The MOS capacitor ( we used Al for metal,silicon for semiconductor)which we built can work until Mhz frequencies.Why do not we get capacitance at Ghz frequencies?
2006-11-24 00:41:51 · 3 answers · asked by seawave 2 in Science & Mathematics ➔ Physics
Actually,my teacher said me that all of the MOS capacitors can work until Mhz limit.It is not related to our silicon sample.But in technology,we can achieve info until Ghz limit.How this happens?
2006-11-24 23:45:00 · update #1
It probably is still providing capacitive reactance, but it's getting swamped by some other circuit component such as resistance (caused by skin effect) or inductance. Both of those (and several others) are functions of frequency,
Doug
2006-11-24 00:48:50 · answer #1 · answered by doug_donaghue 7 · 0⤊ 0⤋
The usual problem is lead inductance. Shorten them if you can.
The Al may be acting as a waveguide at these high frequencies.
How pure is your Si. Do you have a resonance frequency in it due to dopants?
2006-11-24 15:53:39 · answer #2 · answered by Rufus Cat 3 · 0⤊ 0⤋
If I had paid attention in class last semester, maybe I could have answered this...
:-(
2006-11-24 09:30:56 · answer #3 · answered by Anonymous · 0⤊ 0⤋