Stepper Lithography Recipes

Below is a listing of stepper lithography recipes.  Based on your sample reflectivity, absorption, and surface topography the exposure time / focus offset parameters may vary. This listing is a guideline to get you started.  The recipes are tabulated to give you the values of the key parameters you will need to establish your recipe. For wafer cleaning and preparation including HMDS use, please refer to the cleaning and preparation section in the lithography section of this web site. Post develop bakes (not listed) are used to make the resist more etch resistant and depend on subsequent processes. Care should be taken with post development bakes as resist reflow can occur. Unless otherwise noted, all exposures are done on flat, silicon wafers.

Parameters are indicated in separate tables for each stepper system. Multiply the exposure times by 0.30 (from the 6300 system) to get a starting exposure time for the GCA Autostep200 system. You will need to do an exposure array to get precise times for the Autostep system. In general, the resolution achievable is ~ 100 nm smaller for the Autostep200 system.

 

Positive Resist

Unless otherwise noted, bakes are on hot plates. For recipes with CEM, the CEM is spun on after the first resist bake, exposure is then done, and the CEM is rinsed off with DI water before the PEB. CEM generally improves resolution and process tolerance at the expense of higher exposure time.

GCA 6300

Resist

Spin Cond.

Bake

Thickness

Exp. Time

Focus Offset

PEB

Developer

Dev. Time

Comment

SPR510A

4 krpm/30”

90°C/60”

~ 1.0 um

1.2”

0

105°C/60”

AZ300MIF

60”

0.5 um isolated lines

See SPR510A data file

SPR955CM0.9

3 krpm/30”

95°C/60”

~ 0.9 um

1.2”

0

110°C/60”

AZ300MIF

60”

0.5 um isolated lines

See SPR955CM data file

SPR955CM0.9

3 krpm/30”

95°C/60”

~ 0.9 um

3.0”

4

110°C/60”

AZ300MIF

60”

0.5 um isolated holes

Much longer exposure time for dense isolated holes

See SPR955CM data file

SPR955CM0.9

CEM365iS

3 krpm/30”

5 krpm/30”

95°C/90”

 

~ 0.9 um

 

2.2”

-10

110 C/60”

AZ300MIF

60”

0.35um isolated lines by SEM measurement. Higher exposure time due to CEM

See SPR955CM data file

SPR950-0.8

4 krpm/30”

95°C/60”

~ 0.8 um

1.0”

0

105°C/60”

AZ300MIF

60”

 

SPR955CM-1.8

4 krpm/30”

90°C/90”

~ 1.8 um

2.3”

0

110°C/90”

AZ300MIF

60”

See 955CM-1.8 data file

SPR220-3.0

2.5 krpm/30”

115°C/90”

~ 2.7 um

2.4”

10

115°C/90”

AZ300MIF

60”

See SPR220-3 Data File

SPR220-7.0

3.5 krpm/45”

115°C/120”

~ 7.0 um

4.5”

0

*50°C/60”

115°C/90”

AZ300MIF

120”

1.0 um isolated lines; 1.25 um isolated spaces

*Let sample sit in air for 20 minutes before PEB, step to 50°C for 60” first, then 115°C

See SPR220-7 Data File

Autostep200

Resist

Spin Cond.

Bake

Thickness

Exp. Time

Focus Offset

PEB

Developer

Dev. Time

Comment

SPR955CM-0.9

3 krpm/30”

95°C/90”

~ 0.9 um

0.35”

0

110°C/90”

AZ300MIF

60”

0.5um dense lines

See SPR955CM AS200

SPR955CM-0.9

3 krpm/30”

95°C/90”

~ 0.9 um

0.8”

0

110°C/90”

AZ300MIF

60”

0.5 um holes

SPR955CM-1.8

4 krpm/30”

95°C/90”

~ 1.8 um

0.4”

-1

110°C/90”

AZ300MIF

60”

See SPR955-1.8 AS200

 

Negative Resist

Unless otherwise noted, bakes are on hot plate. All flood exposures are done in broadband light using any contact aligner. Also, because the tone is negative, a shorter first exposure time will result in more undercut, which is desirable for single-layer lift-off processes. Under these conditions more develop time will also give more undercut.

GCA6300

Resist

Spin Cond.

Bake

Thickness

Exp. Time

Focus Offset

PEB

Flood

Developer

Dev. Time

Comment

AZ5214

6 krpm/30”

95°C/60”

~ 1 um

.2”

0

110°C/60”

60”

AZ300MIF

60”

0.5 um res. possible, but resist is sensitive to environment

nLOF5510

3 krpm/30”

90°C/60”

~ 0.93 um

.74”

-6

110°C/60”

0

AZ300MIF

60”

0.5 um line openings good dense or isolated

Use heated 1165 stripper for removal or lift-off

See nLOF5510 data file

nLOF2020

4 krpm/30”

110°C/60”

~ 2 um

.55”

-6

110°C/60”

0

AZ300MIF

90”

~ .85 um line opening/lift-off good. Isolated mesas can be smaller.

Use heated 1165 stripper for removal or lift-off Sensetive to PEB temp.

See nLOF2020 Data File

Autostep200

Resist

Spin Cond.

Bake

Thickness

Exp. Time

Focus Offset

PEB

Flood

Developer

Dev. Time

Comment

nLOF5510

3 krpm/30”

90°C/60”

~ 0.93 um

.25”

-1

110°C/60”

0

AZ300MIF

60”

0.4 um lines dense good

Use heated 1165 stripper for removal or lift-off

See nLOF5510 As200

 

2-Layer Lift-Off

Below are links to more detailed recipes using 2-layer processes for lift-off purposes. For a general description of lift-off techniques, please see the lift-off techniques page in the lithography section.

2-layer process with LOL2000 and SPR955 CM positive resist for 0.2 um and thinner lift-off

 

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