https://nanyte.com/photoresists/kmpr-1050 · last updated 2026-07-26
- Manufacturer
- Kayaku Microchem (MicroChem)
- Tone
- negative
- Chemistry
- Epoxy (SU-8 type)
- Thickness
- 34–115 µm
- Developer
- 2.38% TMAH (0.26N) aqueous alkaline developer (primary); SU-8 Developer (solvent-based) is also usable as an alternative
- Applications
- High aspect ratio · MEMS structural · Electroplating / molding · Etch mask
Cross-checked — two independent extractions agree on the spin curve and the single-value figures.
- Substrate
- Resist
- Exposed
Spin coating
Data points
| Series | rpm | µm | Published dose |
|---|---|---|---|
| KMPR 1050 | 1000 | 101 | — |
| 2000 | 68 | 1070–1465 mJ/cm² · 56–80 µm row | |
| 3000 | 51 | 665–1055 mJ/cm² · 31–55 µm row 1070–1465 mJ/cm² · 56–80 µm row within 10 % of a bracket edge | |
| 4000 | 44 | 665–1055 mJ/cm² · 31–55 µm row | |
| KMPR 1050 (23°C Japan & Asia) | 1000 | 115 | — |
| 2000 | 67 | 1070–1465 mJ/cm² · 56–80 µm row | |
| 3000 | 47 | 665–1055 mJ/cm² · 31–55 µm row | |
| 4000 | 34 | 665–1055 mJ/cm² · 31–55 µm row within 10 % of a bracket edge |
Values are the manufacturer’s starting points, not a guarantee — characterize on your own tool. Series digitized from a published figure are approximate (±10 %).
Published dose is the datasheet’s own thickness bracket, quoted as printed — the full table and its citation are in the exposure section. A thickness the table does not cover shows nothing, and a thickness within 10 % of a bracket edge shows every bracket it could fall in.
KMPR 1050: read from figure 1 "Spin speed vs. Thickness for KMPR 1000 resists (21°C US & EU)", p.2 of the Kayaku Microchem/MicroChem "KMPR 1000 Chemically Amplified Negative Photoresist" datasheet (Ver. 4.2, UPenn nanoSOP mirror). Chart plots four curves (KMPR 1050/filled square, 1025/filled diamond, 1010/filled circle, 1005/open square), each with 4 markers at 1000/2000/3000/4000 rpm. The KMPR 1050 curve is the filled-square series and the topmost (thickest-film) curve at every rpm, consistent with its legend position (listed first) and Table 1's viscosity ordering (1050 = 13,000 cSt, the highest of the four, so it coats thickest at a given speed). A figure read, not a numeric table — no per-rpm table for this grade is published.
KMPR 1050 (23°C Japan & Asia): read from Figure 2 "Spin speed vs. Thickness for KMPR® 1000 resists (23°C Japan & Asia)", p.2 of the Kayaku Microchem/MicroChem "KMPR 1000 Chemically Amplified Negative Photoresist" datasheet (Ver. 4.2, UPenn nanoSOP mirror). The chart plots four curves (KMPR 1050/filled square, 1025/filled diamond, 1010/filled circle, 1005/open square), each with 4 markers at 1000/2000/3000/4000 rpm. KMPR 1050 is the filled-square series and the topmost (thickest-film) curve at every rpm, consistent with its legend position (listed first) and Table 1's viscosity ordering (1050 = 13,000 cSt, the highest of the four). A figure read — no numeric table of these values is published.
- Recommended program: dispense 1 ml of resist per inch (25 mm) of substrate diameter
- spin at 500 rpm for 5-10 s at 100 rpm/s acceleration, then spin at the target speed for 30 s at 300 rpm/s acceleration.
- The document publishes TWO spin curves for the same four resists at two different ambient conditions: Figure 1 (21°C, US & EU) and Figure 2 (23°C, Japan & Asia) — the curves are not identical (e.g. KMPR 1050 at 1000 rpm reads ~101 µm in Figure 1 vs. ~115 µm in Figure 2), a reminder that spin results are sensitive to coat-bowl ambient temperature/humidity and should be recharacterized on-tool.
