Setup : vega

What can it do?
  1. Room temperature max 3 terminals IV.
  2. Room temperature 2 terminals CV
  3. Four terminal measurements can be done by shorting two terminals using switch matrix
What it cannot do?
  1. Temperature dependent measurements
  2. Stress Measurements/ Pulse Measurements
What instruments are present?
  1. Keithley 236 SMU  - 2 Nos
  2. Agilent LCR Meter  - 1 No.
  3. Keithley 708 A Switch Matrix  - 1 No.
What are the current, voltage and frequency specifications?
  1. Through SMU : Max Voltage = 110 Volts
    236 Output Specification
    Max Current = 100 mA
  2. Through LCR Meter : Max Frequency =20 Hz
    Min Frequency =1 MHz
How are instruments connected?
  1. Two SMUs connected to switch matrix columns 1 (SMU1) & 2 (SMU2)
  2. GNDU connected to switch matrix column 4
  3. Manipulator A,B,C & D connected to rows A,B,C & D respectively
  4. Chuck connected to Row G
  5. LCR High connected to column 10
  6. LCR Low connected to column 11
Setup Usage Instructions:
  1. Login using your charlab domain username and password.
  2. If you are first time user, copy the codes from E:\Users\codes folder to your network drive. (All the codes are appropriately named)
  3. Probe your device properly and make a mental note of which manipulators you have used to make contacts.
Code Specific Instructions:

For CV:

  1. Run the CV_2terminal.exe.
  2. The code will ask you for the following values
    1. Frequency (Enter in Hz)
    2. Start and End values of DC bias sweep (Enter in Volts).
    3. AC value of voltage (Enter in Volts).
    4. File name where your data will be stored (for eg: CV_output.dat)
    5. Integration time (0 for FAST 1 for NORMAL 2 for SHORT).
    6. Step size
    7. For Probe connections:(use a,b,c,d,chk for entering the values)
      1. For example if you are using chuck and probe c for the two terminal CV measurement then
      2. For high terminal enter : chk
      3. For low terminal enter : c
      4. NOTE: DO NOT use chuck as low terminal. you will not get proper CV
    8. Let the code run. You will get measured values of Capacitance is in picofarads.
  3. The data sheet will be generated in the same folder and it can be opened with the data plotting software ORIGIN.

For IV

  1. Run the appropriate code. (IV_2terminal.exe for two terminal IV, IV_3terminal.exe for three terminal measurements)
  2. The code will ask you for following values
    1. Start and End values of DC bias sweep. (SMU1 is used to sweep. Its hard coded in the code)
    2. File name where your data will be stored
    3. Integration time (0 for FAST 1 for NORMAL 2 for SHORT)
    4. Step size
    5. DC bias For SMU2 (If you do not want to force value from other SMU, put it as 0)
    6. For Probe connections:(use a,b,c,d,chk for entering the values)
      1. For example if you are using probe A and probe C for the two terminal IV measurement and you want to sweep the voltage on probe A and keep a fixed Bias on probe C then,
      2. for terminal 1 Enter : a
      3. for terminal 2 Enter : c
    7. The data sheet will be generated in the same folder and it can be opened with the data plotting software ORIGIN.
      Note: USE NEGATIVE value of step size if stop voltage is negative.
      (eg:Start voltage 0 Stop voltage -10 then Step Size =-1 ie a negative value of step size)
      NOTE: Users can refer instrument manual kept in cupboard for further assistance.