OPERATING PROCEDURES
EVG 501 WAFER BONDING SYSTEM
INCLUDING
EVG 301 CLEANING STATION
AN D
EVG 620 WAFER ALIGNING STATION
Rev. 2/9/2016
Material Restrictions:
All materials allowed for use in this equipment are
listed in PDF form on the WCAM My Web Space. To
view the listing following these steps:
A. Open the UW website
https://mywebspace.wisc.edu for My
WebSpace.
B. Log on using your UW NetID and password.
C. Click on the star in the upper left corner.
D. Under Bookmarks click on Group Directories.
E. Scroll down the list of organizations to
WCAM.
F. Click on WCAM.
G. Double click on the first file folder to open
“Approved Materials.”
H. Double click on the WebsiteRpt to view the
approved materials for equipment.
I. Within the PDF you can perform a search.
Overview
The EV system is comprised of two units: the EVG301 wafer cleaning station, and the
EVG501 wafer bonding station. The unit tooling is designed for 15 mm pieces, 50 mm (2 inch)
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wafers, 75 mm (3 inch) wafers or 100 mm (4 inch) wafers. The substrate can be silicon, glass, or
sapphire.
A complementary tool is the EV 620 aligner. The EV 620 system is designed for waferto-wafer alignment of 100 mm (4 inch) wafers. This is a desktop system with a manual stage for
backside alignment method. This method has a resolution of ± 2 µm. The aligned wafers are
clamped in a special chuck, which is then transferred to the EV 501 system for the bond
processing.
Three types of bonding can occur with the EVG501 station:
 Direct bonding – Wafers with smooth, clean (preferably prime grade) surfaces are in
direct contact without significant pressure. Bonding temperatures can range from
less than 100 °C to 550 °C (maximum temp of heating unit on EVG501).

Anodic bonding – Substrates are in contact and the bond is made by applying a large
electric field with temperatures ranging 300 °C to 450 °C to increase mobility of
mobile charges (e.g. Na+ ions). Typically, this type of bonding is used for permanent
joining of a Na+ containing borosilicate glass substrate and some semiconductor
wafer. Be sure to check your glass CTE to see how closely it matches your wafer CTE.
Pyrex 7740 is a standard glass used for anodic bonding. PLEASE CONTACT THE STAFF
MEMBER IN CHARGE IF YOU ARE DOING ANODIC BONDING. THERE ARE
ADDITIONAL TOOLS AND STEPS THAT ARE USED WHICH MAY NOT BE
DOCUMENTED IN THIS PROCEDURE.

Intermediate-Layer bonding – This method requires a layer between the substrates
for bonding. A metal layer can be used for eutectic bonding; or other layer types
such as polymers, solders, low temperature glass or soft, thin metal films for
thermo-compression bonding.
Preparation for Bonding
To prepare wafers for bonding the following basic steps are necessary:
1. Thickness measurement of the wafers, flags and field electrode (graphite or glass plate
used only for eutectic (graphite) or anodic (glass) bonding). This thickness
measurement is referred as the “stack height” and is needed to correctly adjust the
pressure applied to the wafer bow piston at the center.
2. Cleaning of the wafers. This can be wet-chemical or by plasma or both.
3. Optional rotational alignment the wafers in the EVG620 system. This may not be
necessary for most general users.
4. Check, with a bright light coming in at a small angle with respect to the wafer surface, or
with a microscope, if there are any particles before bonding. If so, re-clean or replace
the wafer.
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5. The actual bonding process, which can be run manually, or automatically for more
uniform control among a batch of wafers.
Stack Height Preparation (Contact staff person to
approve process parameters and correct tooling
components before processing if you are unsure.)

Stack thickness should be measured before bonding.
Stack = field electrode + both wafers + flags (if
used)
(Field electrode is only used for anodic or eutectic
bonding, and is the glass or graphite plate. Use
less than 500 N (112 lbs) of force when using the glass plate or it will crack!)

