ANTENNA VIOLATION QUESTION

[vlsitechnology]

In Antenna Violation...

What happens if we place the diode far from the gate? and what happens if we place the diode closer to gate? How these charges gets bypassed?? Any answer??

 

[santuvlsi]

dear Vlsi Technology,

If u palce diode near the gate . the lenght between gate and diode is less the maximum length will be between diode and floating end hence maximum charge will accumalate betweeen this terminals and will get dischagred thro doide. after discharging the remaining charge will not will be not sufficient to damage the gate.

if the diode is kept far from gate, in the length of wire that is between gate and diode is more and hence more charge accomadates , which will be more than Vt of gate hence gate will get damaged.

 

[vlsitechnology]

which is the floating end? and how it will be more than vt of the gate?

 

[santuvlsi]

Dear vlsi technology,

consider metal1 , consider a net passing in metal1,

let one end of the net is connected to gate of the transistor the other end must be connected to either source or diffusion they twomust be connected thro metal1.

gate is the receiver and drain/source is diver . so there must be a connection between driver and receiver

now consider one end of the net is connected to gate , if metal1 is not yet still deposited means process is going on , the other end of net which has to connected to the diffusion thro metal1 but will not find metal1 since its under deposition.

so this net is left as floating. during etching a process of depostion this floating net will get enough charge accumalation, to break down the gate. this is antenna effect.

hope u understood

if not get back

 

[venkat_kvr]

chk this this have good explanation about Antenna Violation