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Strip Comparison Table

	Plasma Asher 3: Descum	Plasma Asher 4 (Clean)	Plasma Asher 5 (Dirty)	Resist strip	Lift-off
Purpose	Resist descum	Resist stripping Resist descum	Resist stripping Resist descum	Resist stripping	Metal lift-off
Method	Plasma ashing	Plasma ashing	Plasma ashing	Solvent & ultrasonication	Solvent & ultrasonication
Process: Gasses	O₂ (50 sccm)	O₂ (0-500 sccm) ₂ (0-500 sccm)	O₂ (0-500 sccm) N₂ (0-500 sccm) CF₄ (0-200 sccm)	NA	NA
Process: Power	10-100 W (10-100%)	150-1000 W	150-1000 W	NA	NA
Process: Solvent	NA	NA	NA	NMP (Remover 1165) IPA (rinsing agent)	NMP (Remover 1165) IPA (rinsing agent)
Substrate: Batch	Chips: several 50 mm wafer: several 100 mm wafer: 1	Chips: several 50 mm wafer: several 100 mm wafer: 1-25 150 mm wafer: 1-25 200 mm wafer: 1-25	Chips: several 50 mm wafer: several 100 mm wafer: 1-25 150 mm wafer: 1-25 200 mm wafer: 1-25	100 mm wafer: 1-25 150 mm wafer: 1-25	100 mm wafer: 1-25 150 mm wafer: 1-25
Substrate: Materials	No polymer substrates Silicon substrates III-V substrates Glass substrates Films, or patterned films, of any material except type IV (Pb, Te)	No metals No metal oxides No III-V materials Silicon substrates Glass substrates Polymer substrates Films, or patterned films, of resists/polymers	Silicon substrates III-V substrates Glass substrates Polymer substrates Films, or patterned films, of any material except type IV (Pb, Te)	No metals No metal oxides Silicon substrates III-V substrates Glass substrates Polymer substrates Films, or patterned films, of resists/polymers	Silicon substrates III-V substrates (only if clean) Glass substrates Films, or patterned films, of any material except type IV (Pb, Te)

Plasma Ashing process parameters

	Photoresist stripping	Descum after lithography	Surface treatment of plastic, ceramic and metal	Ashing of organic material
Process pressure	1.3 mbar	1.3 mbar	0.5-1.5 mbar	0.5-1.5 mbar
Process gases	O₂ (100 sccm) N₂ (100 sccm)	O₂ (100 sccm) N₂ (100 sccm)	O₂, CF₄, N₂ or their mixtures	O₂
Process power	1000 W	200 W	150-1000 W	1000 W or less for heat- sensitive materials
Process time	5-90 minutes	1-30 minutes	seconds to minutes	Between 0.5 and 20 hours, depending on the material
Batch size	1-25	1-25	1 wafer at a time	1 wafer at a time, use a container, e.g Petri dish

Plasma Asher 1

Plasma asher 1 was decommissioned 2024-12-02.

Information about decommissioned tool can be found here.

Plasma Asher 2

Plasma asher 2 was decommissioned 2024-12-02.

Information about decommissioned tool can be found here.

Plasma Asher 3: Descum

Plasma Asher 3: Descum is placed A-5

Product name: Diener Pico Plasma Asher
Year of purchase: 2014

The Plasma Asher 3: Descum is dedicated for resist descum, i.e. removal of remains resist traces after development. It has a small chamber, so you can only load a single 100 mm substrate, or a few smaller pieces.

In this machine, only Oxygen is used for processing.

Typical process parameters:
Process: Photoresist descumming
Pressure: 0.2-0.8 mbar
Gas: 45 sccm O₂
Power: 100%
Time: 1 -10 minutes (depending on photoresist type and thickness)

Other materials have not been tested.

The user manual, user APV, and contact information can be found in LabManager - requires login

Process Information

Detailed information about descum processing on Plasma asher 3: Descum can be found here.

Plasma Asher 4

Plasma asher 4 in cleanroom E-5.

Product name: PVA Tepla Gigabatch 380M
Year of purchase: 2024

The Plasma Asher 4 can be used for the following processes:

Photoresist stripping
Descumming
Surface cleaning
Removal of organic passivation layers and masks

Plasma asher 4 has the following material restrictions:

No metals allowed
No metal oxides allowed
No III-V materials allowed

The user manual, risk assessment, and contact information can be found in LabManager - requires login

Plasma Asher 5

Plasma asher 5 in cleanroom E-5.

Product name: PVA Tepla Gigabatch 380M
Year of purchase: 2024

The Plasma Asher 5 can be used for the following processes:

Photoresist stripping
Descumming
Surface cleaning
Removal of organic passivation layers and masks

Furthermore plasma processing using CF₄ in plasma asher 5 can be used for:

Etching of glass and ceramic
Etching of SiO₂, Si₃N₄, Si
Removal of polyimide layers

Typical stripping parameters

Resist: 1.5 µm AZ 5214E
Substrate: 100 mm Si
O₂: 100 sccm
N₂: 100 sccm
Pressure (DSC): 1.3 mbar
Power: 1000 W
Time (single wafer): 20 minutes
Time (full boat): 90 minutes

Plasma asher 5 can be used for almost every material, but if you have any doubt if your materials are compatible/allowed in plasma asher 5, feel free to ask the lithography group at Nanolab.

The user manual, risk assessment, and contact information can be found in LabManager - requires login

Process Information

Resist Strip

Resist strip bench in D-3

This resist strip is only for wafers without metal and SU-8.

There are one Remover 1165 bath for stripping and one IPA bath for rinsing.

Here are the main rules for resist strip use:

Place the wafers in a wafer holder and put them in the first bath for 10 min, this time is depending how much resist you have on the surface.
After the strip rinse your wafers in the IPA bath for 2-3 min.
Rinse your wafers for 4-5 min. in running water after stripping.

The user manual and contact information can be found in LabManager: Resist Strip - requires login

Overview of wet bench 06 and 07

	Resist Strip	Lift-off
General description	Wet stripping of resist	Lift-off process
Chemical solution	NMP Remover 1165	NMP Remover 1165
Process temperature	Up to 65°C	Up to 65°C
Batch size	1 - 25 wafers	1 - 25 wafers
Size of substrate	100 mm wafers 150 mm wafers	100 mm wafers 150 mm wafers
Allowed materials	Silicon Silicon Oxide Silicon Nitride Silicon Oxynitride	All metals except Type IV (Pb, Te)