Hi I've found this article, describing how to form the titanium silicide: http://ic-garden.cn/?p=829
I think I will adapt this into our process.
Cheers David
On Thursday, 8 March 2018 4:19:31 PM HKT David Lanzendörfer wrote:
Hi
But I think the silicide was also used as stopping layer for the contact hole etch. Can you etch the contact holes without the silicide? Due to the big depth difference between the gate contacts and the source/drain contacts you need a good stopping layer otherwise you will just etch through the polysilicon.
We can use BHF method, which selectively only etches oxide but nothing else. http://www.nff.ust.hk/en/equipment-and-process/equipment-list/dry-etching-a nd-sputtering-module.html 6HF reacts with SiO2 into H2SiF6+H2O The polysilicon isn't oxidized, so there is no basis for a reaction, the oxygen atoms are missing.
With the "AOE Etcher (DRY-AOE)" from HKUST we can selectively etch the contact windows into the oxide, without putting too much stress at the polysilicon.
I guess this will work, but we will have to try it out.
Cheers David
On Thursday, 8 March 2018 4:42:12 AM HKT Staf Verhaegen wrote:
David Lanzendörfer schreef op wo 07-03-2018 om 22:47 [+0800]:
-> Do we need to fight with silicides from the beginning or can we just start with polysilicon in order to get something "kindof working"?
My expertise was in lithography so for me silicidation was a step done by other groups. So I don't know the details of the process. But I think the silicide was also used as stopping layer for the contact hole etch. Can you etch the contact holes without the silicide? Due to the big depth difference between the gate contacts and the source/drain contacts you need a good stopping layer otherwise you will just etch through the polysilicon.
-> Do you know someone who has experience with the step of producing silicides and polisilides for reducing the gate-resisitivity?
The environment was a classic work environment and I don't remember any open source sentiment from the time there. The people I knew there have either moved on in the management ladder or to other things. I think it is best to try to socialize with experts from the Hong Kong fab where you will do the processing.
greets, Staf.