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LEFT: schematic of the inductively coupled plasma (ICP) argon ion source, user sample (red) is placed to the right of the accelerator grid. “Neut.” Refers to the neutralizer. RIGHT: schematic of the Hiden Ion Milling Probe using Secondary Ion Mass Spectrometry (SIMS) for etch End Point Detection (EPD). 

Page Properties
idInfo


Questions & Troubleshooting

References

Presentation: Introduction to AJA Ion Mill (Fab Forum, Feb 2019)

View file
nameKRI AC DISCHARGE CONTROLLER MANUAL AC1006_V2.pdf
height250
View file
nameKRI Auto Controller Manual RFAC1 LFN Manual.pdf
height250
View file
nameKRI Emission Controller Manual EC12002_V2.pdf
height250
View file
nameKRI Ion Optics Controller Manual 9007-0007_IOC15XX_01_VD.PDF
height250
View file
nameKRI LFN2000 NEUTRALIZER MANUAL_S_VB.PDF
height250
View file
nameKRI RF grid 7117-Certificate.pdf
height250
View file
nameKRI RFICP 140 ION SOURCE and ion optics MANUAL 9007-RF-1401_VC.pdf
height250
View file
nameMKS 937B gauge controller manual.pdf
height250
View file
nameSeren RF power supply manual_RLX01_V2_02.pdf
height250
View file
nameEBARA TMP MANUAL ME_PU_EMT2200MK/3300MK-B_STD(CN)_R0 sec pa.pdf
height250
View file
nameIMP End Point Detector User Manual.pdf
height250
View file
nameMASsoft Professional Manual IMP-EPD.pdf
height250
View file
nameAJA logbook.pdf
height250
View file
nameVAT gate valve series 11.pdf
height250
View file
nameMKS 974 gauge Manual - REV C.PDF
height250

Note
titleCOVID-19 resources at Birck

https://www.purdue.edu/discoverypark/birck/for-birck-users/covid/index.php

Image Removed

Image Removed

LEFT: schematic of the inductively coupled plasma (ICP) argon ion source, user sample (red) is placed to the right of the accelerator grid. “Neut.” Refers to the neutralizer. RIGHT: schematic of the Hiden Ion Milling Probe using Secondary Ion Mass Spectrometry (SIMS) for etch End Point Detection (EPD). 

Page Properties
idInfo
iLab NameC - AJA ICP Argon Ion Mill Etcher
iLab KioskBRK Etch Core
FICSunil Bhave
OwnerNeil Dilley
LocationCleanroom - Q Bay
Max. Wafer6"/150 mm
Staff PageAJA ICP Argon Ion Mill Etcher - Staff
iLab NameC - AJA ICP Argon Ion Mill Etcher
iLab KioskBRK Etch Core
FICSunil Bhave
OwnerNeil DilleyNick Glassmaker
LocationCleanroom - Q Bay
Max. Wafer6"/150 mm
Staff PageAJA ICP Argon Ion Mill Etcher - Staff

Tool Highlights

  • Direct physical milling of thin and thick films using argon atoms.
  • Ion beam source : inductively-coupled argon plasma, accelerated up to 900 V in a 14cm broad beam with currents up to 620 mA (Kaufman & Robinson, Inc.).
  • Ar+ ions neutralized using a matched electron beam current before reaching the sample.
  • water-cooled rotating sample carrier can be oriented 0-90 degrees from normal beam incidence.
  • Secondary ion mass spectrometer (SIMS) mounted on the system can be used for manual or automatic endpoint detection (EPD) of milled material by discerning elements based on charge/mass ratio of positive ions (Hiden Analytical).
  • Sample load-lock system saves time with processing.
Page Properties
idEtch_Capabilities
TypeMaterialsRestricted MaterialsAvailable GasesMax RF PowerWafer SizeICP Ion Milloxides, metals, polymersAuAr900 W6"
Page Properties
idFunctionality
StatusUPEstimated Fix Date and Comment
Responding StaffNeil
Table of Content Zone
locationtop
styledisc

Table of Contents
outlinetrue
indent25px
stylenone

Sample Requirements and Preparation

The shared carrier and mask wafers are dirty since they collect all the sputtered material from users' samples.

If you care about contamination of your sample due to re-sputtering of material, you need to provide your own carrier and masks.

