Specific Process Knowledge/Lithography/UVExposure

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UV Exposure Comparison Table

Equipment		Aligner: MA6-1	Aligner: MA6-2	Aligner: Maskless 01	Aligner: Maskless 02	Aligner: Maskless 03	Aligner: Maskless 04
Purpose		Top Side Alignment Back Side Alignment UV exposure OBS: this tool is in PolyFabLab	Top Side Alignment Back Side Alignment UV exposure (DUV exposure) Bond alignment	Top Side Alignment Maskless UV exposure	Top Side Alignment Back Side Alignment Maskless UV exposure	Top Side Alignment Back Side Alignment Maskless UV exposure	Top Side Alignment Maskless UV exposure Direct laser writing OBS: this tool is in PolyFabLab
Performance	Minimum feature size	~1 µm	~1 µm	~1 µm	~1 µm	~1 µm	~1 µm
	Alignment accuracy	TSA: ±2 µm BSA: ±5 µm	TSA: ±1 µm BSA: ±2 µm	±2 µm (±1 µm possible)	TSA: ± 0.5 µm BSA: ± 1 µm	TSA: ± 0.5 µm BSA: ± 1 µm	±1 µm
	Exposure light	350W Hg lamp i-line filter (365nm bandpass filter)	500W Hg-Xe lamp i-line filter (365nm bandpass filter)	365nm LED	375nm laser diode array	405nm laser diode array	365nm LED 405nm laser diode
	Exposure mode	Flood exposure Proximity Contact: Soft contact Hard contact Vacuum contact	Flood exposure Proximity Contact: Soft contact Hard contact Vacuum contact	Projection: Pneumatic auto-focus	Projection: Optical auto-focus Pneumatic auto-focus	Projection: Pneumatic auto-focus	Projection: Optical auto-focus Pneumatic auto-focus Direct laser writing: Optical auto-focus Pneumatic auto-focus
Substrates	Batch size	1 100 mm wafer	1 small sample, down to 10x10 mm2 1 50 mm wafer 1 100 mm wafer 1 150 mm wafer	1 small sample, down to 5x5 mm2 1 50 mm wafer 1 100 mm wafer 1 150 mm wafer	1 small sample, down to 3x3 mm2 1 50 mm wafer 1 100 mm wafer 1 150 mm wafer 1 200 mm wafer	1 small sample, down to 5x5 mm2 1 50 mm wafer 1 100 mm wafer 1 150 mm wafer	1 small sample, down to 3x3 mm2 1 50 mm wafer 1 100 mm wafer 1 150 mm wafer
	Allowed materials	All PolyFabLab materials	All cleanroom materials except copper and steel Dedicated chuck for III-V materials	All cleanroom materials	All cleanroom materials	All cleanroom materials	All PolyFabLab materials

Aligner: MA6-1

The Aligner: MA6-1 is located in PolyFabLab.

SUSS Mask Aligner MA6 is designed for high resolution photolithography. The 365nm exposure wavelength version is capable of 1.25 (1.0) um resolution in vacuum contact. All contact exposure programs (vacuum, hard, soft, proximity) are supplied. Two alignment options are available: top side alignment (TSA) with a split field or a video microscope and back side alignment (BSA) with BSA microscope. It is also possible to make IR- light alignment.

Training videos:
The training videos were made for MA6-2, but operation of MA6-1 is very similar as they are exactly the same model. Due to a different power supply, however, procedures for ignition and intensity control of the lamp is different for MA6-1. Please refer to the manual for the correct procedures.

Operation

Alignment

The user manual(s), quality control procedure(s) and results, and contact information can be found in LabManager - requires login

Exposure dose

Information on UV exposure dose

Process information

The Aligner: MA6-1 has an i-line notch filter installed. This results in an exposure light peak around 365nm with a FWHM of 7nm.

Link to information about alignment mark design and locations.

