METHOD FOR MANUFACTURING CMOS IMAGE SENSOR IMPROVING RESET EFFICIENCY BY CONTROLLING THRESHOLD VOLTAGE AND BREAKDOWN VOLTAGE OF RESET TRANSISTOR

摘要

PURPOSE: A method for manufacturing a CMOS image sensor is provided to improve reset efficiency by controlling the threshold voltage and breakdown voltage of a reset transistor. CONSTITUTION: A p-type epi layer(31) is formed in a p-type substrate(30) defined in a reset transistor region. The epi layer is surrounded by an n-well barrier layer(32). P-type impurity ions are implanted into the epi layer in order to control the breakdown voltage. A gate insulating layer(33), a gate(34) of a reset transistor and a spacer(35) are sequentially formed on the epi layer. A source(36A) and a drain(36B) are formed in the epi layer. A p-type pick-up region(37) is formed in the epi layer and spaced apart from the drain. The pick-up region is connected with the gate of the reset transistor.