Wafers should be chemical and/or plasma cleaned before bonding.
Start-Up
1. Log into CRESS
2. At the equipment computer, open two programs: EVG 501 for the bonding station, and
EVG 301 for the cleaning station
NEXT – GO TO WAFER CLEANING PROCEDURES
OPERATING PROCEDURES
EVG 301 WAFER CLEANING STATION
Note: Deionized water is Fluid 0. No other
chemical fluids are available with our system.
Start-Up
1. Contact staff person to approve process
parameters, wafer size file and correct tooling components if you are unsure of the
procedure.
2. Main power to the system and computer should be ON.
3. Open and/or maximize the following program window: EV 301 – the cleaning station
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Operation
1. Operation is based on wafer size settings. To set the wafer size, download a settings file.
INITIALIZING and PROGRAMMING the cleaning head parameters
Objective: To download the correct INI file for the size wafers being bonded. There are INI files for 2-inch,
3-inch and 4-inch wafer size.
Note: The download is performed in REMOTE control. The cleaning station is manually operated in LOCAL
control.
1. Open “MY COMPUTER”/ C:\  EV301 folder INI folder.
2. Open the desired size wafer file folder.
3. Copy the appropriate INI file and paste it into the parent directory, OVERWRITING the file that is
already there.
4. Close all recently opened folders.
5. Maximize the EV301 Engineer program.
6. Click on REMOTE ON/OFF. Note the REMOTE button on the bottom of screen changes to GREEN
and ON.
7. Click on FUNCTIONS and then on the Maintenance button.
8. Click on “Download INI-file parameters.”
9. When download completed close Maintenance window. Click on EXIT FUNCTIONS.
10. Click REMOTE ON/OFF. Note the REMOTE button on the bottom of screen changes to RED and
OFF.
11. Minimize the EV301 Engineer program.
12. Continue with EV 301 operating procedures.
2. Once the correct settings are downloaded, ensure that the REMOTE is
OFF. This allows for the PRESETS to be used manually at the panel by
pressing the buttons.
3. Measure thickness of the field electrode and wafers to be bonded.
Use the Mitutoyo Digimatic Indicator located on the table near EVG
system.
Field electrode
Wafer 1
Flags
Wafer 2
______ mm
+ ______ mm
+ 0.05 mm
+ ______ mm
TOTAL STACK
= ______ mm
4. You may want to replace the alignment arm for the appropriate sized
wafer. The plastic arms can be found the ACCESSORIES or SPARE PARTS tub. Visual
alignment can also be done.
5. At the clean station control panel, press ALIGN (top
button) to move the arm in the
down position.
6. Place first wafer on stage against the align arm.
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7. At the cleaning station control panel, turn knob to desired preset 0 – 9. (only program 0 is
currently active with parameters – contact the staff if you need to add other programs).
8. To begin the clean cycle, press:

START – GREEN button on panel
START

ENTER – bottom
button on panel
ENTER
9. The program will automatically stop and alarm at completion and
the wafer can be removed from chuck. Press ENTER stop alarm.
ENTER
Process Option A: Aligner Station
before Bonding Station
Process Option B: Bonding Station
without aligning wafers
Place first wafer into aligning tool.
Repeat Steps 4-10 for second wafer.
Place first wafer into bonding tool.
Repeat Steps 4-10 for second wafer.
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OPERATING PROCEDURES
EVG 620 WAFER ALIGNING STATION
You may skip this section if you are not doing any
rotational alignment of your wafers or substrates.
Components:
This system is only for 100 mm (4-inch) wafers.
The bonding method is anodic bonding.