Equipment performance and process related parameters

Purpose		Alignment and UV exposure
Performance	Exposure mode	vacuum contact, hard contact, soft contact, proximity, flood exposure
	Exposure light/filters	365 nm (i-line) broadband (i-, g-, h-line), requires tool change (303 nm, requires tool change)
	Minimum structure size	down to 1.25µm
	Mask size	5x5 inch
	Alignment modes	Top side (TSA), ±2µm Backside (BSA), ±5µm
Substrates	Substrate size	Mask exposure and alignment: 100 mm wafers Flood exposure: samples up to 150 mm wafers
	Allowed materials	All PolyFabLab materials
	Batch	1

Aligner: MA6-2

The Aligner: MA6-2 is located in E-4.

The Süss MicroTek Mask Aligner MA6 is designed for high resolution photolithography. The 365nm exposure wavelength version is capable of 1.25 (1.0) um resolution in vacuum contact. All contact exposure programs (vacuum, low vacuum, hard, soft, proximity) are supplied. Two alignment options are available: top side alignment (TSA) with a split field or a video microscope and back side alignment (BSA) with BSA (video) microscope.

The aligner can also be used for bond alignment (for Wafer Bonder 02). Special training is required.

Training videos:

Operation

Alignment

The user manual, quality control procedures and results, user APVs, and contact information can be found in LabManager - requires login

Exposure dose

Information on UV exposure dose

Process information

The Aligner: MA6-2 has an i-line notch filter installed. This results in an exposure light peak at 365nm. Compared to exposure on the KS Aligner, the optimal dose should be very similar. The 500W Hg-Xe lamp also enables exposure in the DUV range around 240nm. This functionality is not established yet, partly due to safety concerns.

Link to information about alignment mark design and locations.

Quality Control (QC)

Quality Control (QC) for Aligner: MA6-2

The QC procedure for Aligner: MA6-2 - requires login The newest QC data for Aligner: MA6-2 - requires login QC Recipe: Manual intensity measurement Measurement area 100 mm Number of measurements 5 QC limits Aligner: MA6-2 Nominal intensity 11 mW/cm2 @ 365 nm Intensity deviation from nominal ≤5% Intensity non-uniformity ≤2% Power supply and/or lamp will be adjusted if intensity is outside the limit.

Alignment

Top Side Alignment:

• TSA microscope standard objectives: 5X, and 10X (20X available)
• TSA microscope special objectives: 11.25X offset (for smaller separation)

• Minimum distance between TSA microscope objectives: 33 mm (8 mm for special objectives)
  • Alignment of smaller separations is possible using the "scan microscope" function
• Maximum distance between TSA microscope objectives: 160 mm
• TSA microscope travel range: X +/- 25mm; Y +20mm / -75mm (towards flat)

BackSide Alignment:

• Minimum distance between BSA microscope objectives: 15 mm
• Maximum distance between BSA microscope objectives: 100 mm
• BSA microscope travel range: X +50mm / -16mm; Y +50mm / -20mm (towards flat)
• BSA chuck view ranges:
  • 2": X +/- 8-22mm; Y +/- 0-6mm
  • 4": X +/- 14-46mm; Y +/- 0-10mm
  • 6": X +/- 14-69mm; Y +/- 0-10mm (OBS: Max. separation of BSA microscopes is 100mm)

Microscope field of view (W x H, splitfield):

• TSA 5X
  • Oculars: 1.3mm x 2.6mm (Ø2.6mm full field)
  • Camera: 350µm x 500µm (700µm x 500µm full field)
• TSA 10X
  • Oculars: 0.6mm x 1.3mm (Ø1.3mm full field)
  • Camera: 150µm x 250µm (350µm x 250µm full field)
• TSA special
  • Oculars: 0.55mm x 1.1mm (Ø1.1mm full field)
  • Camera: 150µm x 200µm (300µm x 200µm full field)
• BSA camera
  • Low: 1.5mm x 2mm (3mm x 2mm full field)
  • High: 450µm x 650µm (950µm x 650µm full field)

