how to improve the data resolution by using Keithley 2400

[echhoo]

Hi,

I'm trying using Keithley 2400 to measure I-V curve, but when the current down to 1.0E-7 A, the noise is very high. Because I used a Labview VI which I found in the forum, but I don't know wheter the data resolution can be affect or not by using this VI, such as the setting value of this VI. I measured a resistor(20k Ohm), I wander if it's possible to get the current at the level of nA? Of course the connection between resistor and cable may cause some nosie, now I hope someone can tell me how can I improve the setting of this VI and get higher resolution dada. Thanks, the attachment is the VI and data I got.

[nitad54448]

hi

first you must check that the 2400 (from memory, a source meter) has the ability to be stable at nA level. If so, here are some ways :

- check cable connections

-inverse current to cancel the thermocouple effects

- make sure you don't have coaxial cable effects

- check for field interference

-read the data measurement handbook published freely by Keithley

regards

N

[muks]

Continue here

Message Edited by muks on 10-14-2009 05:22 PM