https://nanyte.com/photoresists/spr220-3 · last updated 2026-07-26
- Manufacturer
- Rohm and Haas Electronic Materials
- Tone
- Not photoimageable (underlayer)
- Chemistry
- DNQ-novolak
- Thickness
- 2.3–4.6 µm
- Exposure dose
- 310 mJ/cm² at 365 nm
- Developer
- MF-24A (0.24N MIF — metal-ion-free TMAH developer)
- Applications
- Etch mask · Electroplating / molding · MEMS structural
Cross-checked — two independent extractions agree on the spin curve and the single-value figures.
Spin coating
Data points
| Series | rpm | µm |
|---|---|---|
| SPR220-3.0 | 1500 | 4.6 |
| 2000 | 4.0 | |
| 2500 | 3.6 | |
| 3000 | 3.2 | |
| 3500 | 3.0 | |
| 4000 | 2.8 | |
| 4500 | 2.7 | |
| 5000 | 2.5 | |
| 5500 | 2.4 | |
| 6000 | 2.3 |
Values are the manufacturer’s starting points, not a guarantee — characterize on your own tool. Series digitized from a published figure are approximate (±10 %).
read from Figure 3 (p.2), 'Spin Speed Curves on 4"', of Rohm and Haas "MEGAPOSIT SPR220 Series Photoresists" datasheet (ME04N097, Rev. 2, Sept. 2004; UC Davis CNM2 mirror). The chart plots five curves (SPR220-7.0/circle, 4.5/square, 3.0/triangle, 1.5/diamond, 1.2/inverted-triangle), each with 10 markers from 1,500-6,000 rpm. SPR220-3.0 is the filled-triangle trace (3rd of 5), consistent with the series-naming convention where each grade's thickness near 3000 rpm approximates its nominal designation (this trace reads 3.23 µm at 3000 rpm ≈ 'SPR220-3.0'). Figure 3 is an embedded raster image, so this is a figure read; the 10 points fit a t∝1/√rpm curve to within ~1-3%.
- Figure 3 is measured on 4-inch substrates.
- Nominal film thickness may vary slightly with process, equipment, and ambient conditions, per the datasheet's own caveat under "Coat", p.2.
- Coat uniformity is separately reported for the SPR220-7.0 grade only (7.31 µm, standard deviation 0.036 µm across 33 points) — no uniformity figure is published for SPR220-3.0 specifically.
Soft bake
- Soft bake
- 115 °C · 1.5 min · hotplate
- Notes
- "The recommended softbake process for SPR220 for films up to 4.0 µm is 115°C for 90 seconds on a contact hotplate." SPR220-3.0's 3.0 µm nominal thickness falls within this “up to 4.0 µm” bin, so this is a direct (non-ranged) match, not a picked bin midpoint.
SOURCE: "Softbake" section, p.2, and Table 1 "Recommended Process Conditions" (1.1-4.0 µm column), p.1
Exposure dose
The manufacturer publishes 310 mJ/cm² 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 365 nm
- 310 mJ/cm²
- Dose at 405 nm
- Not published — characterize on-tool
- As published
- At this grade's nominal 3.0 µm coat, i-line sizing is 310 mJ/cm² and g-line 320 mJ/cm², both for 0.90 µm dense lines.
- Post-exposure bake
- 115 °C · 1.5 min
SOURCE: Table 2 "Photospeed and Linearity of Dense Lines/Spaces at Various Thicknesses", p.1
Development
- Developer
- MF-24A (0.24N MIF — metal-ion-free TMAH developer)
- Dilution
- 0.24N (MF-24A is the 0.24N-normality developer in Rohm and Haas's MF line; SPR220 is "optimized for 0.24N developers", with 0.26N (MF-26A) offered as an alternative for thicker films or high-throughput processes)
- Time
- 60 s
- Method
- puddle
- Rinse
- Not published — characterize on-tool
- Developer family
- TMAH or buffered alkaline
SOURCE: Table 6 "Recommended Develop Conditions" (3.0 µm FT column) and Table 1, p.1 and p.3
Hard bake, etch & strip
- Etch resistance
- "Excellent wet and dry etch adhesion" (Advantages, p.1).
- Stripper
- MICROPOSIT REMOVER 1165, two-bath process, each bath at 80°C (176°F): the first bath removes the bulk of the photoresist, the second removes residual traces.3
- Storage
- "Recommended storage for SPR220 is in an upright position in a dry area at 40-60°F (4-15°F). Keep away from oxidizers, acids, and bases.4
Not published for this resist: Hard bake, Descum — characterize on-tool.
Where it's used
Practical notes from the datasheet
SPR220-3.0 is the 3 µm-nominal member of the MEGAPOSIT SPR 220 line, a broadband resist usable at g-line (436 nm) or i-line (365 nm) that Rohm and Haas positions for thick-film MEMS, plating-mold, and DRIE-mask work rather than fine-pitch IC lithography. Unlike the thicker SPR220-7.0 grade, films at this 3.0 µm reference thickness stay under the datasheet's 4 µm threshold for the exposure-to-PEB rehydration hold, so processing is comparatively straightforward: softbake, PEB and (per Table 1) develop all run at essentially the textbook single-step conditions. The lineage of this resist family is worth noting for provenance purposes: Shipley Company originated the SPR line, was acquired into Rohm and Haas Electronic Materials (the entity printed on this 2004 datasheet), which was in turn acquired by Dow Chemical (2009), then spun into DuPont Electronics & Imaging, and the MEGAPOSIT/MICROPOSIT/MF brand family is now sold by Kayaku Advanced Materials — the same corporate family that owns MicroChem/KMPR and SU-8. Tone and base chemistry are not stated anywhere in this particular datasheet. Chemistry classified as dnq-novolak from the Dow MEGAPOSIT SPR220-3.0 MSDS composition table (cresol novolak resin + diazo photoactive compound).
Grades in this family
Other grades in the MEGAPOSIT SPR 220 series line differ mainly in coating thickness:
| Grade | Thickness | Exposure dose |
|---|---|---|
| Megaposit SPR 220-3.0 (this page) | 2.3–4.6 µm | 310 mJ/cm² @ 365 nm |
| Megaposit SPR 220-7.0 | 5.5–52 µm | — |
Sources & disclaimer
- Rohm and Haas Electronic Materials — Megaposit SPR 220-3.0 datasheet (ME04N097, Rev. 2, September 2004 (printed on p.1 and in the footer)) · accessed 2026-07-10
- https://asrc.gc.cuny.edu/wp-content/uploads/media/global-assets/Megaposit-SPR-220-3.0-Positive-Photoresist-MSDS.pdf — Dow MEGAPOSIT SPR220-3.0 MSDS states 'Cresol novolak resin 25.0-35.0%, Diazo Photoactive Compound 1.0-10.0%'; the basis for classifying SPR220-3.0 as dnq-novolak.
- "Substrate", p.2.
- "Post-Exposure Bake" section, p.3
- "Photoresist Removal", p.4.
- "Storage", p.4.
- Koukharenko et al.. A comparative study of different thick photoresists for MEMS applications. Journal of Materials Science: Materials in Electronics (2005). doi:10.1007/s10854-005-4977-2Benchmarks thick MEMS resists (SPR 220-7, SU-8, Ordyl P-50100 dry film, Diaplate 132) as electroplating molds; SPR 220-7 gives about 50 um molds for alkaline electroplating as an easier-to-strip alternative to SU-8.
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.