Tetrode transistor

Early tetrode transistors

There were two types of tetrode transistor developed in the early 1950s as an improvement over the point-contact transistor and the later grown-junction transistor and alloy-junction transistor. Both offered much higher speed than earlier transistors.

• Point-contact transistor having two emitters. It became obsolete in the mid-1950s.
• Modified grown-junction transistor or alloy-junction transistor having two connections at opposite ends of the base.{{cite book

Modern tetrode transistors

• Dual-emitter transistor, used in two-input transistor–transistor logic gates
• Dual-collector transistor, used in two-output integrated injection logic gates
• Diffused planar silicon bipolar junction transistor, used in some integrated circuits. This transistor, apart from the three electrodes (emitter, base, and collector), has a fourth electrode or grid made of conducting material placed near the emitter-base junction from which it is insulated by a silica layer.
• Field-effect tetrode

References

References

1. {{US patent. 4143421 - ''Tetrode transistor memory logic cell'', March 6, 1979. Filed September 6, 1977.