CHARGE INJECTION LOGIC

The charge injection transistor is a semiconductor device based on transfer of hot electrons between separately contacted conducting layers. The nature of hot-electron injection by the real-space transfer allows the implementation of novel circuit elements. In particular, we propose a multiterminal single-device structure that works as a functional element with three logic inputs X j (j=1,2,3) and one output equal to (X1∩X 2∩X3)∪(X̄1∩X̄ 2∩X̄3). This device, called the norand, can perform both as a nor(X1,X2) and as an and(X 1,X2) element, reprogrammable electrically by changing the X3 input. The operation of norand with logic gain is demonstrated experimentally by an equivalent circuit connection of discrete charge injection transistors implemented within InGaAs/InAlAs on InP technology.