Need nfo on Antenna Effect in Layout?

Hi ,

Could anybody help me providing docs or info on this topic
like what is the antenna effect? how it arises, and what is the approach for avoiding it

Thanks for your support
Kiran Kumar

As far as I know,Antenna Effect happens when you make a poly layer of a too much area.Because during some subsequential process the larger poly will collect more electron(behaves somewhat like an antenna).If the excessive electron lead to a gate voltage exceeds the breakthrough voltage,it will damage the device.
So to avoid the antanna effect,you should avoid large poly area.And if you have to make a big transistor,you can split the gate and connect them with metal layers.
Hope this will help.

antena effect happen if your poly connect to long metal wire. so avoid connecting gate with long metal wire. You can use jumper to prevent antenna effect if you need to connect gate to long metal wire.

DZC's explanation is very clear!

Antenna effect can happen for any large interconnect(not only poly)connected to the gate of a transistor.Because the large metal area can accumulate charges during etching and will find a way to dissipate after that layer is processed.That charge might be too much for the thin gate to handle and may damage it.

With regards to gate, antenna effect on the gate occurs when the poly is "edge intensive" ... meaning the poly lines used results in a lot of edges on the device due to STI (shallow trench). When this happens, there's a more electric field seen around the poly and so the charge deposited causes the oxide to start to breakdown (read about hole traps and electron traps). Also, because there's more surface area, the poly is collecting more plasma ions that contribute to amount of charge on it.

Antennas are used in designing test structures, just how the poly is able to collect plasma, so it is with other layers ... especially metals. When metal1 is designed in antenna form, it results in shallow trenches formed around the metal1 structure and so more electric field and more charge.

See **broken link removed** link.