GCA 8500 Illumination Qualification Procedure - NanoFab · PDF fileThe Air Handler Unit (AHU) located behind the control console rack. ... Title: GCA 8500 ILLUMINATION QUALIFICATION

Arizona State University NanoFab

GCA 8500 ILLUMINATION QUALIFICATION PROCEDURE

Rev A

ASU NanoFab Title: GCA 8500 ILLUMINATION QUALIFICATION PROCEDURE Issue: Rev A

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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 ................................................................................................................................3 6. Operation Procedures ...........................................................................................................................5

7. Process Data .........................................................................................................................................5 8. Revision History ................................................................................................................................13


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1. Purpose / Scope 1.1. This document covers the procedure for adjusting and verifying the MAXIMUS illumination

source on the GCA 8500 stepper. This procedure should be performed at least once per week to

determine the proper exposure time based on light output for each job. It is suggested that you

review this document thoroughly before proceeding with the operation of this tool & always

check with staff if an unusual event occurs during the stepper operation.

2. Reference Documents 2.1. Chemical Safety & Hazardous Waste Management Rules & Procedures Handbook

2.2. GCA Reticle Handbook

2.3. GCA Master Operating Program Handbook Version 6.05.1

3. Equipment / Supplies / Material 3.1. GCA 8500 stepper reticle designed within the specifications defined in the GCA Reticle

Handbook. Users should make themselves completely familiar with the contents of this

handbook prior to scheduling training on the system.

3.2. Photoresist coated samples.

3.3. GCA 8500 consisting of the following sub-systems:

3.3.1. The environmental chamber which houses the illumination system, reticle and wafers

stages, and several other electronic and optical systems.

3.3.2. Control console containing the keyboard and computer display.

3.3.3. The Dark Field Alignment System (DFAS) which is located in the control console rack

above the control console computer.

3.3.4. The Air Handler Unit (AHU) located behind the control console rack.

3.3.5. Power supply for the laser interferometer system.

3.3.6. The interchangeable wafer chucks which handle pieces up to 4” wafers and associated

pedestal chucks.

3.3.7. The Atmospheric Compensation System (ACS) which controls the environmental

chamber ambient conditions.

3.3.8. The Reticle Management Systems (RMS) that houses and manipulates the 10 mask

holder magazine.

3.3.9. The Automatic Wafer Handler (AWH) which is designed to automatically load and

unload wafers to the stage but is inactive on this system.

4. Safety 4.1. Identified safety concerns:

4.1.1. Mercury arc lamp illumination source presents heat, ozone, explosion and toxic mercury

hazards.

4.1.2. Moving stage assembly presents pinch points.

4.1.3. There are several laser systems, most notably the interferometer system that meters the

wafer stage and optical column.


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5. Set Up Procedures 5.1. Before running the software to perform the illumination check, a wafer should be loaded onto

the stage. Preferably a 4” Si wafer.

5.1.1. Go to the computer console:

5.1.2. Log into the appropriate directory; ex. “L I [10,X]” (X is the directory number for your

group)


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5.1.3. Enter the appropriate password.

5.1.4. Type “LOAD” to move the stage to the load position for loading a substrate.


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5.1.5. Load the substrate sample on the chuck and load chuck onto the stage. Be

EXTREMELY CAREFUL not to hit the objectives when loading the chuck.

6. Operation Procedures 6.1.1. Next, go to the computer and type in the command “UNIF”.

6.1.2. The menu for Illumination Qualification will appear on the screen with four menu

choices.


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6.1.3. First, select menu item 3 to check and mechanically peak the UV intensity on the

MAXIMUS illumination assembly.

6.1.3.1. The system will proceed to clear the platen if a reticle is present. Then it will ask

you to type “C” to continue. Do so.

6.1.3.2. Next it will ask to switch the Auto/Manual switch on the wafer handler. There is

no switch so type “C” to continue.

6.1.3.3. The system will proceed to request stage initiation by pressing “RESET” and

“MAN”, “S/C”, “MAN” to start the stage and move to the UV detector.


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NOTE: When pressing the “RESET” button, wait until the red LEDs on the wafer

handler flash on and off before continuing with the “MAN’, “S/C, “MAN” buttons.

Also, press the buttons for at least one second or they may not properly register the

selection.

LEDs on the wafer handler that flash

when the “RESET” button is pushed.


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6.1.3.4. The console screen will state the switch for the manual shutter control needs to be

flipped to the “ON” position. The switch is located in the rack below the console

keyboard. Then type “C’ on the keyboard to continue.

Manual shutter switch


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6.1.3.5. At this point, the system, will display the current bulb intensity on the monitor

above the operator console showing the value of intensity in mW/cm2.

6.1.3.6. Go to the MAXIMUS housing in the environmental chamber to the right of the

stepper and locate the three X, Y and Z adjustment knobs. Adjust the knobs to peak


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out the value indicated on the monitor displaying the intensity.

6.1.3.7. Once you have peaked the intensity, type “C” on the console keyboard and flip

the manual shutter switch to the “OFF” position. Then hit “Return” to take you to the

main menu.

6.1.4. To map the illumination uniformity select “1” from the main menu.

Z, Y and X bulb adjustments


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6.1.4.1. The system will guide you through some on-screen commands. Respond same as

steps 5.1.8.1 thru 5.1.8.4.

6.1.4.2. At this point, the system, will display the map of intensity measurements on the

monitor above the operator console showing the value of intensity in mW/cm2. The

map will contain 21 x 21 measurement points across the lens surface.


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6.1.4.3. Once the 21 x 21 measurements is completed, the screen will display the

statistics. Record the mean illumination value and % uniformity in the log book.

6.1.4.4. Once you have peaked the intensity, type “C” on the console keyboard and flip

the manual shutter switch to the “OFF” position. Then hit “Return” to take you to the

main menu.

6.1.4.5. Type “4” to exit the main menu.

6.1.4.6. If there are no further tests, you can log off the system by typing “L” space “O”

and “Return”.

7. Process Data Text

Record the Mean intensity and the %

uniformity.


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8. Revision History Effective

Date Originator DESCRIPTION OF REVISION Issue

7/6/15 Kevin N. Initial Release A

B

C

D

E

F

G

H