Equipment performance and process related parameters

Purpose		Mask alignment and UV exposure, potentially DUV exposure 1) Bond alignment
Performance	Exposure mode	vacuum contact, hard contact, soft contact, proximity, flood exposure
	Exposure light/filters	broadband (i-, g-, h-line) 365 nm (i-line) "UV300" (280-350 nm) DUV (240 nm) 1)
	Minimum structure size	Typically 1.25 µm, possibly down to 0.8 µm 1)
	Mask size	5x5 inch 7x7 inch special holder for 4 x 2" designs on 5x5 inch
	Alignment modes	Top side (TSA), ±1µm (machine spec: ±2µm) Backside (BSA), ±2µm (machine spec: ±5µm)
Substrates	Substrate size	small pieces 1x1cm 50 mm wafers 100 mm wafers 150 mm wafers
	Allowed materials	All cleanroom materials except copper and steel Dedicated chuck for III-V materials
	Batch	1

¹⁾ Not available yet. Requires tool change. Would require safety investigation (and a dedicated project) to become available.

Light intensity and uniformity after lamp ignition

Light intensity and uniformity after lamp ignition. CP is constant power mode, CI is constant intensity mode. The accept limits for the CI mode is ±5%, the accept limit for the non-uniformity is 2%. CP mode has no accept limit.

The lamp requires about 15 minutes of on-time after lamp ignition, before the light output has stabilized, and users using the constant power mode should always wait for 15 minutes after ignition, before starting processing.

If users use the constant intensity mode, this waiting time is not necessary, since the internal light sensor automatically adjusts the output to match the setpoint value.

The non-uniformity of the light, in CI mode, is unaffected by the stabilization time.

Aligner: Maskless 01

Aligner: Maskless 01 is located in E-4.

The logon password for the PC is "mla" (without quotation marks).

The MLA 100 Maskless Aligner located in the E-4 cleanroom is a direct exposure lithography tool installed in 2017. It is a UV LED exposure system, that exposes the patterns directly on photosensitive resists on chips, 2, 4, and 6 inch substrates, without prior fabrication of the mask. The system offers top side alignment with high accuracy.

Link to information about alignment mark design.

The user manual and contact information can be found in LabManager:

Equipment info in LabManager - requires login

Exposure dose and defocus

Information on UV exposure dose

Process information

• Exposure technology
• Process parameters
• Substrate positioning
• Alignment
• Optimal use of the maskless aligner

Quality Control (QC)

Quality Control (QC) for Aligner: Maskless 01 (MLA1) - Dose and Defoc

The QC procedure for Aligner: Maskless 01 (MLA1) - requires login The newest QC data for Aligner: Maskless 01 (MLA1) - requires login QC: Dose and defocus test on 1.5µm AZ5214E QC limits Dose test Step size is 5 mJ/cm2 Test range is last QC value ± 10 mJ/cm2 (5 steps total) none Defoc test Step size is 1 defoc Test range is last QC value ± 4 (5 steps total) none

Quality Control (QC) for Aligner: Maskless 01 (MLA1) - Alignment

The QC procedure for Aligner: Maskless 01 (MLA1) - requires login The newest QC data for Aligner: Maskless 01 (MLA1) - requires login QC Recipe: Alignment accuracy test QC limits Topside alignment Expose an overlay design after automatic alignment to 4 alignment marks using the High Res camera and applying scaling and shearing. Alignment accuracy in 9 points across a 100mm wafer is measured, the average alignment error is reported. Must be better than 1µm Camera offsets will be adjusted if alignment error is outside the limit.

