Keithley Series 2600 User Manual

A-48
APPENDIX A
Scripts
Program 10. Transconductance
--[[
Transconductance():
This program sources a voltage bias on a drain-source of a FET (VDS), sources a voltage on
the gate (VGS1), and measures the drain-source current (ID1). Then, another source value
(VGS2) is sourced and the IDS2 is measured.
The transconductance (gfs) is then calculated by taking the change in Ids divided by the
change in VGS.
The drain-source voltage (VDS), Transconductance (gfs), gate-source voltage (VGS), and
drain-source current (ID) are returned.
Required equipment:
(1) Dual-channel Keithley Series 2600 System SourceMeter instrument
(1) SD210 N-channel FET
Running this script creates functions that can be used to create a transconductance test
of FETs. The default values are for an N-channel SD210 FET.
The functions created are:
1. Transconductance(vgsstart, vgsstop, vgssteps, vdsbias)
--Default values vgsstart = 0V, vgsstop = 5V, vgssteps = 100, vdsbias =
10V
2. Check_Comp()
See detailed information listed in individual functions.
To run:
1) From Test Script Builder
- Right-click in the program window, select “Run as TSP”
- At the TSP> prompt in the Instrument Control Panel, type Transconductance()
2) From an external program
- Send the entire program text as a string using standard GPIB Write calls.
Rev1: JAC 6.18.2007
]]--
------------------ Keithley TSP Function ------------------
function Transconductance(vgsstart, vgsstop, vgssteps, vdsbias)--Configure SMUA to source a
user-defined voltage on the

Keithley Series 2600 Specifications

General

Model	Series 2600
Measurement Functions	Voltage, Current, Resistance, Power
Resolution	Up to 6.5 digits
Current Source Range	Up to 10A
Communication Interfaces	GPIB, USB
Applications	Semiconductor testing
Category	Source Measure Unit (SMU)
Channels	Single or Dual Channel (varies by model)