first embodiment. In a second embodiment the ohmic contact layer includes layers of ZnTe spaced between layers of the semiconductor compound of the device layer. The thickness of the layers of ZnTe increases, or the thickness of the layers of the semiconductor compound of the device layer decreases, with increasing distance of the ohmic contact layer from the device layer in the second embodiment.