Keithley Series 2600 User Manual

A-53
APPENDIX A
Scripts
Rev1: JAC 6.26.2007
]]--
------------------ Keithley TSP Function ------------------
function FET_Thres_Search(vdssource, lowvgs, highvgs, targetid) --Configure SMUA to source
a user-defined voltage on
--the drain-source (Vds) while SMUB sources a voltage on --the gate-source (Vgs). VGS is
varied using a binary
--search algorithm between a maximum and minimum Vgs value, and the drain-source current
(Id) is measured.
--If measured value is outside the tolerance, search is performed again until the value
falls within the
--specified range or the iteration limit is reached.
--Returns measured Vds, Vth, and Id.
local l_k --binary search loop count variable
local l_k_max = 20 --Maximum loop counts
local l_vds_source = vdssource --vdssource value
local l_high_vgs = highvgs --Start Ib high limit
local l_low_vgs = lowvgs --Start Ib lo limit
local l_target_id = targetid --Target Ic for binary search
local l_nplc = 1
local l_vgs_source = 0--Gate-sourced voltage
local l_id_meas --Drain-source measured voltage
--Default values and level check
if (l_vds_source == nil) then --Use default value
l_vds_source = 0.5
end --if
if (l_low_vgs == nil) then --Use default value
l_low_vgs = 0.5
end --if
if (l_high_vgs == nil) then --Use default value
l_high_vgs = 1.1
end --if
if (l_target_id == nil) then --Use default value
l_target_id = 1e-6
end --if
smua.reset() --Reset SMU
smub.reset() --Reset SMU

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)