https://nanyte.com/photoresists/ma-p-1240 · last updated 2026-09-28
- Manufacturer
- micro resist technology GmbH
- Tone
- positive
- Chemistry
- DNQ-novolak
- Thickness
- 4 µm
- Exposure dose
- 110 mJ/cm² (broadband, metered at 365 nm)
- Applications
- Etch mask · Electroplating / molding
- Substrate
- Resist
- Exposed
Spin coating
The manufacturer does not publish a spin curve for ma-P 1240.
- One tabulated point, not a sweep: the technical data table gives ma-P 1240 as 4 µm at 3000 rpm for 30 s, the single condition every grade in the series is listed at, and one anchor is not a curve.
- The sheet also plots film thickness against spin speed from 1000 to 6000 rpm for all six grades, but as smooth lines with no markers and no numeric table, so no values are published from it.
- Accel, dispense volume and edge-bead removal are not published.
- Adhesion
- Not addressed in this product sheet.
Soft bake
- Soft bake
- Not published — characterize on-tool
Exposure dose
The manufacturer publishes 110 mJ/cm² (broadband, metered at 365 nm). Dose scales with film thickness and depends on your optics, so treat it as a starting point and run a dose array.
- Dose at 405 nm
- Not published — characterize on-tool
- As published
- 110 mJ/cm² is the published dose for ma-P 1240, measured under broadband exposure with the meter reading the 365 nm line rather than specified as a monochromatic i-line dose.
SOURCE: Technical data table, p.1 of the ma-P 1200 series product sheet (ls.24.02.01), ma-P 1240 column
Development
Not published for this resist: Developer, Dilution, Time, Method, Rinse — characterize on-tool.
SOURCE: Unique features / Characteristics, p.1-2 of the ma-P 1200 series product sheet (ls.24.02.01)
Hard bake, etch & strip
- Etch resistance
- "High pattern stability in wet etch processes and acid and alkaline plating baths" and "Highly stable in dry etch processes e.g. CHF3, CF4, SF6" (Unique features, p.1).
Not published for this resist: Hard bake, Descum, Stripper, Storage — characterize on-tool.
Where it's used
Practical notes from the datasheet
ma-P 1240 is the four-micron grade of the standard ma-P 1200 series — not to be confused with ma-P 1240G, a separately formulated greyscale resist of similar thickness. The number to notice is the dose: at 110 mJ/cm² it is double what ma-P 1225 needs, a much larger jump than the 1.5 µm of extra film would suggest, so exposure time roughly doubles when stepping up to this grade. What that buys is a mould thick enough for substantial electroplating and an etch mask with real margin; the sheet's example is 3 µm lines on 5 µm spaces in a 4 µm film. Development is aqueous alkaline, and the sheet publishes no softbake, developer product or develop time.
Grades in this family
Other grades in the ma-P 1200 series line differ mainly in coating thickness:
Troubleshooting
Common failure modes for ma-P 1240, answered from the manufacturer's datasheet and application notes. These are starting points — your substrate, tooling and environment shift the specifics, so calibrate on-tool.
Bubbles show up in my 4 µm ma-P 1240 film during or right after exposure. What causes them?
MicroChemicals' trouble shooter explains it: exposing a DNQ positive resist releases nitrogen, and at 4 µm it has further to diffuse out than in the thin grades. It forms bubbles where the film still holds too much solvent (softbake too cool or too short), where adhesion to the substrate is weak, or where the dose arrives faster than the gas can escape. Fix the softbake and adhesion first; if bubbles remain, lower the lamp intensity and expose longer, or split the ma-P 1240 exposure (110 mJ/cm² broadband on the sheet) into several steps with pauses between.
SOURCE: MicroChemicals GmbH 'Photolithography Trouble Shooter'…
MicroChemicals GmbH 'Photolithography Trouble Shooter' application note — Bubbles in Resist Film after Exposure (Softbake Sufficient?, Sufficient Resist Adhesion?, Exposure Intensity Too High?, Resist Film Thickness Too High?), p.14–15; micro resist technology ma-P 1200 series product sheet (ls.24.02.01) — Technical data table, p.1
ma-P 1240 develops normally at first, then stalls before reaching the substrate. Dose or develop?
MicroChemicals' trouble shooter points at dose first. In a film thicker than the light's penetration depth, underexposure gives a normal development rate down to a certain depth, after which development almost stops, because the bottom of the film never received enough light. The sheet's 110 mJ/cm² for 4.0 µm is a broadband figure metered at 365 nm; a different lamp spectrum or tool needs its own dose series. The same note says DNQ resists need time to rehydrate after the softbake before exposure, and that the time grows with film thickness.
SOURCE: MicroChemicals GmbH 'Photolithography Trouble Shooter' —…
MicroChemicals GmbH 'Photolithography Trouble Shooter' — Sufficient Exposure Dose in the Case of Positive Resists? (thick resist films), p.7, and Sufficient Rehydration?, p.6; micro resist technology ma-P 1200 series product sheet (ls.24.02.01) — Technical data table, p.1
My ma-P 1240 mask rounds off or blisters in a CF4 or SF6 plasma etch. Why, when the sheet calls it dry-etch stable?
The sheet's claim is about etch resistance in CHF3, CF4 and SF6, not about what heat does to the pattern. MicroChemicals' trouble shooter explains both symptoms: if the wafer runs hot enough during the etch to pass the resist's softening point, the profile starts to round. Blistering has a separate cause: UV from the plasma can expose resist that was never exposed, releasing nitrogen that forms bubbles in the thermally softened film. Both depend on how hot the resist gets in the etch, so check that before blaming the resist.
SOURCE: micro resist technology ma-P 1200 series product sheet…
micro resist technology ma-P 1200 series product sheet (ls.24.02.01) — Unique features, p.1; MicroChemicals GmbH 'Photolithography Trouble Shooter' — Dry Etching: Common Problems (Resist Rounding/Flowing?, Bubbling of Resist?), p.16
The edge bead on my ma-P 1240 wafers is ruining contact at the aligner. What can I do?
The raised rim holds the mask off the rest of the wafer, and MicroChemicals' trouble shooter notes that such a gap widens exposed features and costs resolution. For round wafers without an automatic edge-bead station, it recommends dispensing an edge-bead solvent onto the rim at about 500 rpm and spinning it off at a higher speed — not acetone or another low-boiling solvent. Exposing and developing the bead away also works with a positive resist, at some risk of T-topping. For thick films, letting the coated wafer sit flat before the softbake keeps the bead from growing on the hotplate.
SOURCE: MicroChemicals GmbH 'Photolithography Trouble Shooter' (not a…
MicroChemicals GmbH 'Photolithography Trouble Shooter' (not a micro resist technology document) — Spin Coating: Edge Bead? (circular substrates; delay between coating and softbake; development of edge bead), p.2–3; Accidental Exposure of Positive Resists? (Proximity Gap), p.10; Gap between Photomask and Resist Surface?, p.12
Sources & disclaimer
- micro resist technology GmbH — ma-P 1240 datasheet (ls.24.02.01 (printed on both pages)) · accessed 2026-09-10
- https://kayakuam.com/products/ma-p-1200/ — kayakuam.com states 'ma-P 1200 is a positive tone DNQ/novolac based resist series'; the basis for classifying the ma-P 1200 grades as dnq-novolak.
Manufacturer datasheet values are starting points; optimal parameters depend on your substrate, equipment and environment. Product names and trademarks belong to their respective owners. NANYTE is not affiliated with the manufacturers listed. Last updated 2026-09-28.