About etching gold (Au): please discuss with Neil or the BNC staff in charge before etching Au. 

Sample chuck cooling during etch: Note that thick films require high etch rates (and hence high amounts of heating), so this may mean one needs to load the sample directly on the chuck by venting the chamber (instead of using load lock). This will permit users to apply more torque and get better cooling of the chuck. However, it requires special training.

For EPD, note that argon atomic mass is the same as MgO, so the EPD is not able to sense (ionized) MgO in the large Ar ion background.

Standard Operating Procedure

View file
nameSOP - AJA ion mill.pdf
height250

Process Library

Recipes should be submitted at bottom of this page in comments section or emailed to Neil Dilley ndilley@purdue.edu ; they need to include:

  • mask type and how to prepare it (e.g., photoresist type, spin speed, bake temp/time, exposure, development)
  • milling 
    • program # 
    • duty cycle (on/off times)
    • angle of substrate

From Qi Wang

Mask: Photoresist AZ9260/2000rpm/bake at 110C for 3min
Material to etch: SmNiO3
Depth: 50nm
Process used in PhaseIIJ software (program #, angle, and milling duty cycle): Program 3_-30deg_2min
A 5min ultrasonic cleaning in acetone could remove most of the photo resist. The stubborn residue near pattern edges was able to be removed by soaking in remover-PG at 80C for 1h and ultrasonic cleaning for 2min. 

From Sen Dai, deep etching ~0.5um of LiNbO3 (special SOP, ask staff)

Mask: SPR220 or any PR that fits your needs.
Our requirement is that the PR is at least ~2x thicker than the material you want to etch so that it will not be etched through.
If using SPR220:
Spin at 3000rpm, then bake 115degree 90sec. This will produce 4 um film. Expose your pattern at 350mJ/cm2. Develop using MF24A 60sec. 
Milling: program #3 (VB=600 V, (mill 3'30" / cool 12' ) repeated 8x.

From Chengzi Huang

Mask: SPR220-4.5 as the photoresist, spin speed 5000rpm, bake 115C for 90s.

Milling: 50nm/40nm/150nm Pd/BYZ/NNO with program 3, angle -30, 3 cycles of (2 min etch +12min cooling)

When etching Si, PR residuals can be easily removed by 5s ultrasonic cleaning in acetone. When etching the above Pd/BYZ/NNO stack, post cleaning requires 1min ultrasonic cleaning + 5min branson asher O2 plasma clean.

From Steve Novakov (John Heron group, U. Michigan)

Mask: SPR 220-3.0 on the spinner with the following recipe: Step 1. 500 rpm, 500 rpm/s, 5s  Step 2: 4500 rpm, 1250 rpm/s, 35s. Bake on hotplate at 90 C for 2 minutes. This may not be 100% mandatory for projection exposure tools and large devices, but is mandatory for contact mask exposure and small devices. NOTE: The final spin speed can be varied/tuned. I prefer as thin of a resist as possible to shorten development/exposure time. However, in the case of TMD’s, having a modest edge/corner bead serves as an additional protective element, reducing pressure on the film from the mask aligner, etc.

Milling: Al2O3 |  Bi2Se3 (~ 10 nm)| MnSe (~ 5 nm)| Se  (~ 10 nm) : etch to Al2O3 substrate. Program #2, -30 degrees. Duty cycle milling on 30sec / off 30 sec, for a total milling time of 4 minutes until Bi and Se signals level off in EPD. Sample was likely milled after 2 minutes but the Bi/Se trends at EPD were tailing off slowly. 

More complete description of their litho/liftoff process is here.

Ozan Erturk (Bhave group)

PMN-PT Etching

Mask: SPR220-7 at 4000rpm, bake 110C for 30 sec hold ~1cm above the hotplate then  90s in contact.

Milling: Si/PMN-PT/ PR with program 3, angle -14, 2 cycles of ( 210 sec etch +7min cooling)  + angle -70, 2 cycles of ( 210 sec etch +7min cooling) 
This package that contains 2 cycles of -14 degree followed by -70 degree etch can be repeated as many times required to achieve the desired vertical depth.

