Arizona State University NanoFab
HIGH TEMPERATURE PROBE STATION
STANDARD OPERATION PROCEDURE
Rev A
ASU NanoFab
Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
Table of Contents
Contents
Table of Contents ........................................................................................................................................... 1
1. Purpose / Scope ...................................................................................................................................... 2
2. Reference Documents ............................................................................................................................ 2
3. Equipment / Supplies / Material ............................................................................................................ 2
4. Safety ..................................................................................................................................................... 2
5. Set Up Procedures .................................................................................................................................. 2
6. Operation Procedures ............................................................................................................................. 5
7. Process Data ......................................................................................................................................... 13
8. Revision History .................................................................................................................................. 14
Page 1
ASU NanoFab
Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
1. Purpose / Scope
This SOP provides the operating instructions for the “High Temperature Probe Station”. This
includes the mechanical probe station details, the micromanipulators, electrical connections,
measurements (IV’s with Agilent 4155B or CV’s with HP4284), software control of the switch
matrix (ICV Lite) and software to automate measurements(ICS).
2. Reference Documents
Agilent 4155C Users Guide V1.pdf
Agilent 5146C V2, Agilent 4155C Screen setup ref
Agilent 4284A CV Manual
Agilent Impedance Measurement Handbook
Dieter K. Schroeder, Semiconductor Material and Device Characterization
3. Equipment / Supplies / Material
Micromanipulator Probe Station with Video monitor
Micromanipulator, Model 525 Probe holder and tungsten probe tips
Thermal Chuck with Temperature controller
Agilent 4155C for IV measurements
HP 4284A for CV measurements
Agilent 41501B Pulse Generator
HP E5250A Switch Matrix
PC with software to control Measurements
PC for data storage
4. Safety
The main safety concern is when the probe chuck is hot (100-400C); do not touch samples or chuck
or any surrounding fixtures.
5. Set Up Procedures
The setup procedures are organized into the following topics: Mechanical, Micromanipulators,
Connections, Software Instrument Control
A. Mechanical Probe Station Controls
1. The probe station is inside a light-tight, shielded metal box with lid.
2. X & Y stage controls are on the left and right sides.
3. Z control of the probe ring in on the front side; note that it lifts the ring, not the stage.
4. Micromanipulators are positioned around the probe ring.
5. Microscope with video camera provide sample view on monitor; focusing knobs are behind
the microscope.
6. Microscope light & zoom controls are on the black box; front-right side of enclosure. Light
source is below the probe box with ON/OFF switch and fiber optics to microscope.
7. Traveling microscope X & Y controls are at the back, right side.
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ASU NanoFab
Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
8. Triax connections to the measuring equipment are on the back right side of the probe box and
labeled SMU1, SMU2, SMU3, SMU4 (front to back). Connection to the chuck is on the
bottom right side.
9. Note the “strain relief” connectors on both the left and right side of the probe station; the top
2 feed-through connectors are “triax” and the bottom 3 are “co-ax” connectors;
IMPORTANT: Do not mixup triax and co-ax connectors; All the probe stage wiring uses
triax connectors.
10. Triax to coax connectors are required for the direct connection to the cap bridge.
11. Vacuum control is the switch, front, left side; holds sample in place.
12. Emergency shut off is the red button on the front side.
B. Micromanipulators
1. The MM micromanipulators have a vacuum hold down; vacuum switch is on the side of the
base; push and hold to release and re-position; release to hold.
2. Micromanipulators have X, Y and Z controls on the backside; a coarse Z control is on the
front of the manipulators; note the triax wire is connected to the probe holder.
3. The triax connector from the manipulator goes to the triax feedthrough connector on the
back-left or back-right side of the stage; NOTE: the top 2 feedthrough connectors on both
sides are triax, the bottom 3 are co-ax connectors on both sides; All wiring in the station uses
triax wires and connectors; DO NOT MIX!
4. At the tip of the holder is the probe needle. Standard needles are ~20 mil diameter tungsten
wires with sharp needles on one end. The probe holder has an angled hole for the needle; a
set-screw in the end of the holder clamps the needle in place. Please do not bend the needles!
5. Needle heights are set for most wafer samples, but can be adjusted if needed. To change,
contact CSSER staff
6. If the needles are damaged, contact CSSER staff for replacement.
7. The needles often pick up material from probe pads and can generate contact problems for
subsequent probing. To clean the needles, use a swab with a little IPA and gently clean the
needle tips; inspect using the microscope.
