Buried channel charge coupled device with semi-insulating substrate

A charge coupled device comprising:

• a semi-insulating GaAs substrate having a resistivity of at least 10.sup.6 ohm centimeters;
• an n-type, semi-conducting GaAs charge transport layer having a thickness of less than about 5 .mu.m and covering only a portion of a surface of said substrate so that there is an interface on the surface of said device between said charge transport layer and said substrate;
• a row of parallel, closely spaced Schottky barrier gates on said charge transport layer, each of said gates overlapping said interface and being spaced from each other by a distance less than said thickness of said transport layer;
• input means for injecting a signal into said charge transport layer under one of said gates;
• and
• output means for detecting said signal from said charge transport layer.

A charge coupled device comprising:

• a substrate of a semi-insulating, semiconductor having a resistivity of at least 10.sup.6 ohm centimeters;
• a doped layer of said substrate forming a semi-conducting charge transport layer of a first conductivity type covering only a portion of a surface of said substrate so that there is an interface on the surface of said device between said charge transport layer and said substrate;
• a row of parallel, closely spaced Schottky barrier gates on said charge transport layer each of said gates overlapping said interface so that charges are confined within said charge transport layer without the need of a channel stop because of the resistivity of said substrate;
• input means for injecting a signal into said charge transport layer under one of said gates;
• and
• output means for detecting said signal from said charge transport layer.