Etched material: 1.8um  (Etch rate ~52nm/min)

Etched PR: ~1.2um (Selectivity is 1:1.5  PR : PMN-PT)

Note: selectivity significantly decreases for longer cycle times. For deeper etch depths, it is recommended to perform batches of 10 cycles with ~2hrs of cooling in between.

Si Etching

Mask: SPR220-7 at 4000rpm, bake 110C for 30 sec hold ~1cm above the hotplate then  90s in contact.
Milling: Si/PR with program 3, angle -14, 10 cycles of ( 150 sec etch +7min cooling) 

Etched material: 1.1um  (Etch rate ~45nm/min)

Etched PR: ~1.1um (Selectivity is 1:1  PR : Si)

Info LinksInternal | Staff



Tool Highlights

  • Direct physical milling of thin and thick films using argon atoms.
  • Ion beam source : inductively-coupled argon plasma, accelerated up to 900 V in a 14cm broad beam with currents up to 620 mA (Kaufman & Robinson, Inc.).
  • Ar+ ions neutralized using a matched electron beam current before reaching the sample.
  • water-cooled rotating sample carrier can be oriented 0-90 degrees from normal beam incidence.
  • Secondary ion mass spectrometer (SIMS) mounted on the system can be used for manual or automatic endpoint detection (EPD) of milled material by discerning elements based on charge/mass ratio of positive ions (Hiden Analytical).
  • Sample load-lock system saves time with processing.
Page Properties
idEtch_Capabilities


TypeMaterialsRestricted MaterialsAvailable GasesMax RF PowerWafer Size
ICP Ion Milloxides, metals, polymersAuAr900 W6"




iLab KioskeLog: SubmiteLog: View/EditReport Problem


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Insert excerpt
eLog - AJA ICP Argon Ion Mill Etcher
eLog - AJA ICP Argon Ion Mill Etcher
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Page Properties
idFunctionality


StatusUP


Estimated Fix Date and Comment


Responding StaffNeilNick G.




Table of Content Zone
locationtop
styledisc

Table of Contents
outlinetrue
indent25px
stylenone


Sample Requirements and Preparation

The shared carrier and mask wafers are dirty since they collect all the sputtered material from users' samples.

If you care about contamination of your sample due to re-sputtering of material, you need to provide your own carrier and masks.

About etching gold (Au): please discuss with Neil or the BNC staff in charge before etching Au. 

Sample chuck cooling during etch: Note that thick films require high etch rates (and hence high amounts of heating), so this may mean one needs to load the sample directly on the chuck by venting the chamber (instead of using load lock). This will permit users to apply more torque and get better cooling of the chuck. However, it requires special training.

For EPD, note that argon atomic mass is the same as MgO, so the EPD is not able to sense (ionized) MgO in the large Ar ion background.

Standard Operating Procedure

View file
nameSOP - AJA ion mill.pdf
height250


Process Library

Recipes should be submitted at bottom of this page in comments section or emailed to Neil Dilley ndilley@purdue.edu ; they need to include:

  • mask type and how to prepare it (e.g., photoresist type, spin speed, bake temp/time, exposure, development)
  • milling 
    • program # 
    • duty cycle (on/off times)
    • angle of substrate

From Qi Wang

Mask: Photoresist AZ9260/2000rpm/bake at 110C for 3min
Material to etch: SmNiO3
Depth: 50nm
Process used in PhaseIIJ software (program #, angle, and milling duty cycle): Program 3_-30deg_2min
A 5min ultrasonic cleaning in acetone could remove most of the photo resist. The stubborn residue near pattern edges was able to be removed by soaking in remover-PG at 80C for 1h and ultrasonic cleaning for 2min. 

From Sen Dai, deep etching ~0.5um of LiNbO3 (special SOP, ask staff)

Mask: SPR220 or any PR that fits your needs.
Our requirement is that the PR is at least ~2x thicker than the material you want to etch so that it will not be etched through.
If using SPR220:
Spin at 3000rpm, then bake 115degree 90sec. This will produce 4 um film. Expose your pattern at 350mJ/cm2. Develop using MF24A 60sec. 
Milling: program #3 (VB=600 V, (mill 3'30" / cool 12' ) repeated 8x.

From Chengzi Huang

Mask: SPR220-4.5 as the photoresist, spin speed 5000rpm, bake 115C for 90s.

