lambda physik compex 301 excimer laser operating manual … lambda physik... · document: lambda...

Lambda Physik COMPex 301 EXCIMER LASER OPERATING MANUAL

Version: 2.0 April 2012

UNIVERSITY OF TEXAS AT ARLINGTON

Nanofabrication Research and Teaching

Facility

DOCUMENT: Lambda Physik COMPex 301 Excimer LASER OPERATING PROCEDURES Version 2.0

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TABLE OF CONTENTS

1. Introduction…………………………………………….…………...3

1.1 Scope of Work…………………………………….…......3

1.2 Description…………………………………….…….……3

1.3 Safety……………………………………………....……..3

2. Hardware..............................……………………………….….....5

3. Requirements……………………………………..….….…….…..7

3.1 Training…………………………………….……..…...….7

3.2 System Restrictions………………………...……..…....7

4 Operating Procedures.………………………..…..…………......9

4.1 System Pre-Checks………………………….…...........9

4.2 Lambda-Physik COMpex 301 LASER operation…..10

5 Recipes…….………………………..…..……………….…..……14

5.1 Recipe Guidelines....................................................14

6 Gas Flush and Fill Procedures ………………………………..16


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1.0 INTRODUCTION

1.1 Scope

These procedures apply to the Lambda Physik COMPex 301 Excimer LASER system. All maintenance should follow the procedures set forth in the manufacturer’s maintenance and operations manuals. This document is for reference only.

Users must first coordinate with University of Texas at Arlington’s EH&S Laser Safety Officer (LSO) to ensure compliance with established federal and state procedures before operating this equipment (http://www.uta.edu/campus-ops/ehs/radiation/laser.php ).

User’s must also receive training and be authorized by trained Nanofab staff before operating

this equipment

1.2 Description

The Lambda Physik COMPex 301 Excimer LASER system is capable of producing a stable high energy pulsed rare gas-halide laser . The COMPex 301 excimer laser provides up to 10 watts of 10-50ns pulsed Krypton Fluoride ( KrF ) laser emission at wavelength of 248nm. The short pulse durations and the use of unstable resonator results emission bandwidths of a few Å and beam divergence of 2-4 mrad. This high energy pulsed beam is used with Neocera PLD vacuum chamber and focusing system to strike target materials that are to be deposited on sample pieces or up to 4” diameter wafers. The process can occur in ultra high vacuum with optional background O2 or N2 gas pressure and substrate heating up to 650C°.

The pulsed laser deposition technique (PLD) can be used to fabricate high quality crystalline films, nitride, oxides, YBCO, ZnO and other approved thin films.

1.3 Safety

1.3.1 This tool emits a narrow beam of intense Ultraviolet Light. The radiation of the excimer laser lies outside the visible spectrum so the light will be unable to be detected by the human eye. Make sure that suitable protective eye ware - 248 nm UV goggles and UV face shields are available for putting the laser into operation. Ensure laser safety eye ware is worn by everyone operating on or near the laser and any unauthorized person without laser safety eye ware must LEAVE BAY3.

1.3.2 Ensure all laser operators remove reflective watches or jewelry from their bodies. Make sure your gloves cover all exposed skin.

http://www.uta.edu/campus-ops/ehs/radiation/laser.php


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1.3.3 Keep all flammable materials such as clean room paper, notebooks, solvent bottles ( Methanol, Acetone, Isopropanol Alcohol ) away from the beam path.

1.3.4 Do not remove safety eye ware during laser beam alignment (use a piece of fused

silica or Laser Zap paper to determine the position of the beam). Align the optical components starting with the component nearest the laser shutter. Keeps hand clear of LASER light path to avoid LASER burns on arms and hands. The following are very dangerous radiation hazards :

Direct radiation light as it leaves the laser shutter. Reflected radiation light which hit a surface and reflects back. Diffused radiation light which hits a surface and scattered.

Laser shutter

1.3.5 This tool is connected to HIGH VOLTAGES. 42VAC, 60VAC and 32KV are generated in the

laser device. The safety panels and interlocks should not be remove or bypassed or there is a risk of electrocution! The capacitors in the laser device holds tens of joules of energy up to 32KV. Capacitors voltages need to be completely discharge before any maintenance work on the power supplies. If you encounter any electrical malfunctions contact staff immediately.

