Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

thin oxide cover substrate contact

Status
Not open for further replies.

fanshuo

Full Member level 5
Joined
Jun 21, 2007
Messages
266
Helped
8
Reputation
16
Reaction score
4
Trophy points
1,298
Location
Netherlands
Activity points
2,748
I was asked to cover the substrate contact with thin oxide which also cover the body of transistor
anybody know why to do it?

ThX
 

yadavvlsi

Advanced Member level 3
Joined
Nov 19, 2010
Messages
978
Helped
485
Reputation
968
Reaction score
454
Trophy points
1,343
Location
Bangalore, India
Activity points
6,991
Top oxide layer dopped with phosphorus commonly known as P-Glass is used as device passivation layer. This protect device from corrosion.
 

erikl

Super Moderator
Staff member
Joined
Sep 9, 2008
Messages
8,112
Helped
2,689
Reputation
5,358
Reaction score
2,289
Trophy points
1,393
Location
Germany
Activity points
44,153
I was asked to cover the substrate contact with thin oxide which also cover the body of transistor
Thin oxide = gate oxide is exclusively to be used for the gates. Substrate contact = NMOS body contact needs metal1 over it. Any oxide between would prevent the contact.
 

dick_freebird

Advanced Member level 5
Joined
Mar 4, 2008
Messages
7,120
Helped
2,087
Reputation
4,178
Reaction score
1,932
Trophy points
1,393
Location
USA
Activity points
57,125
Active (thin ox) is also a hard mask (along w/ poly) for N+/P+ implant.
 

dgnani

Advanced Member level 1
Joined
Jul 25, 2009
Messages
425
Helped
160
Reputation
322
Reaction score
152
Trophy points
1,323
Location
USA
Activity points
4,007
I was asked to cover the substrate contact with thin oxide which also cover the body of transistor
anybody know why to do it?

ThX
Are you talking about drawn layers in a layout tools or something else?

If so, is 'thin oxide' the name of the layer or is the layer used something called 'RX' or "ACT' or 'DIFF'?
 

fanshuo

Full Member level 5
Joined
Jun 21, 2007
Messages
266
Helped
8
Reputation
16
Reaction score
4
Trophy points
1,298
Location
Netherlands
Activity points
2,748
what I mean is when doing layout
you have the layer called thinox(thin oxide)

you will found it cover the body of NMOS/PMOS

why should I cover the NMOS/PMOS together with its body contact with one thinox?
what is the advange
 

dick_freebird

Advanced Member level 5
Joined
Mar 4, 2008
Messages
7,120
Helped
2,087
Reputation
4,178
Reaction score
1,932
Trophy points
1,393
Location
USA
Activity points
57,125
You get to save several overlaps and spacings if you use a common
active (tox) region. Lay out two versions, and see.
 

dgnani

Advanced Member level 1
Joined
Jul 25, 2009
Messages
425
Helped
160
Reputation
322
Reaction score
152
Trophy points
1,323
Location
USA
Activity points
4,007
what I mean is when doing layout
you have the layer called thinox(thin oxide)

you will found it cover the body of NMOS/PMOS

why should I cover the NMOS/PMOS together with its body contact with one thinox?
what is the advange
what do you mean by "body of NMOS/PMOS": the whole FET (including gate, source and drain) or the body/bulk contact?

I have gone through a few foundries by now and this is a first, who are you using?

since this problem is very specific to your foundry/PDK, you should probably describe which layers you had to use to build your FETs (an NMOS would suffice) so we can understand if your thinox layer is just a thinox layer (a layer that most foundries do not use - usually only the thick oxide layers are used and every FET not using thick oxide is assumed thin) OR if it is an RX/Diffusion layer which is used by most foundries and has multiple purposes
 
Last edited:

dalraist

Junior Member level 2
Joined
Sep 18, 2008
Messages
22
Helped
5
Reputation
10
Reaction score
0
Trophy points
1,281
Activity points
1,403
There is no reason to cover body contacts with Oxide layers.
As already stated, the layer affected by Thin/Med/Thick layers is Poly only.
If you have dataprep manual you can easily double check.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top