A semiconductor device with gradients - band gap bete - znse ohmic contact for a ii - vi semiconductor

摘要

The present invention relates to semiconductor devices with ohmic contact to ZnSe-based layers and lasers derived therefrom wherein BeTe is used in a graded band gap layer. Preferably, an ohmic contact layer of BeTe-containing graded composition is used which consists essentially of Be.sub.x Zn.sub.1-x Te.sub.x Se.sub.1-x wherein x is within the range of 0 and 1 selected so as to provide substantial lattice matching to the lattice structure c the substrate. Specifically, Be.sub.x Zn.sub.1-x Te. sub.x Se.sub.1-x graded gap semiconductor layers are provided for application as ohmic contacts to p-type ZnSe, ZnS.sub.x Se. sub.1-x, Zn. sub.1-x Cd.sub.x S, Zn.sub.1-x Cd.sub.x S.sub.y Se.sub.1-y, Zn.sub.1-x Mg. sub.x S.sub.y Se.sub.1-y (wherein x and y are a number selected from 0 to 1) and other II-VI compound semiconductors used in lasers grown on GaAs substrates. Due to the close lattice match to GaAs substrate, graded (BeTe).sub.x (ZnSe).sub.1-x contact allow for the entire device structure to be grown within the pseudomorphic limit.