- Both curves are plotted above: Figure 1 (21°C US & EU) as the primary curve and Figure 2 (23°C Japan & Asia) as a second series.
SOURCE: "Coat" / "Recommended Program", p.1, and Figures 1-2, p.2.
- Adhesion
- HMDS not required — "Adhesion promoters are typically not required." HMDS pretreatment (MCC Primer 80/20) is recommended "for applications that require electroplating" — and the document's own Plating process recipe lists HMDS as its first step.1
Soft bake
- Soft bake
- 100 °C · hotplate
- Notes
- Recommended bake temperature is 100°C (95-105°C also usable, per text) — this scalar temperature is explicit in the document.
SOURCE: Table 2 "Soft Bake Times" and "Soft Bake" section text, p.2
Exposure dose
KMPR 1050's dose is published against film thickness, not as a single number. Read the row for the film you coat and run a dose array around it.
- As published
- Dose climbs hard with thickness — 235–335 mJ/cm² at 5–11 µm, 1070–1465 mJ/cm² at 56–80 µm — and then the table stops at 80 µm, while this grade coats up to 101 µm at 1000 rpm.
- Post-exposure bake
- 100 °C
| Film thickness | Dose |
|---|---|
| 5–11 µm | 235–335 mJ/cm² |
| 12–20 µm | 355–485 mJ/cm² |
| 21–30 µm | 500–645 mJ/cm² |
| 31–55 µm | 665–1055 mJ/cm² |
| 56–80 µm | 1070–1465 mJ/cm² |
SOURCE: Microchem/MicroChem KMPR 1000 datasheet
Table 3 'Exposure Dose' of the Kayaku Microchem/MicroChem KMPR 1000 datasheet (Ver. 4.2). The published table stops at 80 µm — no dose is given above that, which is inside KMPR 1050's own coating range. Not attributed to a specific wavelength.
Development
- Developer
- 2.38% TMAH (0.26N) aqueous alkaline developer (primary); SU-8 Developer (solvent-based) is also usable as an alternative
- Dilution
- 2.38% TMAH (0.26N), used at this standard concentration (not diluted from a stock in the document)
- Time
- Not published — characterize on-tool
- Method
- immersion
- Rinse
- DI water, ~20 s spray rinse, then filtered air/N2 dry (TMAH path).
- Developer family
- TMAH or solvent
SOURCE: "Develop" and "Rinse and Dry" sections plus Table 5 (TMAH) and Table 6 (SU-8 developer), p.3
Hard bake, etch & strip
- Etch resistance
- Listed as a Feature: "Excellent dry etch resistance." Demonstrated in an application photo ("Etched Trenches", 10 µm features, 65 µm deep, credited to ULVAC) consistent with use as a DRIE (deep reactive ion etch) mask.2
- Stripper
- MicroChem Remover PG (NMP): heat bath to 80°C, immerse substrate 10-20 minutes (actual time depends on resist thickness and agitation, e.g. ultrasound).3
- Storage
- Store frozen, in tightly closed, upright containers, at 14°F (-10°C), away from light, heat, acids, and ignition sources.4
Not published for this resist: Hard bake, Descum — characterize on-tool.
SOURCE: "Plating" section note, p.3
Where it's used
Practical notes from the datasheet
KMPR 1050 is the thickest-coating grade in Kayaku Microchem/MicroChem's KMPR 1000 line and, unlike the solvent-developed SU-8 2000 family, is a chemically amplified epoxy resist designed to develop in aqueous TMAH — a meaningful process difference worth flagging for anyone assuming all thick epoxy negative resists behave like SU-8. Its published process tables (soft bake, exposure dose, TMAH develop time) only cover film thicknesses up to 80 µm, while KMPR 1050's own spin curve reaches roughly 101 µm at 1000 rpm; process engineers working at the thick end of this grade's range will need to extrapolate or characterize on-tool, since the datasheet simply does not publish numbers there. PEB time follows a thickness-threshold rule (2/3/4 minutes at 25/50 µm cutoffs) rather than a continuous table. A distinctive storage gotcha: KMPR 1000 resists must be stored frozen (14°F/-10°C) and require a full 24-hour room-temperature thaw before use — treating it like a room-temperature-stable resist will produce inconsistent films. The resist strips cleanly with Remover PG when only lightly cross-linked, but a fully electroformed/plated structure needs the stronger Remover PG → XP Remover K → XP Neutralizer K sequence to fully dissolve.