Components needed for manual aligning:
Bond chuck top
Bond chuck bottom
Bond chuck ruler
Carbon electrode
Glass for anodic bonding
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General Data on Substrate Alignment
Range of X & Y alignment
+/- 5mm
Rotation
+/- 3.5°
Resolution
0.06µm
Bond aligner accuracy
0.5µm for glass/silicon, 1µm silicon/silicon
Separation
Maximum 300µm adjustable in 1µm steps
Resolution of Z-movement
0.033µm
Alignment Mark Diagram
Area where alignment marks
may be seen
17.00 mm
12.00 mm
12.00 mm
Flat of substrate
Microscope Movement
Switch between stage and optic selection with the button on the
joystick
Y direction move joystick front or back
X direction move joystick left or right
Theta/Z directions turn the joystick clockwise or counter-clockwise to
move the optic in the Z-direction (focusing) or the stage in theta
direction (PHI axis).
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Manual Anodic Bonding Process
The following presents a basic overview of anodic bonding two silicon substrates. The detailed
process steps follow this section.
1. Load first substrate with bonding surface and alignment marks facing down.
2. Wait while the aligner performs wedge compensation (WEC) is between first substrate and
tool.
3. Use joystick to adjust objectives to substrate alignment marks.
4. Use joystick to adjust crosshairs to alignment marks.
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5. Load second substrate with bonding surface facing up and alignment marks facing down.
6. Use stage micrometers to align second substrate alignment marks to crosshairs.
7. Insert separation flags.
8. Wait while the aligner performs wedge compensation (WEC) is between first substrate and
second substrate.
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9. Use stage micrometers to do final alignment of second substrate to crosshairs.
10. Clamp the bond tool.
11. Remove bond top and proceed to EVG 501 for bonding process.
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Start-Up
1. Log into CRESS.
2. Ensure that all controls to the EV 620
are powered ON
3. If not ON complete the powering up in
the following sequence.
a. The main power switch.
b. The power control switch.
c. The green on button.
B
C
A
4. The EV Explorer window (not MS Windows) is automatically displayed.
5. Use the tracker ball to move the cursor. Use left button to double click on the
application icon EVGXX Machine Software.
6. A blank log in window will be displayed. Click on Login.
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7. A dialog window will appear requiring a user
name and password.
User name: User
Password: EV
User
EV
8. Click Login
9. Wait while the tool automatically goes
through initialization steps. You will be
prompted to move the tray out. The message
at the bottom will state:
!
Tray – Move Tray Out
10. Gently rotate tray out.
11. After the tray is completely out, the initialization will continue.
12. Wait for initialization to complete. The message on bottom of screen will state:

Initialization Okay
13. A blank align process application window will be displayed.
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Recipes
The alignment process is operated by recipes. Following are procedures for recipe operations:
 Creating a new recipe
 Saving a recipe
 Opening a recipe
 Starting a recipe
Creating a new recipe
1. In the menu, click on File / New or click on the new document icon
.
2. A recipe process window will open.
3. The following settings are standard for all recipes used in this EVG620 model.
Process:
Man. Anodic Bond
Process mode:
Crosshair
Tool Name:
4 inch Bondtool, Size 4 inch
Tool Name:
4 inch Chuck, Size 4 inch
Separation:
30um
Chuck:
1 Zone - Manual
Process contact force: 1100 mbar
WEC contact force:
500
4. Measure thickness of substrates and key value into
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Saving a recipe
1.
2.
3.
4.
In the menu, click on File / Save or click on the new document icon
Or, File / Save As.
Name the recipe
Click OK. The file will be saved in the default directory.
.
Opening a recipe
1.
2.
3.
4.
In the menu, click on File / Open or click on the new document icon
The default directory will open.
Double click on the selected recipe; or click on the recipe and then OK.
The recipe process window will open with the selected recipe.
.
Starting a recipe
1. Click the green RUN arrow .
2. This is a manual alignment station. As the
process recipe runs, the screen will prompt
the user through the alignment steps.
Typical Recipe Process Run
NOTE: If the cursor is sitting on the bottom bar of a process
screen, the EV Explorer Window will appear. Click on the
EVG icon at the botton of the Explorer Window to return to
the process recipe.