1.3.6 The gas supplied to this machine contains a mixture of 5% fluorine and 95 % helium.

The 5% fluorine is further diluted in the laser with other gases. Inhalation or skin contact with halogen gasses should be avoided. Halogens can cause severe chemical and thermal burns to the respiratory track. Fluorine is characterized by an extremely stinging smell in very low concentrations (0.1ppm). If you suspect any problems with the gas supplies contact Nanofab staff immediately. USERS are required to read the following 20% and 100 % fluorine MSDS. http://www.chemadvisor.com/Matheson/database/msds/00244235000800003.PDF http://www.chemadvisor.com/Matheson/database/msds/MAT09920000220003.PDF

http://www.chemadvisor.com/Matheson/database/msds/00244235000800003.PDF

http://www.chemadvisor.com/Matheson/database/msds/MAT09920000220003.PDF


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Only trained Nanofab staff are allowed to open F2/He bottle and fill the gas line to the laser. After USER’s are finished only staff are allowed to evacuate the line and close the F2/He bottle.

1.3.7 USERS NOT allowed to FILL THE LASER TUBE or adjust the BUFFER gas Ne regulator , RARE gas Kr regulator, INERT gas He regulator or the HALOGEN F2/He gas regulators due to the risk of over pressurizing the laser tube and gas lines causing a leak.

BUFFER Ne (80psi) Rare Kr (80psi) INERT He (80psi)

1.3.8 Users cannot run the laser if EITHER facility ACID or SOLVENT exhaust are OFF. If you suspect an exhaust problem notify staff. If you’re already running the laser turn the laser OFF by pressing the RUN/STOP or BREAK button the keypad and notify staff immediately.

Acid exhaust OFF = 0 Solvent exhaust OFF = RED RUN/STOP button

1.3.9 Due to the fact a Nanofab staff member must power ON the COMPex 301 Excimer LASER, it can ONLY be used Monday-Friday’s from 8am to 5pm ( excluding holidays and UTA snow days).


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1.3.10 Read any posted NanoFAB Engineering Change Notices (ECN) for any hardware, process or safety changes before running the tool.

1.3.11 Note the location of emergency phone numbers and phone locations :

Emergency Exit Locations

1

Clean ZonesBuilding Clean Zone Legend.............Most Clean, Class 100.............Intermediate Clean, Class 10,000.............Lowest Clean, equipment, chase.............House Clean, building standard

Floorplan & Area Names

N

S

E W

Drawing Layers

3

Nanotechnology Research and Teaching Facility

8' wideopening Alley

12' wide

First Floor

Displayed Layers

UTA Cleanroom Floorplan.dsf

\usr2\UTA-Cleanroom\layouts

25 Apr 200024 ft : 1"

file:

path:

scale: last revised:

1st Level Floorplan

3' x 6.5'11.5' high

Raisedceiling forLN2 phaseseparator

(2 locations)

3' x 6.5'11.5' high

Floorplan Key:

....................= sliding glass door

KE

EP

CLE

AR

platform5' x 11'

ramp

5' x 8'

airshower

eva

p#2

eva

p#1

LN2

tank

LN2 service

LN2

fill

HPN2

gas

Men'sRoom

Women'sRoom

Building Cleanliness Zones

Location of emergency equipment.

First Aid

Fire Extinguisher

Phone Eye Wash

EXT

First Aid

WASH

EXT

EXT

EXTEXT

EXT

EXT

EXT

EXT

EXT

EXT

EXT EXT EXT

EXT

EXT

EXT

WASH

WASH

WASHWASH

First Aid

airshower

Entrance

Gowning

Teaching FabClass-10,000

Bay #1 Yellow Room, Class-100

Bay #2 Characterization, Class-100

Bay #3 Main Processing, Class-100

Bay #4 MBEClass-10,000

Chase #2

Chase #3

Chase #4

Chase #5

Entry ChaseEquipment Entrance

& Clean Storage

WorkroomLab #1

WorkroomLab #2

ToolShop

AssemblyArea

EastChase

Viewing Gallery

Alcove

AChaseFurnace

Park

Visitor Reception Lobby

TeachingYellow Room

4

Area Labels

Chase #1

ramp

5' x 8

'

North Side

Exit

East Side

Exit

Main

Lobby Exit

Main Lobby

Exit

1.3.12 Emergency Procedure :


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2.0 HARDWARE

2.1 All Lambda Physik excimer lasers use the NovaTube® technology. The NovaTube® has been conceived to eliminate the effects of corrosion and contamination.

