Characterization Lab Policy

M. A. Alam

April 24, 2012

Probe station Usage: Introductory Comments

• If you are not a member of Alam group, you are a guest user. You are welcome, but only if you can be a responsible user.

• The purpose of the Characterization Lab is high precision,

long-term, well-calibrated measurements. There are other probe stations for simpler measurements. Therefore, this setup should used only if you cannot do measurement anywhere else.

• It is possible to share the system efficiently, but only if everyone behaves with highest professional integrity.

A generic probe station setup

TemperatureController

SMU-1

SMU-2

SMU-3

GNDU

PulseGenerator

CV

Oscilloscope

SwitchMatrix

CONTROLLER

(Computer)

IEEE 488 GPIB Bus

A

BC D

E G,H

12345

The Probe Station

InstrumentsComputer front-end / SMU (1-3):

Keithley 4200 SCSSwitch Matrix:

Keithley 7174ACV Measurement:Keithley 590

Quasistatic CV Measurement:Keithley 595

Voltage Source:Keithley 230

Function Generator:Agilent 33220A

Temperature controller:Temptronic TP0315B

Digital Oscilloscopes:Tektronix TDS5032B

Probe station policyGeneral Guidelines

• Before using the probe station, check for these errors, and report them immediately with details of previous user:– Broken probe-tips / all probe-tips not visible through microscope / insufficient

clearance.– Incorrect wiring.– Probe-station lamp turned on.– Hot chuck.– Any other form of damage.

• Any damage caused during probe station usage need to be reported immediately.

• You / your group is responsible for damaged probe-tips. The pins should be replaced within 12 hours. It is your responsibility to know where the extra-pins are, the persons who can help you replace the pins. You should restock the pins within a week.

Probe station policyChecklist before/during measurements

• Write down your name and information on the log-book.• Check if the pins touch the wafer/chuck surface.• Always use gloves when in doubt.• Use the vacuum suction on the manipulators.• Take permission before changing the existing wiring

configuration.• Switch off the lamp when done with probing/deprobing.• Don’t “force” the probe-tips on the wafer surface.• Don’t move the probe tips laterally after probing.• Don't change the chuck temperature after probing.

Probe station policyChecklist after measurements

• Leave the probe-tips at sufficient clearance.• All the probe tips are visible through the microscope.• Cool the chuck down to room-temperature.• Restore wirings back to their original configuration.• Switch off the lamp.• Note the finishing time in the log-book.

Special Notes 1. Small Wiring Change:

Front BackAll front and back connections are standard

MUST Restore

Special Notes2. Probe Pins (after use)

Top Side

Same heightEnough clearanceAll pins are in the field of view

If all probe tips are not visible

Move the microscope

Special Notes2. Pin breakage

Report

Fix immediately

Some users will be trained to change the pins. Keep a storage of extra pins in your group

Probe station policyViolation policy

First violation: Note to advisor, and suspend usage for a week.Second Violation: Note to advisor, and suspend usage for a month.Third violation: Barred from probe-station usage.

Damages must be self-reported. Unreported damages to the probe station will count as second violation.

Remember that you may be held responsible for broken probe-tips if you do not report existing damages before usage.

Finally, you should know where extra pins are, who can help you fix them. Replace the pins within next 12 hours. You should also restock the pins within a week and send a note to Sambit that it has been done.

KITE(Keithley Interactive Test Environment)

KITE(Keithley Interactive Test Environment)

KITE(Keithley Interactive Test Environment)

KITE(Keithley Interactive Test Environment)

KULT(Keithley User Library Tool)

Example code: Current Transients//Variable declarations. . . . .

//Initializedevint(); devclr(); clrcon();

//Switch matrix connectionsconpin(SMU1ConnectPinID, SMU1, 0); conpin(SMU2ConnectPinID, SMU2, 0);

//SMU settingslimiti(SMU1, 1e-3); limiti(SMU2, 1e-3); limitv(SMU1, 100); limitv(SMU2, 100);

//Apply biasforcev(SMU2, SMU2VBias);

//Measure currentdatacount=0; times[0]=0;meast(TIMER1, &ticks_start);do { measi(SMU1, &(SMU1current[datacount])); meast(TIMER1, &ticks_end); times[datacount] = (ticks_end-ticks_start);

datacount = datacount+1;} while (times[datacount-1]<TMax);

//Write output to file. . . . .

Example code: Set Temperature//Variable declarations. . . . .

//Initializedevint(); devclr(); clrcon();

//Initialize variablessprintf(cmd_setT,"RS%d",Temperature);cmd_setT_len=strlen(cmd_setT);sprintf(cmd_getT,"ST");cmd_getT_len=strlen(cmd_getT);

//Send temperature set commandsndcmd = kibsnd(TempContAddr,-1,GPIBTIMO,cmd_setT_len,cmd_setT);

//Is temperature set loopwhile(currtemp==(double)Temperature){ sndcmd = kibsnd(TempContAddr,-1,GPIBTIMO,cmd_getT_len,cmd_getT); rcvcmd = kibrcv(TempContAddr,-1,'\n',GPIBTIMO,Tdata_lenmax,

&Tdata_len,Tdata); currtemp = atof(Tdata+1); delay(10000);}