1. Open a recipe.
2. Check the recipe settings, including the substrate thickness.
3. Click on the green arrow
Run to start
the recipe.
4.
WAIT several minutes for the process to begin
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5. Screen will display each process step with illustrations and directions. Complete each
process step directions and click
Continue at the bottom of the screen.
Begin process
Click Continue
Configure Optics
(Skip – this option
is not available)
Click Continue
Retrieve bond tool
from storage rack
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Insert Bond Tool
Check placement
of vacuum holes
See following
method for tool
insertion
Insert Bond Tool
Check placement
of bond tool.
Align vacuum
holes on bond tool
to vacuum holes
on stage.
Insert Bond Tool
2
Insert front edge
of bond tool first.
This is a snug fit.
Press front edge
of bond tool
against spring pin.
Then insert back
edge of bond tool.
1
Click Continue
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Remove clamps
Press down and
turn each clamp
until top line is
vertical
Click Continue
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Remove flags
Flags are not used
in this process
method
Press each flag
outward.
Click Continue
Insert chuck.
This part has
already been
inserted vacuum
connected.
Click Continue
Insert ruler with
pins down and flat
at 3:00 position
3 o’clock
Ruler handle at
5:00 position
Click Continue
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Insert bond glass
HANDLE GENTLY!
The glass slides
under ruler
TOP pointing to
the left
TOP
TOP
Click Continue
Insert wafer
Position with flat
to the right at 3:00
position
3 o’clock
Bond surface
DOWN
ALIGNED TO the
ruler
ON TOP of glass
NOTE: Placement
of the top
substrate is
critical. No
rotation of the top
substrate is
available.
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Click Continue
Remove ruler
Carefully lift ruler
away from glass
and wafer.
No vacuum is on
Click Continue
Move tray in
Vacuum is on to
hold glass and
wafer
Center stage
Adjust 3
micrometers to
center position 5.0
Click Continue
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Check the positions of all three micrometers. The scribed line at 5.0 indicates the center
position.
Scribed line
WEC
Wait while the
aligner makes
adjustments to the
first wafer
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Adjust microscope
Click on Position.
Use cursor and button to select
LEFT or RIGHT microscope
objective button on bottom of
screen
Move objective with joystick to
image alignment marks on wafer
Zoom focus by rotating joystick
knob.
Adjust image by sliding controls.
TIP: Microscope positions can
be saved and stored for each
recipe.
Click Continue
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Adjust crosshairs
Click on
CONTROLS to
open crosshair
control box
TIP: Increase
thickness to
identify crosshair
location
Click on LEFT
CROSS or RIGHT
CROSS button on
bottom of screen
Move crosshair to
image alignment
marks on wafer by
clicking directional
arrows
Slide controls to
adjust crosshair
image
Click Continue
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Move tray out
The first wafer will
be held in the tool
by vacuum
The tray will come
out with only the
glass to load the
second wafer
Click Continue
Insert ruler
TOP
Reposition the
glass and ruler
Click Continue
Insert wafer
Position with flat
to the right at 3:00
position
3 o’clock
Bond surface UP
ALIGNED TO the
ruler
ON TOP of glass
Click Continue
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Remove ruler
Carefully lift ruler
away from glass
and wafer.
No vacuum is on
Click Continue
Move tray in
Vacuum is on to
hold glass and
wafer
Click Continue
Pre-align
Use 3 micrometers
to align second
wafer to crosshairs
Click Continue
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WEC
Wait while the
aligner makes
adjustments to the
second wafer
Final alignment
Use 3 micrometers
to align second
wafer to crosshairs
Click Continue
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Before the clamps,
make final align of
second wafer.
Use 3 micrometers
to align second
wafer to crosshairs
Insert clamps
Press down and
turn each clamp
until top line is
horizontal
Click Continue
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Remove bond tool
Wait while
instrument
releases bond tool
Carefully lift bond
tool out of the
aligner
Pull bond tool
towards the front
and lift out back to
free bond tool
The stack is
clamped and
ready for bonder
Click Continue
End of Process
Exit out of aligner
and continue to
bonder
DO NOT CLICK
CONTINUE
Click Exit
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Exit returns to
initial menu
screen
Click on the Park
Tray icon.
