Method of growing quaternary or pentanary compound semiconductor by MBE lattice-matched to substrate

摘要

III-V group multinary alloy semiconductors such as ternary, quaternary, and pentanary semiconductors grown on a binary III-V compound semiconductor substrate, are used as an active layer in opto-devices, high electron mobility transistors, and the like. As a method of growing multinary layers, lattice-matched to the binary substrate and having specified specified energy band gaps, MBE is an effective means therefor. The present invention discloses the method of growing quaternary or pentanary layer using minimum number of effusion cells and eliminating readjustment of molecular beam intensities from one layer to another layer thereon in a series of epitaxial growth. As an example of quarternary growth, only four effusion cells are utilized and two combinations of three effusion cells are alternatively operated, one including Al cell and the other, Ga cell, and all three effusion cells being capable of growing a ternary semiconductor lattice-matched to the substrate. Two groups of pulsed molecular beams, each pulse having a width of growth time less than three atomic layers, can grow a quaternary alloy semiconductor also lattice-matched to the substrate. Similarly, a method of growing a pentanary alloy semiconductor utilizing five effusion cells in MBE system is disclosed.