WELL OF SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A well of a semiconductor device is provided to reduce stand-by current caused by a logic part in a stand-by operation, and to prevent disturbance of dynamic random access memory(DRAM) cell data caused by charge injection of the logic part. CONSTITUTION: A field region and an active region are isolated by a field insulating layer in a semiconductor substrate(20) in which the first region and the second region are defined. A pair of the first and second conductive wells make a junction in the active region. The second conductive well for isolation is located between the adjacent first conductive wells. The first conductive well for isolation is formed in the first region. The second retrograde well is formed in a predetermined depth of the substrate, surrounding the first and second conductive wells at a position under the first and second conductive wells.