How addition of dummy transistors reduce Antenna Effect ?

[Sathishkrishna10]

Hi..

How the addition of dummy transistors reduce Antenna Effect ??

can anyone elaborate this ??

 

[yadavvlsi]

A transistor is used as diode to fix antenna. We can place a diode near the MOSFET and connect it to its gate in reverse biased manner, so that the diode will provide a conductive path to substrate, if the induced charge is above a limit.

https://www.evlsi.com/viewtopic.php?f=20&t=38

 

[Sathishkrishna10]

thank you Yadavvlsi.

i read that if we use dummy transistors to reduce Antenna Effect, "Reverse Antenna Effect" will occur.

What is Reverse Antenna Effect ?? How its differ from Antenna Effect ???

 

[D.A.(Tony)Stewart]

I realize there may be a large E-field in the plasma process and the gate impedance is high making it susceptible to breakdown.

However I believe the name "Antenna Effect" is a misnomer and better described as a "charge generator" effect and thus anti- means discharge.

 

[Sathishkrishna10]

A transistor is used as diode to fix antenna.

https://www.evlsi.com/viewtopic.php?f=20&t=38

why we go for "Transistor as diode" while we have actual diode. ????

 

[erikl]

why we go for "Transistor as diode" while we have actual diode. ????

E.g. in an array, where you have dummy transistors at the edges to keep a consistent environment for the inner active transistors. In such case you can use a dummy transistor as a gate diode against antenna violation. Otherwise a standard diode will do the job.