DYNAMIC RANDOM ACCESS MEMORY DEVICE AND MANUFACTURE OF MULTIWELL TRANSISTOR THERE FOR

摘要

PURPOSE: To use different bias voltages among devices with different sizes. CONSTITUTION: A dynamic random access memory device 10 has three separate parts, namely an input/output part 12, a peripheral transistor part 14, and a memory array part 16, and all these parts are formed on a p-type substrate layer 18. The dynamic random access memory device 10 can use a separate substrate bias voltage for each part.