8. In order to position the probe needles, follow this sequence;
a. Lower the needle to just above the sample using the coarse Z control.
b. Release the vacuum control and slide the manipulator until needle is visible in the
microscope.
c. Use the standard X, Y and Z controls to position the needle above the probe pad.
d. Slowly lower the needle until it makes contact (at contact, needle moves horizontally)
e. Follow the above steps to connect other manipulator needles to probe pads.
f. If the next pad is outside the microscope view, use the traveling microscope to locate
the next probe pad.
9. When you finish probing, lift the needle(s) from your sample using the Z and coarse-Z
controls; release the vacuum; rotate the manipulator to the back of the stage; Turn off the
vacuum; remove your sample.
10. Turn off the microscope light and the monitor; close the lid.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
C. Connections
1. The triax connectors from the manipulators goes to the “Strain Relief” triax feedthrough
connectors on the left or right side of the probe station. Triax wires (white) connect the
backside of these connectors to the corresponding feedthroughs on the wall of the probe box.
2. Ensure that each micromanipulator is connected to the corresponding “SMU” feedthrough;
NOTE: they are labeled (from front to back) SMU1, SMU2, SMU3, SMU4.
3. If you are using a connection to the back side of the wafer, ensure a connection between the
“chuck” connector on the back, bottom of the probe station and the appropriate SMU.
D. Software Instrument Control
1. ICV-Lite software controls the switch matrix. This allows you to choose between the Agilent
4155C and HP 4284A measurement systems.
2. Log into the computer using your ISSAC ID and password; contact nanofab staff for
computer access.
3. Open the ICV-Lite software; Use the pull-down menus;
Select “Development”
a. Select “Device Connections Editor”
b. Choose 4155C (for IV’s) or 4284A (for CV’s)
c. Select “Edit”; Switch matrix schematic appears; Inputs are the first column; outputs
are across the top row (connections to the probe box feedthroughs).
I
N
P
U
T
S
1
2
3
4
5
6
7
8
9
10
O U T P U T S
1 2 3 4 5 6 7 8 9 10
o
o
o
o
Default connections for the Agilent 4255C.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
O U T P U T S
1 2 3 4 5 6 7 8 9 10
I
N
P
U
T
S
1
2
3
4
5
6
7
8
9
10
Default connections for the 4284A
Note that Hi Pot & Hi I are connected to #9.
Low Pot & Low I to #10
o
o
d. Select “Make Connections Now”
e. Select “Finish”
4. This completed the section on selecting the measurement tool. You can close out the
software and continue with your measurements.
6. Operation Procedures
The operation procedures are divided into the following sections: IV Measurements, CV
Measurements, Temperature Control, Software Measurement Control.
A. IV Measurements
This probe station uses an Agilent 4155C for IV measurements; Current range is from sub-pA to
100 mA; there are both voltage and power limitations. The 4155C has 4 independent power
supplies [SMU1, SMU2, SMU3, SMU4] that will be connected to the corresponding 4
connectors on the probe box (back right side).
1. Place your sample on the probe stage; turn on the video monitor and light; Find correct probe
pads and position micromanipulator needles (see section B ); note corresponding SMU
2. Agilent 4255C Front Panel Operation (refer to photo). Note the following blocks:
a. Display on the left side with 7 vertical soft keys and 8 horizontal soft keys. Soft key functions
change with screen.
b. Page control block; just to the right side of the display. The 4 gray keys in a column allow
one to set up and measure devices; start with the top key [Chan], then [Meas] then [Display]
and then [Graph/List].
c. Knob to read out data points and arrow keys to move around screens.
d. Measurement Block (right top); 6 keys;
i. top row [Single, Repeat, Standby];
ii. bottom row [stop, Append, Stress(yellow)]
e. Integration time keys; [Short, Medium, Long]: “short” tends to be noisy, “medium” is
usually good, “long” yields the best resolution, but is slower]
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
f.