Equipment performance and process related parameters

Purpose		Alignment and UV exposure
Performance	Exposure mode	Projection
	Exposure light	365nm (LED), FWHM=8nm
	Focusing method	Pneumatic
	Minimum structure size	down to 1µm
	Design formats	GDS-II CIF DXF Gerber HIMT format
	Alignment modes	Top side only, ±2µm (±1µm can be achieved)
Substrates	Substrate size	maximum writing area: 125x125 mm2 150 mm wafer 100 mm wafer 50 mm wafer pieces down to 5x5 mm2
	Allowed materials	All cleanroom materials Total height variation across the substrate must be less than ±40 µm - including wafer bow
	Batch	1

Aligner: Maskless 02

Aligner: Maskless 02 is located in E-5.

MLA150 WMII maskless aligner from Heidelberg Instruments GmbH (installed 2019 as WMI (0.6µm resolution), rebuilt to WMII 2023).

Special features

• Optical Autofocus
• Backside Alignment
• Basic Gray Scale Exposure
• Advanced Field Alignment Mode for alignment to individual chips/devices on the substrate
• High Aspect Ratio Mode for exposure of thick resists
• 200 x 200 mm exposure field
• Separate conversion PC

Link to information about alignment mark design.

Training videos

Equipment info in LabManager - requires login

Exposure dose and defocus

Information on UV exposure dose

Process information

• Exposure technology
• Process Parameters
• Features
• Alignment

Quality Control (QC)

Quality Control (QC) for Aligner: Maskless 02 (MLA2) - Dose and Defoc

The QC procedure for Aligner: Maskless 02 (MLA2) - requires login The newest QC data for Aligner: Maskless 02 (MLA2) - requires login QC Recipe: Dose and defocus test on 1.5µm AZ5214E Dose test Last QC value ± 20 mJ/cm2 (9 steps total) Defoc test Last QC value ± 8 (9 steps total) QC limits Aligner: Maskless 02 (MLA2) Dose none Defoc none Dose and defoc values are reported in the QC data sheet.

Quality Control (QC) for Aligner: Maskless 02 (MLA2) - Alignment

The QC procedure for Aligner: Maskless 02 (MLA2) - requires login The newest QC data for Aligner: Maskless 02 (MLA2) - requires login QC Recipe: Alignment accuracy test Topside alignment Expose an overlay design after automatic alignment to 4 alignment marks using the High Res camera and applying scaling and shearing. Alignment accuracy in 9 points across a 100mm wafer is measured, the average alignment error is reported. Backside alignment Expose an overlay design after automatic alignment to 4 backside alignment marks and applying scaling and shearing. Rotate the wafer 180° and repeat. Alignment accuracy in 9 points across a 100mm wafer is measured, half the average alignment error is reported. QC limits Aligner: Maskless 02 (MLA2) Topside alignment error >0.5µm Backside alignment error >1µm Camera offsets will be adjusted if alignment error is outside the limit.

Equipment performance and process related parameters

Purpose		Alignment and UV exposure
Performance	Exposure mode	Projection
	Exposure light	375 nm (laser diode arrays)
	Focusing method	Optical Pneumatic
	Minimum structure size	down to 1 µm
	Design formats	GDS-II CIF DXF Gerber HIMT format
	Alignment modes	Top side alignment, ±0.5µm Backside alignment, ±1.0µm Field alignment (chip-by-chip TSA), ±0.25µm (within 5x5mm2 area)
Substrates	Substrate size	maximum writing area: 200x200 mm2 200 mm wafer 150 mm wafer 100 mm wafer 50 mm wafer pieces down to 3x3 mm2 1)
	Allowed materials	All cleanroom materials Total height variation across the substrate must be less than ±90 µm - including wafer bow
	Batch	1

¹⁾ with optical autofocus

Aligner: Maskless 03

Aligner: Maskless 03 is located in E-5.

MLA150 WMII maskless aligner from Heidelberg Instruments GmbH, installed 2020.

Special features:

• Backside Alignment
• Advanced Field Alignment Mode for alignment to individual chips/devices on the substrate
• Separate conversion PC (Power PC)

Link to information about alignment mark design.