Click Continue
You will be
instructed to
move the tray in
Click File / Exit
NEXT – GO TO WAFER BONDING
PROCEDURES
Check bonder for anodic setup before
continuing
Use only the carbon electrode with
the aligner chuck.
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OPERATING PROCEDURES
EVG 501 WAFER BONDING STATION
Pre-check
1. Measure thickness of the field electrode and wafers to be bonded before cleaning.
Use the Mitutoyo Digimatic Indicator located on the table near EV system.
Field electrode
Wafer 1
Flags
Wafer 2
______ mm (only used for anodic bonding [Glass or graphite])
+ ______ mm
+ 0.05 mm
+ ______ mm
TOTAL STACK
= ______ mm
2. Adjust the micrometer on the top to the
TOTAL STACK measurement.
3. Clean the wafers. See CLEANING procedures.
Start-Up
1. Main power of system and computer = ON.
2. Open and/or maximize the EV501 wafer bonder program window.
3. Maximize the Manual Setup Menu.
4. On the Activation Bar, ensure PUMP is OFF. If not, press PUMP and wait.
5. Check the top of the yellow Balzers valve. The center pin should be DOWN with the pump
off. This indicates that the gate valve is closed for the turbo pump.
6. On the Activation Bar, press VENT to bring the bonding chamber to
atmosphere.
7. When venting has completed, on
the Activation Bar, press VENT.
8. Open the bonding tool by pressing
and holding both GREEN buttons
on bonding panel until bond
chamber has fully opened.
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9. Each bond chuck assembly is stored on the shelving
unit near the bonder.
10. Check set-up for correct bonding tools. Contact staff
person for correct setup if you are unsure or have
any questions.
See following diagrams for tooling setup.
Top Electrode or Pressure Plate
Top electrode setup has two
components:
1. Top pressure plate
For Anodic Bonding: you can
use the quartz insert plate and
contact finger:
For Thermo-Compression Bonding:
you should use the metal insert:
Quartz insert with opening for
piston and lip for metal finger.
Stainless steel insert with opening for
piston (in center)
(Can be used for force > 2000
Newtons)
Top
Electrode or
Pressure
Plate
2. Anode electrical contact
finger
Contact metal (finger) installed
on top of quartz insert (circled
in red)
Cross sectional assembly of field electrode, waferstack and bonding chuck
Field electrode &
Alignment ruler (if
used)
Second wafer
Flags
First wafer
Bond Chuck
2-inch
3-inch
4-inch
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Bonding Chucks
Component
2-inch
3-inch
4-inch
Bond chucks
After placement - check
the flag operation.
Bottom
Bonding
Assembly
Field electrodesFor use with:
bow pin & 2-inch rulers
bow pin & 3-inch rulers
bow pin & pressure
Electrode for force
>2000N
Electrode for force
>2000N & rulers
For uniform pressure
across wafer
Rulers:
Electrode for
force >2000 N
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Example of Tooling Setup
1. Select correct tooling components. Install chuck to equipment. Check operation of flags.
2. Position first wafer onto the bond chuck. (thinnest wafer recommended to be on the
bottom)
a. Make sure the bond side of wafer facing up (especially for double polished wafers).
b. Align against the three (quartz) alignment pins – 2 pins at the wafer flat and 1 pin at
wafer side. The quartz alignment pins should not be taller than the bottom wafer.
3. Ensure the separation flags are positioned over the first wafer.
4. Position desired ruler on the chuck by aligning the ruler holes onto the chuck metal pins.
The alignment rule is for positioning the second wafer. Adjust set screws to level the ruler.
5. Position the second wafer onto the bond chuck using the appropriate vacuum wand.
a. Bond side of wafer down.
b. On top of the separation flags.
c. Align to the ruler, if alignment ruler is used.
