PROCESS FOR PRODUCING SOI SUPER JUNCTION LDMOS STRUCTURE COMPLETELY ELIMINATING EFFECT OF SUBSTRATE ASSISTED DEPLETION

摘要

A process for producing a silicon on silicon (SOI) super junction lateral double-diffused MOSFET (LDMOS) structure completely eliminating the effect of substrate assisted depletion comprises the following steps: making a conductive layer (10) under a buried oxide layer (9) by using a bonding process; making the super junction LDMOS structure on the SOI substrate having the conductive layer (10). The detailed production process of the conductive layer (10) comprises: depositing a barrier layer on the first bulk silicon wafer, and then depositing a charge guide layer to obtain the first intermediate structure; thermally oxidating the second bulk silicon wafer to form a silicon oxide layer, and then depositing a barrier layer, and finally depositing a charge guide layer to obtain the second intermediate structure; bonding the first intermediate structure to the second intermediate structure by a metal bonding technique to form the conductive layer (10) under the SOI buried oxide layer (9). The present invention can release charge accumulated at the low interface of the buried oxide layer (9) and eliminate influence of the longitudinal electric field on charge balance of a p/n pillar area, to completely eliminate the effect of substrate assisted depletion and improve the breakdown voltage of device.