https://nanyte.com/photoresists/spr220-3 · last updated 2026-09-28
- Manufacturer
- Rohm and Haas Electronic Materials
- 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). 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.
- Adhesion
- HMDS recommended — "A hexamethyldisilizane (HMDS)-based MICROPOSIT primer is recommended to promote adhesion with substrates that require such treatment. Vacuum vapor priming at 120°C for 30 seconds with concentrated HMDS is recommended."1
- Rehydration
- Not applicable at SPR220-3.0's nominal 3.0 µm reference thickness. The datasheet's exposure-to-PEB moisture-diffusion hold requirement applies only to "films above 4 µm" (minimum 35-minute hold) and films ">12 µm" (minimum 120-minute hold) — both thicker than this grade's 3.0 µm nominal coat, so no hold time is called for at the reference process point. (See the SPR220-7.0 entry, where this hold is required.)2
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, matching it directly rather than sitting between bin edges. Table 1 independently confirms the same value for the 1.1-4.0 µm thickness class: "115°C/90 sec. Contact Hotplate."
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. The thick-film guidance for films over 12 µm is a different regime and does not apply here.
- 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). Figure 8 (p.4) reports 100:1 etch selectivity in a Bosch DRIE process, demonstrated patterning 2.5-10 µm features to 200 µm deep and 5-20 µm features to 100 µm deep (these etch-depth examples are shown at the SPR220 series level, not attributed to a specific grade). A 1:5 HF wet-etch example (2 µm feature) is also shown on 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. Keep container sealed when not in use." (Quoted verbatim, including an apparent unit inconsistency in the source: 40-60°F does not correspond to 4-15°F — the parenthetical is likely a typo for °C in the original document; it is quoted as printed rather than corrected.)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. This resist family traces from Shipley Company, which originated the SPR line, through Rohm and Haas Electronic Materials (the entity printed on this 2004 datasheet), then Dow Chemical (2009), then DuPont Electronics & Imaging, to today's 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. The dnq-novolak chemistry entry draws on 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 | — |
Troubleshooting
Common failure modes for Megaposit SPR 220-3.0, 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.
I spun SPR220-3.0 slowly to get a thicker film. Do the thin-film bake rules still apply?
Not once the film passes 4 µm, which SPR220-3.0 does at the slow end of its Figure 3 curve. Above 4 µm the datasheet switches to a 30 s step-down ramp onto the 115 °C hotplate with at least a 90 s hold, and asks for a minimum 35-minute wait between exposure and PEB so water can diffuse back into the film and complete the photoreaction. MicroChemicals' trouble shooter adds that a bake soon after exposure can turn the exposure's nitrogen into bubbles. At or below 4 µm, the straight 115 °C / 90 s softbake and no hold apply.
SOURCE: Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097…
Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097, Rev. 2, Sept. 2004) — Figure 3 and Softbake, p.2; Post-Exposure Bake, p.3; MicroChemicals GmbH 'Photolithography Trouble Shooter' — Bubbles in Resist Film after Thermal Processes, p.15
SPR220-3.0 won't clear at 310 mJ/cm² on my contact aligner. Is the datasheet dose wrong?
It is right for its own conditions. The 310 mJ/cm² i-line figure for a 3.0 µm film is a photospeed for dense lines and spaces with 0.90 µm linearity, on the ASML PAS 5500/200 i-line stepper (0.48 NA) that Table 1 lists and developed per Table 6; the sheet gives 320 mJ/cm² at g-line alongside it. Its Figure 2 shows 1.0 µm and 0.9 µm lines at those doses. A broadband aligner delivers a different spectrum and intensity, so treat 310 mJ/cm² as the order of magnitude and run a dose series on your aligner at your actual thickness.
SOURCE: Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097…
Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097, Rev. 2, Sept. 2004) — Table 1 (expose tool) and Table 2 (3.0 µm rows), p.1; Figure 2 'Resolution at 3.0 µm Film Thickness', p.2
Which developer conditions apply to a 3.0 µm SPR220-3.0 film? My process sheet was written for SPR220-7.0.
Use the 3.0 µm column of Table 6, not the 7.0 µm one: MF-24A or MF-26A for 60 s as a single spray puddle, or the metal-ion-bearing M452 for 3 minutes by immersion. The 60/60 s double puddle belongs to the thicker films, and M453 has no 3.0 µm condition at all — the table lists it only from 5.0 µm up. SPR220 is optimised for 0.24N developers, with 0.26N offered for thicker films or throughput. Table 1 gives MF-24A at 21 °C as the series default.
SOURCE: Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097…
Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097, Rev. 2, Sept. 2004) — Develop section and Table 6 'Recommended Develop Conditions', p.3; Table 1, p.1
SPR220-3.0 lifts at the edges in a wet etch, or leaves scum in the opened areas. Is it the priming?
It can be. The datasheet recommends vacuum vapour priming with concentrated HMDS at 120 °C for 30 s on substrates that need it. MicroChemicals' trouble shooter explains how priming done the wrong way causes its own trouble: HMDS spun on as a liquid, or HMDS vapour in the coater that also spins the resist, releases ammonia in the softbake that modifies the resin at the substrate and can leave a layer that will not develop through. Prime from vapour onto a heated wafer and keep HMDS out of the resist coater. SPR220 lists silicon, aluminium oxide, gold, copper and NiFe as compatible substrates.
SOURCE: Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097…
Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097, Rev. 2, Sept. 2004) — Substrate, p.2; MicroChemicals GmbH 'Photolithography Trouble Shooter' — HMDS Applied Correctly? p.7–8 and Inferior Resist Adhesion: Wrong HMDS Application, p.11
The SPR220-3.0 storage line reads '40–60°F (4–15°F)'. Which is right?
40–60 °F is about 4–15 °C, so the parenthetical is a unit misprint: it means Celsius. Store SPR220-3.0 upright in a dry area at that temperature, sealed when not in use, and away from oxidisers, acids and bases. For removal, the datasheet recommends MICROPOSIT REMOVER 1165 in two baths, both at 80 °C: the first takes off the bulk, the second the residual traces.
SOURCE: Rohm and Haas MEGAPOSIT SPR220 Series datasheet (ME04N097, Rev. 2, Sept. 2004) — Storage and Photoresist Removal, p.4
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 2026-09-28.