Entry Block; Edit keys on left, Key pad with numbers or alphabet, Far right [Enter key], [blue
key] for alphabet, [green key] for special characters. Note right column next to key board
with suffix keys (m=milli, u=micro, n=nano, p=pico, f=femto).
g. Ibasic programming keys (generally not used any more)
h. File keys for saved programs. (generally not used any more)
3. Short Version of front panel measurement setup
The following is a very brief description to set up and measure a 2-terminal device.
a. Find the page control block with 4 gray keys in a column.
b. Start with the top key [CHAN]; use soft keys (right side); Mode box [sweep];
choose “best” device representation for your sample [MOSFET], [Bipolar], [Diode].
c. Select [MEAS]; enter Start, Stop, Step voltages and Compliance current.
d. Select [Display] key; enter graph X-axis Min, Max & Y-axis Min, Max, Linear or log scales.
e. Select [Graph]; the blank graph is displayed.
f. Select [Medium] integration time in the measurement bock.
g. Select [Single] in the measurement block; measurement starts; green light is on; results
show in graph; save your data.
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ASU NanoFab
Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
Agilent 4155C photo of the front panel.
For this 2-terminal example, connect your device to micromanipulators wired to SMU1 and SMU3.
4. Detailed Front panel measurement setup: Details steps and corresponding screen views
a. Select [Chan] key in the Page control block; in the display move curser to Mode box;
Soft keys (right side) include SWEEP, SAMPLING, QSCV plus Defaults, Bipolar, FET Vd-Id,
(more ½), FET Vgs-Id, and Diode VF-IF, (more 2/2); Choose best fit for your device.
For example, Select [Sweep] and then [Diode] for any 2 terminal measurement.
Display:
Unit
SMU1
SMU2
SMU3
SMU4
Vname
VF
Iname
IF
Mode
V
Func
VAR1
V
I
Common
Const
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
b. Select [MEAS], the 2nd gray key, in the Page control Block; Use arrows to move around
screen; Use soft key selections and/or key-in values and hit [Enter] key (on right side of
entry block).
Display:
UNIT
NAME
Sweep Mode
Lin/Log
Start
Stop
Step
No of steps
Compliance
Power Comp
VAR1
VAR2
SMU1
VF
Single
Linear
0
10V
0.1
101
10mA
off
c. Arrow to a box labeled “Sweep*”, located in the lower right of the screen;
Soft key options for compliance:
1. Cont at any
2. Stop at any abnormality
3. Stop at compliance
Choose #3, stop at Compliance. (Turns power off if current exceeds value [10mA for this
example]).
d. Select [Display], the 3rd gray key, in the page control block.
This page sets the plot limits; Xmin, Xmax, Ymin, Ymax as well as liner or log scales
Display:
Name
Scale
Min
Max
X axis
VF
Linear
0
10
Y axis
IF
Linear
0
10m
Y2 axis
Arrow around the screen, pick the names and scale (linear or log) using the softkeys.
Key in values for Min and Max, use suffix keys if needed, & hit [enter] key.
For example, in the Max for Y axis, key in 10, hit the “m” key, and [enter] to get 10mA.
Note: Log works for all positive or all negative values, but not for mixed positive and negative values.
e. Select [Graph/LIST], the 4th gray key, in the page control block.
The graph will be displayed according to the above limits; you can always re-scale or “autoscale” later.
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ASU NanoFab
Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
f. Measure
Now, find the Measurement Block and its 6 keys (Top right):
Single
Repeat
Standby
Stop
Append
Stress
Below these keys are the integration time keys:
Short
Medium
Long
Centered at the top of the display graph is the integration time; default is “short”;
However, [Medium] is a generally a better starting choice.
Now, Select [Single] in the measurement block; Measurement starts; Voltage steps and current
is measured; Hit [Stop] if any problems!
Green light is on. Results are plotted as data is taken; Green light goes out when finished.
Note: select Soft key below the graph: [Marker]
Note: select soft key on Right side, [Marker on];
Turn dial to read measurement values; they are displayed above the graph.
Note: Repeat erases the 1st data set and re-measures the device, and continues until [stop].
Note: [Append] keeps the 1st data set and re-measures the device; both data sets show on graph.
g. Save the data!
You can save the data to either a 3.5” floppy drive or to a Windows XP computer.
Upon 4255C power up, the default drive is “Floppy”.
Ensure that the windows XP computer is turned on
1. To change the drive:
2. Select [System] Key; Select [Filer] softkey; Arrow to field at the top *DISK [PC] and select
“PC” from soft keys on the right (or else select the default FLOPPY).