Milling: 50nm/40nm/150nm Pd/BYZ/NNO with program 3, angle -30, 3 cycles of (2 min etch +12min cooling)

When etching Si, PR residuals can be easily removed by 5s ultrasonic cleaning in acetone. When etching the above Pd/BYZ/NNO stack, post cleaning requires 1min ultrasonic cleaning + 5min branson asher O2 plasma clean.

From Steve Novakov (John Heron group, U. Michigan)

Mask: SPR 220-3.0 on the spinner with the following recipe: Step 1. 500 rpm, 500 rpm/s, 5s  Step 2: 4500 rpm, 1250 rpm/s, 35s. Bake on hotplate at 90 C for 2 minutes. This may not be 100% mandatory for projection exposure tools and large devices, but is mandatory for contact mask exposure and small devices. NOTE: The final spin speed can be varied/tuned. I prefer as thin of a resist as possible to shorten development/exposure time. However, in the case of TMD’s, having a modest edge/corner bead serves as an additional protective element, reducing pressure on the film from the mask aligner, etc.

Milling: Al2O3 |  Bi2Se3 (~ 10 nm)| MnSe (~ 5 nm)| Se  (~ 10 nm) : etch to Al2O3 substrate. Program #2, -30 degrees. Duty cycle milling on 30sec / off 30 sec, for a total milling time of 4 minutes until Bi and Se signals level off in EPD. Sample was likely milled after 2 minutes but the Bi/Se trends at EPD were tailing off slowly. 

More complete description of their litho/liftoff process is here.

Ozan Erturk (Bhave group)

PMN-PT Etching

Mask: SPR220-7 at 4000rpm, bake 110C for 30 sec hold ~1cm above the hotplate then  90s in contact.

Milling: Si/PMN-PT/ PR with program 3, angle -14, 2 cycles of ( 210 sec etch +7min cooling)  + angle -70, 2 cycles of ( 210 sec etch +7min cooling) 
This package that contains 2 cycles of -14 degree followed by -70 degree etch can be repeated as many times required to achieve the desired vertical depth.

Etched material: 1.8um  (Etch rate ~52nm/min)

Etched PR: ~1.2um (Selectivity is 1:1.5  PR : PMN-PT)

Note: selectivity significantly decreases for longer cycle times. For deeper etch depths, it is recommended to perform batches of 10 cycles with ~2hrs of cooling in between.

Si Etching

Mask: SPR220-7 at 4000rpm, bake 110C for 30 sec hold ~1cm above the hotplate then  90s in contact.
Milling: Si/PR with program 3, angle -14, 10 cycles of ( 150 sec etch +7min cooling) 

Etched material: 1.1um  (Etch rate ~45nm/min)

Etched PR: ~1.1um (Selectivity is 1:1  PR : Si)See Internal Resources page. 


Questions & Troubleshooting



References

Presentation: Introduction to AJA Ion Mill (Fab Forum, Feb 2019)

View file
nameKRI AC DISCHARGE CONTROLLER MANUAL AC1006_V2.pdf
height250
View file
nameKRI Auto Controller Manual RFAC1 LFN Manual.pdf
height250
View file
nameKRI Emission Controller Manual EC12002_V2.pdf
height250
View file
nameKRI Ion Optics Controller Manual 9007-0007_IOC15XX_01_VD.PDF
height250
View file
nameKRI LFN2000 NEUTRALIZER MANUAL_S_VB.PDF
height250
View file
nameKRI RF grid 7117-Certificate.pdf
height250
View file
nameKRI RFICP 140 ION SOURCE and ion optics MANUAL 9007-RF-1401_VC.pdf
height250
View file
nameMKS 937B gauge controller manual.pdf
height250
View file
nameSeren RF power supply manual_RLX01_V2_02.pdf
height250
View file
nameEBARA TMP MANUAL ME_PU_EMT2200MK/3300MK-B_STD(CN)_R0 sec pa.pdf
height250
View file
nameIMP End Point Detector User Manual.pdf
height250
View file
nameMASsoft Professional Manual IMP-EPD.pdf
height250
View file
nameAJA logbook.pdf
height250
View file
nameVAT gate valve series 11.pdf
height250
View file
nameMKS 974 gauge Manual - REV C.PDF
height250