Training videos

Equipment info in LabManager - requires login

Exposure dose and defocus

Information on UV exposure dose

Process information

• Exposure technology
• Process Parameters
• Features
• Alignment

Quality Control (QC)

Quality Control (QC) for Aligner: Maskless 03 (MLA3) - Dose and Defoc

The QC procedure for Aligner: Maskless 03 (MLA3) - requires login The newest QC data for Aligner: Maskless 03 (MLA3) - requires login QC Recipe: Dose and defocus test on 1.5µm AZ5214E Dose test Last QC value ± 20 mJ/cm2 (9 steps total) Defoc test Last QC value ± 8 (9 steps total) QC limits Aligner: Maskless 03 (MLA3) Dose none Defoc none Dose and defoc values are reported in the QC data sheet.

Quality Control (QC) for Aligner: Maskless 03 (MLA3) - Alignment

The QC procedure for Aligner: Maskless 03 (MLA3) - requires login The newest QC data for Aligner: Maskless 03 (MLA3) - requires login QC Recipe: Alignment accuracy test Topside alignment Expose an overlay design after automatic alignment to 4 alignment marks using the High Res camera and applying scaling and shearing. Alignment accuracy in 9 points across a 100mm wafer is measured, the average alignment error is reported. Backside alignment Expose an overlay design after automatic alignment to 4 backside alignment marks and applying scaling and shearing. Rotate the wafer 180° and repeat. Alignment accuracy in 9 points across a 100mm wafer is measured, half the average alignment error is reported. QC limits Aligner: Maskless 03 (MLA3) Topside alignment error >0.5µm Backside alignment error >1µm Camera offsets will be adjusted if alignment error is outside the limit.

Equipment performance and process related parameters

Purpose		Alignment and UV exposure
Performance	Exposure mode	Projection
	Exposure light	405nm (laser diode array)
	Focusing method	Pneumatic
	Minimum structure size	down to 1 µm
	Design formats	GDS-II CIF DXF Gerber HIMT format
	Alignment modes	Top side alignment, ±0.5µm Backside alignment, ±1.0µm Field alignment (chip-by-chip TSA), ±0.25µm (within 5x5mm2 area)
Substrates	Substrate size	maximum writing area: 150x150 mm2 150 mm wafer 100 mm wafer 50 mm wafer pieces down to 5x5 mm2
	Allowed materials	All cleanroom materials Total height variation across the substrate must be less than ±90 µm - including wafer bow
	Batch	1

Aligner: Maskless 04

Aligner: Maskless 04 is located in PolyFabLab in building 347.

The logon password for the PC is "mla" (without quotation marks).

The µMLA Tabletop Maskless Aligner from Heidelberg, located in PolyFabLab in building 347, is a direct exposure lithography tool installed in 2024. It is a UV exposure system, that exposes the patterns directly on photosensitive resists on chips, 2, 4, and 6 inch substrates, without prior fabrication of a mask. The system offers top side alignment with good accuracy.

Link to information about alignment mark design.

The user manual and contact information can be found in LabManager:

Equipment info in LabManager - requires login

Process information

• Exposure technology
• Process parameters
• Substrate positioning
• Alignment

Equipment performance and process related parameters

Purpose		Alignment and UV exposure
Performance	Exposure mode	Projection (Raster mode) Direct laser writing (Vector mode)
	Exposure light	365nm (LED) for projection 405nm (diode laser) for direct laser writing
	Focusing method	Pneumatic or Optical
	Minimum structure size	Down to 1µm
	Design formats	GDS-II CIF DXF Gerber HIMT format
	Alignment modes	Top side only, ±1µm
Substrates	Substrate size	maximum writing area: 150x150 mm2 150 mm wafer 100 mm wafer 50 mm wafer pieces down to 3x3 mm2 with optical autofocus
	Allowed materials	All PolyFabLab materials with sufficient stiffness and flatness. Total height variation across the substrate must be less than ±80 µm - including wafer bow
	Batch	1