https://nanyte.com/photoresists/lor-30b · last updated 2026-09-28
- Manufacturer
- MicroChem (MCC) — now Kayaku Advanced Materials
- Tone
- Not photoimageable (underlayer)
- Chemistry
- Ancillary (not photoimageable)
- Thickness
- 1.6–4.3 µm
- Exposure dose
- Not exposed — dissolves in developer
- Developer
- 0.24N TMAH or a metal-ion-bearing developer (no product named); 0.26N TMAH has some compatibility (selection guide, p.7).
- Applications
- Lift-off
Cross-checked — the spin curve (where published) and the single-value figures were read twice, independently, from the datasheet, with any disagreement settled against it.
- Substrate
- Underlayer
- Resist
- Exposed
Spin coating
Data points
| Series | rpm | µm |
|---|---|---|
| LOR 30B | 1000 | 4.3 |
| 1500 | 3.2 | |
| 2000 | 2.6 | |
| 2500 | 2.1 | |
| 3000 | 1.9 | |
| 3500 | 1.7 | |
| 4000 | 1.6 |
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 — the purple cross-marker trace legended LOR 30B on the 'Thickness vs. Spin Speed - LOR B Thick Series' chart, p.5, the highest of the five traces. Seven plotted markers at 500 rpm intervals; no numeric table accompanies the chart.
- The topmost trace on the B-series chart and the steepest at the slow end: 43,500 Å at 1000 rpm drops to 25,800 Å by 2000 rpm, then flattens toward 16,000 Å at 4000 rpm.
- Reaching the top of the range means spinning slowly, where thickness is most sensitive to speed and to dispense, so a target above about 4 µm is worth confirming on a test wafer rather than reading off the chart.
- Coating parameters are published for the product line rather than per grade: 5 ml dispensed dynamically over 3-5 s onto a 150 mm wafer at 300-500 rpm, 10,000 rpm/s acceleration to a 3,000 rpm terminal speed, 45 s spin, with EBR PG for edge-bead and whisker removal.
- Adhesion
- HMDS not required — "Primers, such as HMDS, are typically not required" when LOR/PMGI is used as recommended; the datasheet describes excellent adhesion across semiconductor substrates. To dehydrate the surface first, bake at 200 °C for 5 min. LOR/PMGI is virtually insoluble in typical photoresist solvents, so a properly baked underlayer does not intermix with the imaging resist above it.
Soft bake
- Soft bake
- 160–210 °C · hotplate
- Notes
- The prebake dries the film and fixes its dissolution and undercut rate, and no grade-specific temperature or time is published. The recommended prebake range for the product line is 160-210 °C, hotplate preferred, and some PMGI products bake as high as 280 °C. Prebake temperature has the greatest influence on undercut rate, with prebake time, developer choice, develop mode and especially develop time behind it. This is the thickest film in the B line, so bake time carries more weight here than on any other B grade — there is several times more solvent to drive out than in a sub-micron coat, and the published undercut-versus-bake curves (Figures 5a and 5b) were measured on LOR 10B, a film roughly a third this thickness.
SOURCE: Rev. D p.3: 'The recommended bake temperature range is 160°C –…
Rev. D p.3: 'The recommended bake temperature range is 160°C – 210°C'; 'Hot plates are the preferred tool for the prebake step.'
Exposure
LOR 30B is not photoimageable. It is not exposed at all — it is coated beneath an imaged top resist and undercut laterally during development. See the development step below.
Development
- Developer
- 0.24N TMAH or a metal-ion-bearing developer (no product named); 0.26N TMAH has some compatibility (selection guide, p.7).
- Developer family
- TMAH or buffered alkaline
Not published for this resist: Dilution, Time, Method, Rinse — characterize on-tool.
SOURCE: Product description, the LOR/PMGI process-flow section and the…
Product description, the LOR/PMGI process-flow section and the product selection guide, Kayaku "LOR and PMGI Resists" technical data sheet, Rev. D (August 2023)
Hard bake, etch & strip
- Stripper
- Remover PG — expect the long end of any strip time at this thickness. EBR PG removes edge beads and whiskers and is also an effective spin-bowl cleaner and a rework solvent for unbaked wafers.