Grades in this family
Other grades in the KMPR 1000 series line differ mainly in coating thickness:
| Grade | Thickness |
|---|---|
| KMPR 1005 | 5.1–9.7 µm |
| KMPR 1050 (this page) | 34–115 µm |
Troubleshooting
Common failure modes for KMPR 1050, 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.
Why don't the KMPR 1050 process tables cover my film thickness?
KMPR 1050 coats to roughly 101 µm at 1000 rpm (115 µm on the 23°C curve), but the datasheet's soft-bake, exposure-dose and TMAH-develop tables stop at 80 µm. Above that there simply are no published numbers, so at the thick end of this grade you must extrapolate the trend and characterize on-tool rather than read a value off the sheet.
SOURCE: Kayaku Microchem KMPR 1000 datasheet (Ver. 4.2) — Tables 2, 3 and 5, p.2–3
What post-exposure bake does KMPR 1050 need?
PEB is at 100°C (95–105°C usable) on a hotplate, with time set by a thickness-threshold rule rather than a table: 2 min at ≤25 µm, 3 min above 25 µm and 4 min above 50 µm. KMPR 1050's 44–101 µm range straddles both thresholds, so choose by your actual film. A latent mask image should already be visible after about 1 min of PEB; if none appears, exposure or heat was insufficient.
SOURCE: Kayaku Microchem KMPR 1000 datasheet (Ver. 4.2) — Post Exposure Bake (PEB), p.3
Why is my KMPR 1050 film wrinkling or not fully drying on soft bake?
Soft bake at 100°C on a level hotplate — convection ovens are explicitly not recommended, since a skin can trap solvent. Published times are thickness-binned up to 80 µm (e.g. 15 min for 31–55 µm, 20 min for 56–80 µm). Use the datasheet's cool-down/re-heat 'wrinkle' check to confirm the film is fully dry before exposure.
SOURCE: Kayaku Microchem KMPR 1000 datasheet (Ver. 4.2) — Table 2 Soft Bake Times and Soft Bake section, p.2
Does KMPR 1050 need an adhesion promoter?
Adhesion promoters are typically not required. The exception is electroplating: HMDS pretreatment (MCC Primer 80/20) is recommended for plating applications, and the datasheet's own plating recipe lists HMDS as its first step. Note plated structures also change how the resist strips — a fully electroformed part needs the Remover PG → XP Remover K → XP Neutralizer K sequence.
SOURCE: Kayaku Microchem KMPR 1000 datasheet (Ver. 4.2) — Substrate Preparation and Plating, p.1 & p.3
Sources & disclaimer
- Kayaku Microchem (MicroChem) — KMPR 1050 datasheet (Ver. 4.2 (printed in the footer of every page: "Ver. 4.2")) · accessed 2026-07-10
- "Substrate Preparation", p.1, and "Plating", p.3.
- "Features" list and application photos, p.1.
- "Removal" / "Process Recommendation" / "Plasma Removal", p.3.
- "Storage", p.4.
- Lee et al.. Fabrication of thick electroforming micro mould using a KMPR negative tone photoresist. Journal of Micromechanics and Microengineering (2008). doi:10.1088/0960-1317/18/5/055032180 µm, 18:1 KMPR molds — strippable, unlike SU-8.
- Shin et al.. UV Lithography and Molding Fabrication of Ultrathick Micrometallic Structures Using a KMPR Photoresist. Journal of Microelectromechanical Systems (2010). doi:10.1109/JMEMS.2010.2045880KMPR molds for mm-wave traveling-wave-tube structures.
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 2026-07-26.