PLEASE PROVIDE FULL SOLUTION WITH REFRENCE Do some search an

PLEASE PROVIDE FULL SOLUTION WITH REFRENCE

Do some search and discuss the deep trench isolation (DTI) process. The discussion should include the steps and IC fabrication techniques used in the process, advantages and disadvantages.

Solution

DTI formation is performed after Shallow Trench Isolation (STI) formation.The deep trench in this technology is used to significantly increase the analog packing density by bringing devices adjacent to each other across the deep trench, so enabling shrinks ranging from 50% for medium-voltage analog to >80% for high-voltage analog components compared to the 0.35m SMOS7 technology.Photolithography and Etch process are performed on standard core CMOS tools used for advanced node such as 45nm technology and permit to achieve DTI with an aspect ratio higher than 1:25

advantage:

A deep trench isolation process provides very low leakage current, low temperature dependence and minimal space consumption

disadvantage:

Damage to the silicon semiconductor material in regions adjacent to the trench caused due to subsequent heat treatment of the wafer.

Weak point of isolation oxide formation at trench bottom.