2.2 Optimized electrode materials combined with an improved preionization scheme minimizes electrode erosion.

2.3 LASER gas replenishment can be controlled by processor when PGR mode selected.

2.4 LASER can run in High Voltage Constant Mode (HV CONST) or Energy Constant Mode (EGY CONST).

2.5 Automatic LASER tube purge and LASER tube fill.

2.6 LASER repetition rate 1Hz to 10Hz.

2.7 Pulse energy 500mj to 800 mj / average power 9-10 Watts/ nominal pulse duration 25ns/ 248nm λ .

3.0 REQUIREMENTS

3.1 Training

All users must be trained and authorized on the Lambda Physik COMPex 301 Excimer LASER to use this system. Training is supplied by a Nanofab staff member please contact the tool owner to schedule training.

3.2 System Restrictions

3.2.1 Users are not allowed to turn ON the laser main power, only Nanofab staff may do this.

3.2.2 Users are not allowed NOT allowed to FILL the laser, adjust the BUFFER gas Ne regulator , RARE gas Kr regulator, INERT gas He regulator or the HALOGEN F2/He gas regulators due to the risk of over pressurizing the laser tube and gas lines causing a leak.


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3.2.3 USER’s are not allowed to open F2/He bottle and fill the gas line to the laser. After USER’s are finished only staff are allowed to evacuate the line and close the F2/He bottle

3.2.4 Never run the LASER with the side panels removed or interlocks defeated.

3.2.5 If the keypad controller displays a system fault error code before or during a run

sequence notify Nanofab staff. 3.2.6 Before running LASER check vacuum pump exhaust tubing connection, facilities ACID

and Solvent exhaust are ON.

Vacuum pump exhaust tubing Acid exhaust ON = >0.75 Solvent exhaust ON = Green

3.2.7 IF the LASER has NOT ran for more than 5 days the LASER tube may need to be FLUSHED and have a NEW FILL (passivation) program performed. Nanofab Staff will make the final determination as to whether this is necessary.

Call staff if FLUSHED or NEW FILL program needs to be performed ( each line is flushed separately) and all gas bottle valves and final valves need to be CLOSED.

3.2.8 If the LASER has been idle and the gas has cooled down (cold start up) start the LASER with a repetition rate of 10 Hz and use High Voltage Constant Mode

(HV CONST) starting at 18 kV for 5 minutes then increase voltage in 2 kV increments to you reach your high voltage set point. If your need to run in Energy Constant Mode the switch modes after you have reach the high voltage set point and the gas is warmed up then change to Energy Constant Mode ( EGY CONTS) and enter the energy value you require ( 500mj – 800mj).

3.2.9 The maximum HIGH VOLTAGE allowed is 27kV. 3.2.10 The minimum HIGH VOLTAGE is 18kV ( Hardware-software configuration)

3.2.11 When the LASER is firing/running if your hear missing or extra pulses (the pulses will

sound like clicking noises) turn the LASER OFF and call staff to check Thyratron

voltages.


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3.2.12 USER’s are not allowed to adjust the optics package in the protective box, call staff for LASER alignments or adjustments.

4.0 OPERATING PROCEDURES

4.1. System Pre-Checks

4.1.1. Check to ensure LASER vacuum pump exhaust tubing connection, facilities ACID and Solvent exhaust is ON.

4.1.2. Check to ensure all unauthorized people leave Bay3.

4.1.3. Check to ensure the optical beam path of the LASER is completely closed..This includes the shutter to the LASER , the doors to the optical component and the door to the PLD vacuum chamber. Turn OFF the laser if any unauthorized person enters the Bay3 without safety eye ware.

4.1.4. Note the location of emergency phone numbers and phone locations :

Emergency Exit Locations

1

Clean ZonesBuilding Clean Zone Legend.............Most Clean, Class 100.............Intermediate Clean, Class 10,000.............Lowest Clean, equipment, chase.............House Clean, building standard

Floorplan & Area Names

N

S

E W

Drawing Layers

3

Nanotechnology Research and Teaching Facility

8' wideopening Alley

12' wide

First Floor

Displayed Layers

UTA Cleanroom Floorplan.dsf

\usr2\UTA-Cleanroom\layouts

25 Apr 200024 ft : 1"

file:

path:

scale: last revised:

1st Level Floorplan

3' x 6.5'11.5' high

Raisedceiling forLN2 phaseseparator

(2 locations)

3' x 6.5'11.5' high

Floorplan Key:

....................= sliding glass door

KE

EP

CLE

AR

platform5' x 11'

ram

p5' x 8

'

airshower

eva

p#2

eva

p#1

LN2

tank

LN2 service

LN2

fill

HPN2

gas

Men'sRoom

Women'sRoom

Building Cleanliness Zones

Location of emergency equipment.

