A programmable and erasable digital switch device is provided. An N-type memory transistor and a P-type memory transistor are formed over a substrate. The N-type memory transistor includes a first N-type doped region, a second N-type doped region, a first charge storage layer and a first control gate. The P-type memory transistor includes a first P-type doped region, a second P-type doped region, a second charge storage layer and a second control gate. A common bit line doped region is formed between the N-type memory transistor and the P type memory transistor and electrically connects the first N-type region to the second P-type doped region. A word line electrically connects the first control gate to the second control gate.