Search Engine www.edaboard.com

Nmos Substrate Contact

Add Question

15 Threads found on edaboard.com: Nmos Substrate Contact
hello, i'm new with analog design with this pack of ibm and i have a trouble that i can't solve. I'm doing a simple inverter with Mentor Graphics in this technology and in the schematic i put the subc for the nmos, but i don't have a contact for the substrate of the PMOS, and when i do the DRC, this is an error message that shows up, i (...)
The nmos transistors all share the same p-substrate. So you have to connect the bulk connection of the upper nmos to the p-substrate, too, not to its source. The nmos' bulk is identical to the p-substrate. Just add a P+ contact area next or adjacent to the N+ source, and (...)
In cheap CMOS technologies the handle is usually P- (so nmos needs no well and the substrate can be tied to ground / VSS). A lot of things follow from that choice. But that choice is not necessarily -the- choice, putting your premise in question somewhat. Your buried layer is only an ohmic contact extension of the collector, which lies at (...)
So, what happens when the source/bulk of the nmos transistor is biased positively? Will the bulk/body voltage rise, due to a current injection (majority carriers - holes) into the substrate, that will be picked up (extracted from the substrate) by the neighboring p+ contacts / guard rings? Do you want to account for that (...)
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
I think it's the same as substrate TAPPING, i.e. providing low-ohmic connections from the substrate via a p+ region (in case of a p- substrate), contact to Metal_1 and a fully metal wire connection to GND (gnd!), not too far from all nmos sources (these are the necessary nmos body connections).
I was implemented nand gate layout in cadence it correct or not... one body (M1_pDiff for nmos,M1_Nwell for PMOS) is enough for all nmos(pmos) circuits in the design... how to connect the substrate.... IN schematic all nmos body connect to the gnd,all pmos connect to the supply vdd.... just i am in starting stage.. lay
you need to add substrate contact in the layout. add an instance of subc in layout and connect it to the source of nmos. in schematic, the top of subc is connected to source, the bottom is connected to bulk.
Is it recommended in 90nm cmos to put a guard ring around each device? or just around ALL pmos(Nmoat connected to VDD) then around ALL nmos(pmoat connected to Vss). No. You need not put guard ring around every device....however for some critical transisitors it might have to.. Also what about
Hello! I'm design RF passive ring MOSFET mixer on nmos. I'm confused where to connect substrate contact? Maybe leave it open...
The layout program must be virtuoso, & right green area should be nwell region. In virtuoso, the black background is substrate. If you use p-substrate process, then all background (black) area is p-sub. And now, in nmos case, there must be p+ region for sub-tie. So you can draw p+ diffusion & contact at p-sub near (...)
Hi, Any DRC will check as per the minimum distances and minimum dimensions to be followed for DRC Clean. Thus with error "nmos to pwell contact max 30um"..... which states that the distance between the nmos device and a substrate Pwell contact must not exceed 30um and place them close to each other. (...)
Dear all, What is a typical value for the resistance of the substrate connection of each MOS in a 0.35 CMOS process? I am talking about the effective resistance that, for instance, the bulk terminal of an nmos will see to the ground line, when directly connected to it (like the typical nmos with source and bulk tied to ground that are (...)
Hi, The merits that you can get in this kind of layout style are: * good isolation for both devices nmos/pmos. * you avoid latch-up problem demerit: * chip real estate issue * added parasitic resistance/capacitance ;-)
AA is probably active area - it just means that there is no thick field oxide (FOX) so you can make contact with the diffusion. You need AA cuts wherever there is a transistor. As for PMOS/nmos, are you sure you're not missing a well somewhere? In an N-well process, the nmos are made directly in the sea of substrate, (...)