FET eDRAM TRENCH SELF-ALIGNED TO BURIED STRAP

摘要

A structure and method of making a field effect transistor (FET) embedded dynamic random access memory (eDRAM) cell array, which includes: a buried silicon strap extending into a buried oxide (BOX) layer of a silicon-on-insulator (SOI) substrate; a recessed trench capacitor extending down into the substrate layer of the SOI substrate; a lateral surface of a conductive top plate formed on the recessed trench capacitor that contacts a first lateral surface of the buried silicon strap; a dielectric cap disposed above the conductive top plate; a first FET formed from the silicon layer of the SOI substrate, in which a source/drain region of the first FET contacts a second lateral surface of the buried silicon strap; and a passing wordline disposed on a portion of the dielectric cap opposite to and separate from the buried silicon strap and connected to a gate of a second FET in an adjacent row of the FET eDRAM cell array.