First Aid

Fire Extinguisher

Phone Eye Wash

EXT

First Aid

WASH

EXT

EXT

EXTEXT

EXT

EXT

EXT

EXT

EXT

EXT

EXT EXT EXT

EXT

EXT

EXT

WASH

WASH

WASHWASH

First Aid

airshower

Entrance

Gowning

Teaching FabClass-10,000

Bay #1 Yellow Room, Class-100

Bay #2 Characterization, Class-100

Bay #3 Main Processing, Class-100

Bay #4 MBEClass-10,000

Chase #2

Chase #3

Chase #4

Chase #5

Entry ChaseEquipment Entrance

& Clean Storage

WorkroomLab #1

WorkroomLab #2

ToolShop

AssemblyArea

EastChase

Viewing Gallery

Alcove

AChaseFurnace

Park

Visitor Reception Lobby

TeachingYellow Room

4

Area Labels

Chase #1

ramp

5' x 8

'

North Side

Exit

East Side

Exit

Main

Lobby Exit

Main Lobby

Exit


10

4.1.5. Check to ensure safety eye ware is available for use (248 nm face shield or goggles)

4.2. Lambda Physik COMPex 301 Excimer LASER operation

4.2.1. If you have not completed the System Pre-Checks in steps 4.1.1 – 4.1.5 then you must complete those before proceeding.

4.2.2. Have a Nanofab staff member remove the LASER KEY from the lockbox. 4.2.3. The Nanofab staff member will turn the MAIN power switch from OFF to ON. The control lamp (24 VAC) and Power On lamp should now be illuminated.

4.2.4. The LASER controller will perform a self test. If any system errors are displayed call staff (i.e. Fatal Error, LWL-Data link ) After a successful self test the LASER warms up the thyratron for 8 minutes.

4.2.5. The warm up period can be used to check parameter settings, flush the lines and perform

new gas fill. Note:

Nanofab Staff will assess and decide if the LASER tube needs to be FLUSHED and the NEW FILL (passivation) program needs to be performed.

For the FLUSH program all gas bottle valves and final valves need to be CLOSED


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For the NEW FILL program all gas bottle valves and final valves need to be OPEN

Call staff if you believe the FLUSH or NEW FILL program needs to be performed (each line is flushed separately)

4.2.6. Check LASER parameter settings :

The Excimer Gas # 6 should be KrF. The LASER tube pressure # 5 should be 3100 – 3700 mB.

4.2.7. If Excimer gas # 6 display is incorrect press MENU//SEL button and use left or right arrow button to select menu = 2 248nm KrF then press ENTER button. The program will prompt Halogen = 70 mb press ENTER, Rare = 100 mb press ENTER, Buffer = 2930 mb press ENTER, Inert = 600 mb press ENTER.


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Select repetition rate 1Hz to 10 Hz (number of pulses per second 1/s) by pressing REPRATE button and then press numeric value using numbered key pad then press ENTER button.

Note : If the LASER has been idle and the gas has cooled down( cold start up) start the LASER with a repetition rate of 1 Hz to 10 Hz and use High Voltage Constant Mode

(HV CONST) starting at 18 kV for 5 minutes then increase voltage in 2 kV increments to you reach your high voltage set point. The maximum HIGH VOLTAGE allowed is 27kV. If your need to run in Energy Constant Mode the switch modes after you have reach the high voltage set point and the gas is warmed up then change to Energy Constant Mode ( EGY CONTS) and enter the energy value you require ( 500mj – 800mj).

To select running mode Energy Constant Mode with Partial Gas Replacement (EGY PGR ). Press press MODE button and use left or right arrow button to select EGY PGR then press ENTER button. In this mode output energy of the LASER pulses is constant by increasing the charging voltage HV and automatic gas replacement is performed if HV ≥ HVrepl

To select running mode High Voltage Constant Mode (HV) Press MODE button and use left or right arrow button to select HV then press ENTER .

The maximum HIGH VOLTAGE allowed is 27kV.

The minimum HIGH VOLTAGE is 18kV.

In this mode the output beam energy can be set at its maximum level when the precise beam energy in not necessary (mainly for maintenance / engineering troubleshooting).


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4.2.8. To enter beam energy press EGY button then type in new beam energy value (in mj) using numbered key pad then press ENTER button.

4.2.9. The LASER is now ready to turn on.

Put on the 248 nm UV goggles or UV face shields are available for putting the laser into operation. Ensure laser safety eye ware is worn by everyone operating on or near the laser and any unauthorized person without laser safety eye ware must LEAVE BAY3.

