BIPOLAR-CMOS-DMOS DEVICE AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A method for fabricating a Bipolar-CMOS-DMOS(BCD) device is provided to fabricate a BCD device that has voltage tolerance of 20-30 volt and 60-90 volt and gate oxide layers of different thicknesses by using a CMOS device process of a submicron class. CONSTITUTION: Only a drift region is formed under a drain region of a lateral double diffused MOS(LDMOS) device of 20-30 volt class while a drift region is formed under a drain region of 60-90 volt class so that a well region is formed to improve voltage tolerance and an on-resistance characteristic. A gate oxide layer of an nLDMOS device is made thin while a gate oxide layer of a pLDMOS device is made thick so that a gate apply voltage is increased to improve driving capability. A device occupying area is reduced by isolating devices while using a trench. A drift region of a DMOS device is formed to simplify a process by using a mask for forming the base of a bipolar device.