- #1
Erikve
- 18
- 0
Dear all,
I measured some very nice data, but it's difficult to analyze, but I try to get out of it what I can. I have diverging resistance and did measure with standard lock-teqnique: apply 0.45V over preresistor and send current over sample and measure the two-probe resistance over the same contacts as where I send the current.
At the moment that the sample reaches the border of 10MOhm we get of course problems since current starts leaking away via the 100MOhm input-impedance of the lock-in and the capacitor of 25pF. I measured the current with a second lock-in. With this data I should be able to extract still quite the resistances up to 1 GOhm, but somehow I cannot find the right way how to deal with this.
Somebody who can help me out of the spaghetti of electrical circuits?
Thanks you.
I measured some very nice data, but it's difficult to analyze, but I try to get out of it what I can. I have diverging resistance and did measure with standard lock-teqnique: apply 0.45V over preresistor and send current over sample and measure the two-probe resistance over the same contacts as where I send the current.
At the moment that the sample reaches the border of 10MOhm we get of course problems since current starts leaking away via the 100MOhm input-impedance of the lock-in and the capacitor of 25pF. I measured the current with a second lock-in. With this data I should be able to extract still quite the resistances up to 1 GOhm, but somehow I cannot find the right way how to deal with this.
Somebody who can help me out of the spaghetti of electrical circuits?
Thanks you.