- Storage
- Store upright in original sealed containers in a dry area between 10 and 24 °C (50-76 °F), away from ignition sources, light, heat, oxidants, acids and reducers. Do not use after the expiration date, 13 months from manufacture.
Not published for this resist: Hard bake, Descum, Etch resistance — characterize on-tool.
Where it's used
Practical notes from the datasheet
LOR 30B is the thickest sacrificial underlayer in the B series, a PMGI-based film spun beneath a conventional photoresist and never exposed. The reasoning for reaching this far up the range is geometric: a lift-off works when the metal on the substrate and the metal on top of the imaging resist never join, so the underlayer has to be comfortably thicker than the film being deposited, and below that it tears rather than releases. Going thicker than needed is not free — a fast-dissolving B-series film keeps undercutting for as long as the develop runs, and on a 4 µm coat that ledge can travel a long way, which is why the thick-film examples in this datasheet are drawn with features measured in tens of microns rather than fractions of one. Worth knowing before specifying it: the current revision also offers a C series reaching comparable thicknesses at a different dissolution rate, so thickness alone no longer picks the grade.
Grades in this family
Other grades in the LOR B series line differ mainly in coating thickness:
Troubleshooting
Common failure modes for LOR 30B, 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.
Fences are left along the pattern edges after lifting off a thick sputtered film over LOR 30B. Why?
Sputtering is close to isotropic, so it coats even the sidewalls of a deep undercut. MicroChemicals notes the remover then breaks through wherever it can, leaving fence-like ridges, and puts the practical limit for reproducible lift-off of sputtered films at a few hundred nm. Kayaku rates LOR/PMGI as compatible with sputter deposition but gives no thickness limit. Evaporation is directional and leaves undercut sidewalls uncoated, so a thick deposit on 30B lifts much more cleanly when evaporated.
SOURCE: MicroChemicals application note "Lift-off Processes with…
MicroChemicals application note "Lift-off Processes with Photoresist" — Sputtering or Evaporation?; "Fences" after Lift-off. Kayaku Advanced Materials, "LOR and PMGI Resists" technical data sheet, Rev. D (August 2023) — Deposition Process, p.4
Sidewalls on a thick LOR 30B coat come out sloped after immersion develop. What helps?
Spray development. The datasheet says straighter sidewalls with thick (>2 µm) LOR/PMGI layers come from spray, and 30B is above 2 µm at every speed up to about 2500 rpm (about 2.1 µm there, about 4.4 µm at 1000 rpm). Develop time is set by the LOR and imaging-resist thicknesses together, so a thick 30B stack needs a longer develop, and on a fast B film that longer develop also grows the undercut.
SOURCE: Kayaku Advanced Materials, "LOR and PMGI Resists" technical…
Kayaku Advanced Materials, "LOR and PMGI Resists" technical data sheet, Rev. D (August 2023) — Development Process, p.4; Undercut vs. Develop Time chart, p.4; Thickness vs. Spin Speed, LOR B Thick Series chart, p.5
Is LOR 30B thick enough to lift off a 3 µm metal film?
Only at the slow end. The datasheet wants the underlayer thicker than the deposit, typically by 33 %, which puts 3 µm of metal at about 4 µm of LOR. LOR 30B coats about 4.4 µm at 1000 rpm and drops to about 3.2 µm by 1500 rpm, so a 3 µm deposit means spinning close to 1000 rpm, where thickness is most sensitive to spin speed. The datasheet's stated deposition window for the LOR/PMGI line reaches beyond 3 µm.
SOURCE: Kayaku Advanced Materials, "LOR and PMGI Resists" technical…
Kayaku Advanced Materials, "LOR and PMGI Resists" technical data sheet, Rev. D (August 2023) — Features, p.1; Coating Process, p.2; Thickness vs. Spin Speed, LOR B Thick Series chart, p.5
Sources & disclaimer
- MicroChem (MCC) — now Kayaku Advanced Materials — LOR 30B datasheet (Rev. D, August 2023 (printed in the footer of every page)) · accessed 2026-09-10
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.