What is the reason for using thick oxide?

[siddharth1501]

why we use thick oxide? only for breakdown protection or any other reason?

 

[erikl]

Re: oxide breakdown

Silicon(di)oxide is quartz glass, and

• can be thermally grown on silicon
• is chemically very resistant
• protects the silicon below from environmental influences (it is tight)
• acts well as diffusion or implant mask
• ... and has a relatively high electrical breakdown field strength

For more info, search for **broken link removed**.

 

[dick_freebird]

oxide breakdown

If you mean the thicker gate in a dual gate process, it's simply
for rated-voltage reliability (breakdown is higher than reliable Vox
working voltage).

In almost every other respect the thick gate ox device will be
inferior. But there's plenty of jobs in this world for big and dumb.