3. After completing measurement, toggle the [Graph/List] key to LIST.
4. Select softkey [SPREAD SHEET]; Displays “ASCII SAVE” setup screen.
a. The box at the top “*DISK” [ ] should read *DISK [PC] or *[FLOPPY]
5. Arrow to Name box; Key in file name [FileName]; hit ENTER key (on far right side).
a. <= 8 characters for floppy disc files
b. <= 36 characters for network files
6. The rest of the fields should be automatically filled in with default values:
a. Output Data Boxes from [“1”] to [max]
b. Unit [OFF]
c. Delimiter [Space]
d. String Mark [NONE]
7. Select softkey [EXECUTE], bottom left.
8. After files are written, select softkey on the right [EXIT]
9. Select [Graph/List] to return to graph and/or more measurements.
Excel can “read” the text files to import data into a spreadsheet (use comma & space delimiters).
Find a computer with a 3.5” drive for the file transfer; save on a USB memory stick.
The “PC” for data storage has a 3.5” drive (see above)
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
10. Find your files on the PC:
Go to the Windows XP computer; turn on if needed; Allow ~5 min for computer to boot up.
Go to “My Computer”; Open Drive labeled “D:\Agilent 4155C” (shortcut on Desktop)
Saved files should be in this folder as “filename.TXT” files.
Move files onto your thumb drive and onto your own computer.
EXCEL will open the text files; use TAB and SPACE for delimiters.
Test conditions are at the top of the file followed by the data; Appended data follows the initial
values.
IMPORTANT: Delete your files from the common area “D:\Agilent 4155C” when finished.
5. Re-assigning SMU’s
One more useful and helpful option is the following:
This shortcut saves moving connectors or micromanipulators.
Assume a 2-terminal measurement with micromanipulators connected to SMU2 and SMU4.
Select [Chan] key; in the display move curser to Mode box; select [Sweep].
Soft key choices (right side) include MOSFET, Bipolar, Diode, …;
Select [diode] for any 2 terminal measurement.
Display is as below.
Display:
Unit
Vname
Iname
Mode
Func
SMU1
VF
IF
V
VAR1
SMU2
SMU3
V
I
Common
Const
SMU4
Use arrow keys to go to first Vname entry [VF].
Now, select soft key on the right column labeled [channel assign];
Curser moves to SMU1 box; soft keys are now labeled [SMU1], [SMU2], [SMU3] and [SMU4].
For this example, re-assign the VF row to SMU2 using the softkey;
Curser moves down one row; re-assign SMU2 to SMU1, since it is not used for this example.
Curser moves to SMU3 row; re-assign SMU3 to SMU4 using the softkey;
Again, since SMU4 is not in use, re-assign to SMU3.
Important! use softkey [exit channel assignment]; display now reads:
Display:
Unit
Vname
Iname
Mode
Func
SMU1
SMU2
VF
IF
V
VAR1
SMU3
SMU4
V
I
Common
Const
Now, continue through the next 3 page control keys and set up the measurement range & display.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
B. CV measurements
We will review the front panel of the 4284A Impedance Bridge and the many options and then
illustrate a simple CV measurement. This bridge measures impedance (Z) and phase angle (θ)
and then calculates the equivalent parameters such as parallel Cp with parallel G (conductance).
1. Use the ICV Lite software to connect the “High” and “Low” bridge terminals to 2 of the
SMU connectors (see section D. Software Instrument Control).
2. The 4284A has a display with 5 soft keys on the right. Choose fields using the Arrow keys;
key in values with the number pad and the “Enter” key. At the top center are 3 keys: Display
Format, Meas Setup, Catalog/system.
3. Select Measurement Setup key;
Arrow to Function; soft key choices are below;
See the Agilent Impedance Measurement Handbook for definitions of terms
Function
Cp-D
Cs-D
Lp-D
Ls-D
R-X
G-B
Cp-Q
Cs-Q
Lp-Q
Ls-Q
Z-O(deg)
Y-O(deg)
Cp-G
Cs-G
Lp-G
Ls-G
Z-O(rad)
Y-O(rad)
Cp-Rp
Lp-Rp
More 1/6
More 2/6 More 3/6 More 4/6 More 5/6 More 6/6
Similarly, arrow to FREQ and select frequency with soft keys; note the top and bottom keys
move in decade steps, the smaller arrows move in smaller frequency steps. For example, if
you start at 10KHz, the top key will shift to 100KHz and the bottom key to 1KHz; the
smaller arrows allow the following frequencies:[10k, 12K, 15K, 20K, 25K, 30K, 40K, 50K,
60K, 80K, 100K]; similar intermediate values are available starting at 1K, 10K, 100K.
Next arrow to LEVEL and set the ac voltage; typical values are 25 mV to 50 mV.