4.2.10. Turn on the LASER by pressing RUN/STOP button the press EXE button. Bay3 LASER danger warning light will go on but inform anyone entering this bay to leave. If you need to change the repetition rate refer to section 4.2.9 (Select repetition rate 1Hz to 10 Hz (number of pulses per second 1/s) by pressing REPRATE button and then press numeric

value using numbered key pad then press ENTER button)

If you need to change the high voltage HV refer to section 4.2.9 If you need to change the LASER running mode section 4.2.9

If you need to change the beam energy refer to section 4.2.10 After your LASER parameters are set and LASER firing sounds normal then OPEN LASER Shutter and begin your deposition.


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The LASER firing can be shut OFF by pressing the BREAK button or the RUN/STOP button

4.2.11. A well passivated LASER tube should be able to achieve your constant energy set point. If your energy set point and measured energy do not match contact Nanofab Staff to inspect the laser system.

Note :

While the LASER is firing/running if your hear missing or extra pulses (the pulses will sound like clicking noises) turn the LASER OFF and call staff to check Thyratron voltages

4.2.12. After your LASER process is completed Close the LASER shutter press RUN/STOP button to turn OFF the LASER. Bay3 LASER danger warning light should turn OFF.

4.2.13. Turn the Main POWER switch from its ON position to OFF and contact a Nanofab staff member to remove and secure the POWER KEY if you are finished running the system.

4.2.14. If your sample was heated during processing then allow it to cool to a safe level before venting the process chamber (typically < 50C) for sample removal.

4.2.15. Once the sample has been removed, close the vent valve, close the outer seal plate and pump the system back down to < 300 mT before closing the vacuum valves.

4.2.16. Turn OFF the system mechanical pump by turning OFF the pump power switch.

4.2.17. Enter the required information into the logbook, one entry per process run.


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5 RECIPES

5.1 LASER parameter settings will depend on the application.

5.1.1 Contact Nanofab staff about parameter changes before running the LASER.

5.1.2 Refer to sections 4.2.7 to 4.2.10 and the Lambda Physik COMPex 301 Maintenance manual.


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6 Gas Flush and Fill procedures

***Note*** The following procedures are to be performed by Nanofab staff

ONLY. If you feel that the laser tube needs to be recharged contact a staff

member to assess the PLD system. It is estimated that each FILL procedure

costs the Nanofab $150 in gas costs. Due to these high costs the laser should

only be recharged if the PLD system generates a low pressure fault OR if the

maximum laser output power is lower than desired for your process.

6.1.1 For the FLUSH program all gas bottle valves and final valves need to be CLOSED

6.1.2 For the NEW FILL program all gas bottle valves and final valves need to be OPEN

6.1.3 If a fill is needed, Go to Chase 4 and open the INERT, RARE and BUFFER gas bottle valves and final valves by turning the cylinder valves CCW two full turns. Open BUFFER (Ne) gas bottle valve and final valve. The delivery pressure should be 60 - 80 psi. Open RARE (Kr) gas bottle valve and final valve. The delivery pressure should be 60 - 80 psi. Open INERT (He) gas bottle valve and final valve. The delivery pressure should be 60 - 80 psi.

BUFFER (Ne) RARE (Kr) INERT (He)


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6.1.4 Perform the F2/He gas manifold purge and bottle open procedure to pressurize the gas line to the LASER and ensure the delivery regulator in the gas cabinet is set for 40 psi.

6.1.5 From the main system controller press the NEW FILL, ENTER & then EXE buttons

to begin the new fill process. The system vacuum pump will start automatically and begin evacuating the laser tube.

6.1.6 Once activated the NEW FILL process will take approximately 20 minutes to complete. The system will automatically evacuate the laser tube to a pre-programmed low pressure setpoint and then fill the 4 gases to specific pressure levels (3700 mB total) which will give the proper gas ratio for the excimer laser operation.

Halogen 70 mB (Florine)

Rare 100 mB (Krypton)

Buffer 2930 mB (Neon)

Inert 600 mB (Helium)


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6.1.7 When the NEW FILL process has completed the system controller screen will return to the normal run screen. Now return to service chase 4 and close the gas bottles that were opened earlier by turning the cylinder valves fully CW and then closing the final valves by turning them fully CW until they stop.

BUFFER (Ne) RARE (Kr) INERT (He)

6.1.8 The F2/He gas delivery line to the system should be left in an evacuated state for safety purposes. You must now perform the F2/He manual gas line discharge from the gas cabinet control panel. The F2/He cylinder valve may be left open and the pigtail from the cylinder to the gas regulator inlet valve can be left pressurized if you so desire.

lambda physik compex 301 excimer laser operating manual … lambda physik... · document: lambda...

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