6. Place field electrode on top of wafer stack. Ensure that the field electrode sits flat and is
not resting on top of the ruler or separation flags.
7. Go to bonding modes and procedures.
Bonding Modes
 Manual Setup Menu has individual sections for the bonding processes that must be
set. Buttons on the Activation Bar activates the functions.
Heating time and temperature –
Electrode force –
Voltage –
Bonding time –
Cooling time and temperature–

h:mm:ss
h:mm:ss
h:mm:ss
0-550C
1-7000 N
0-1200 V
TIP: Heating time
set at 0:00:00
heats unit as fast
as possible.
0-550C
Automatic Setup Menu enables you to select a written program or create a new
program of bonding processes. RUN on the main menu bar activates a loaded
program.
TIP: Close chamber before proceeding to second
wafer to prevent DI water splashing into chamber.
Bonding Procedures
1. Position first clean wafer with bonding side facing up on the stage. Use the alignment pegs
to center the wafer.
2. On the Activation Bar press FLAGS IN.
3. Close the chamber by pressing and holding both GREEN buttons on bonding panel until
chamber has fully closed.
4. Clean second wafer, then open chamber again using the GREEN buttons and place the
second wafer facing down using the alignment pegs to position. The flags will keep the
wafers separated until the bonding process has been activated.
5. Close the chamber by pressing the GREEN buttons.
6. Log off of CRESS.
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Example Of Process Steps For Operation Modes
(look at either the Manual column OR the Automatic column for step by step operation. There is no relation
between the adjacent blocks in the manual and automatic steps.)
Step
1
2
3
4
5
6
7
8
9
10
Manual SETUP Mode
Minimize the Automatic Setup Mode
submenu
Maximize the Manual Setup Mode
submenu.
Click the PUMP
button on
Activation Bar. The
pump should be on
and the Balzers
valve pin up.
Set parameters on menu:
Heating
top & bottom
time & temperature
0-550C
Electrode 1-7000N
Voltage
0-1200V
Bonding
time
Cooling
top & bottom
time & temperature
Click H button on Activation Bar to start
heating process.
If the field electrode has the spring center
for the bow pin movement then click
WAFER BOW button to move down the pin.
Click F button to pull out flags.
Click E button on Activation Bar and a
submenu will show. (E corresponds to
Electrode FORCE)
Verify the correct tooling configuration
At end of bonding time, click E to release
force. (E = Electrode FORCE)
Click C button on Activation Bar to start
cooling process.
Click PUMP button on Activation Bar to turn
off the pump The pump should be off and
the Balzers valve pin down.
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Automatic SETUP Mode
Minimize Manual Setup Mode submenu
Maximize the Automatic Setup Mode
submenu.
The process recipe file can be edited or
a new process created and named.
Click on FILE, select desired process file
and click OK.
Click RUN and allow the program to
complete process  View process steps on the
PROCESS MONITOR submenu
 View the processing graph on the
RECORDER submenu
At the end of the process recipe,
minimize AUTOMATIC SETUP submenu.
Maximize MANUAL submenu
Click PUMP button on Activation Bar to
turn off the pump. The pump should be
off and the Balzers valve pin down. Do
not vent until pin position is verified.
Click V button on Activation Bar to vent
the bonding chamber.
Hold down both GREEN buttons on
bonding panel to open chamber.
Hold down both GREEN buttons on
bonding panel to closed chamber.
Do not vent until pin position is verified.
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12
13
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15
Click P button on Activation Bar to start
nitrogen purge process.
Click V button on Activation Bar to vent the
bonding chamber
Hold down both GREEN buttons on bonding
panel to open chamber
Remove bonded wafers
Hold down both GREEN buttons on bonding
panel to close chamber
Record use in logbook
Remove bonded wafers
Record use in logbook
For help on automatic scripts and commend definitions, please contact the staff for more details.
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