Arrow to Bias field and enter a DC voltage on the number pad, followed by the enter key;
turn on DC voltage with the key (bottom center); red light should turn on.
Arrow around the screen and fill in other fields as needed.
4. Connect your sample using the correct micromanipular(s) and/or substrate connection. Do
you get a good capacitance reading? Do you see the expected change in C with ±DC
voltages? See software section if you want to automate the CV measurements.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
Issue: Rev A
C. Temperature controls
The chuck temperature is controlled by the large unit to the left of the probe station. For high
temperatures (25C<T<300C) above room temperature, there is a heater in the chuck. For low
temperatures, a refrigerant is circulated through the chuck.
1.
2.
3.
4.
5.
6.
The control panel is on the left side of the temperature control unit.
The main power switch is at the bottom center of the panel; to operate, turn on.
The top temperature control box is for temperatures above RT.
Set the desired temperature using the dials and red readout screen.
The current temperature is the green reading.
Turn on the power switch for the heater. Wait! System checks conditions before turning on the
heater.
7. Chuck temperature will slowly increase to the setpoint.
8. Temperature will arrive at the setpoint and generally oscillates a couple of degrees around the
setpoint. Now, run your measurement and collect data. Set a new temperature and repeat. When
finished turn the heater off; chuck begins to cool. Cooling rates are slow so you can often collect
measurements within a very short time, relative to the cooling rates.
9. For temperatures below RT, there are two set points that need to be controlled.
10. First, set the refrigerant temperature using the setpoint arrow keys; turn on the refrigeration unit.
IMPORTANT; this temperature must be below the desired target temperature.
11. Second, set the target temperature on the second temperature control box; turn on “cool”.
12. If you plan to go very far below room temperature, you will need to place the extra shields above
your sample. This setup will prevent moisture from condensing on your sample. Put the shields
in place; note the side openings for the micromanipulators. Position the probe needles on your
sample.
13. Next, turn on the N2 gas on the back wall and adjust the flow meter. Purging the chamber of
water vapor is a slow process. When finished, turn off the N2 gas on the back wall.
14. Measure your sample; the chuck temperature changes are slow.
15. Remove shields etc when finished. Turn off the heater or cooling control unit; turn off the main
power switch.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
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D. Software control of measurements
ICS software allows the programming of measurement conditions and data collection and saving
both the program and data. A short overview of the software follows
1. Log in to the computer and open the software “ICS”
2. On the screen are “icons” and at the top are the typical windows pull down menus.
3. Use the icons and start on the left and continue to the right.
4. Instrument: select either the 4155 or the 4284 and select connect.
5. New: enter a name for your program; select OK; this will become the file name.
6. Device: select the schematic for your device from the menu; schematic shows up with small
adjacent boxes for each connection point.
7. Source units: Power supplies are listed, SMU1, SMU2, SMU3, SMU4; highlight the desired
power supply, click on the corresponding square on the schematic; continue with other
SMU’s.
8. Double click on SMU; resulting screen is similar to the front panel; you will need to fill in
all the measurement conditions and select the data (V, I) to be measured.
9. Options: select this key and set up the compliance and integration time.
10. MEAS key; opens the measurement controls: single, append, stop, auto seq. Selecting the
“single” key starts the measurement.
11. AUTO Sequence: you can generate several programs and chain them together in an auto
sequence.
12. Measure you sample: select “single”, results are placed in a “spreadsheet”; select the
“spreadsheet” key and select the data for each column.
13. Select Graph: This generates a graph of the data in the spreadsheet; auto scales the data. The
graph button allows changes to all graph paramters.
14. Save to EXCEL: open Excel in the background, select the columns of data (shift, select); Go
to Edit menu and select COPY (note that Ctrl C does not work!); open Excel, paste data into
Excel (note that Ctrl V does work!), save your data!
7. Process Data
Frequently, the measured data is exported to Excel. Calculations and graphs can be generated within
Excel. For example, if you measure both forward and reverse currents for a diode, you can plot the
log[ABS(I)] versus V. This allows you to plot a wide range of currents with both positive & negative
values.
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Title: HIGH TEMPERATURE PROBE STATION STANDARD OPERATION PROCEDURE
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8. Revision History
Effective
Date
7/13/2016
Originator
Wayne Paulson
DESCRIPTION OF REVISION
Initial Release
Issue
A
B
C
D
E
F
G
H
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