Application of grown oxide bumper insulators to a high-speed VLSI SASMESFET

A high speed Schottky barrier field effect transistor, with low series resistance, comprising:

• a substrate of one conductivity type;
• a source region heavily doped to the other conductivity type;
• a drain region heavily doped to the other conductivity type;
• a channel region separating said source region and said drain region;
• Schottky barrier gate means forming a rectifying junction with a portion of said channel, said gate means providing, when properly biased, control of the current flow between said source region and said drain region;
• and
• an oxide layer with (1) first portions thereof covering portions of the external surface of said source and drain regions and (2) other portions thereof covering the portions of said channel between said source region and said barrier gate and between said drain region and said barrier gate, cross-sections of said other portions of said oxide layer being generally curved with height and thickness dimensions greater than the thickness of said first portions of said oxide layer due to favored oxide growth at the edges of said barrier gate, whereby source-to-gate and gate-to-drain resistances are low which permit the transistor to operate at high frequencies.

A high speed Schottky barrier field effect transistor, with low series resistance, comprising:

• a substrate of one conductivity type;
• a source region heavily doped to the other conductivity type;
• a drain region heavily doped to the other conductivity type;
• a channel region separating said source region and said drain region;
• Schottky barrier gate means forming a rectifying junction with a portion of said channel, said gate means providing, when properly biased, control of the current flow between said source region and said drain region;
• and
• an oxide layer with (1) first portions thereof covering portions of the external surfaces of said source and drain regions and (2) other portions thereof covering the portions of said channel between said source region and said barrier gate and between said drain region and said barrier gate, cross-sections of said other portions of said oxide layer being generally circular with height and thickness dimensions greater than the thickness of said first portions of said oxide layer due to favored oxide growth at the edges of said barrier gate, whereby source-to-gate and gate-to-drain resistances are low which permit the transistor to operate at high frequencies.