shielding from substrate noise

[swathi0356]

how shielding is made from substrate noise.how the resistance of the substrate can be reduced.
thank you every one.

 

[vbhupendra]

place gnd lines on the two sides of the signal; forcing most of the e.f. lines emanating from the noisy lines to terminate on gnd rather on signal.

 

[muralikrishma]

guard ring is something that protects from substrate noise. In case of p substrate then put a p+ diffusion surrounding the active and connect it to VDD .

In case of N well,, put N+ guard ring surrounding the active and connect it to the Ground or lowest possible potential.


This protects the active from Substrate noise.

May be some more techniques also........

 

[YESH_23]

substrate resistence will be the same but another layer which is less resistive than substrate is connected to substrate and then tied on the other side to vdd or gnd

so that any noise i.e unwanted currents will flom from the substrate to vdd or gnd through the low resistive path known as gaurd ring

in this way sheilding is made from substrate noise

 

[BigBoss]

It's not essentially possible to reduce substrate intrinsic resistance but connection and via resistances.

Second, to reduce substarte noises (many type of noise I mean ) it's possible to use BNTAP that is inserted buried layers in substarte and to use BN rings around noisy circuits and also TRENCH layers to isolate the circuits. In fact all depends on your technolgy because some of them may not be available in your technolgy.

So, every specific problem has specific solution, so there is no universal solution here..

 

[swathi0356]

thank you to every one.