https://nanyte.com/photoresists/az-nlof-2035 · last updated 2026-07-26
- Manufacturer
- Merck
- Tone
- negative
- Chemistry
- Chemically amplified
- Thickness
- 3–6.1 µm
- Exposure dose
- 80 mJ/cm² at 365 nm
- Developer
- AZ 300MIF
- Applications
- Lift-off · Etch mask · High aspect ratio
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 |
|---|---|---|
| AZ nLOF 2035 | 500 | 6.1 |
| 1000 | 5.6 | |
| 1500 | 4.9 | |
| 2000 | 4.2 | |
| 2500 | 3.9 | |
| 3000 | 3.6 | |
| 3500 | 3.3 | |
| 4000 | 3.0 |
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 ("SPIN CURVES (150mm Silicon)"), p.1 of AZ nLOF 2000 Series datasheet — legend-labeled "nLOF 2035" (yellow/orange square marker), distinguishable from the nLOF 2070 (red diamond) and nLOF 2020 (blue diamond) traces by color and marker shape across the full 500-4000 rpm plotted range. Cross-checked against the grade-specific 3.5µm coat thickness stated in the EXAMPLE PROCESS table (p.4), which falls within this reading between the 2500 and 3000 rpm points.
- Multi-grade chart plots nLOF 2070 / nLOF 2035 / nLOF 2020 together (legend, distinct colors/markers, p.1); the nLOF 2035 trace sits clearly between the other two across the plotted range with a stated grade-specific 3.5µm anchor point (EXAMPLE PROCESS, p.4) that agrees with the read curve, giving reasonable confidence — but the reading is still a visual estimate from a plotted curve, not a printed numeric table, and no point is extrapolated past the 500-4000 rpm plotted range.
- No spin accel/dispense parameters or edge-bead removal procedure are published; AZ EBR Solvent/AZ EBR 70/30 are listed only as companion thinning/edge-bead products (COMPANION PRODUCTS, p.2) with no protocol given.
- No rehydration hold applies to this resist — the Typical Process table explicitly states "Rehydration Hold: None" (p.1); see the rehydration field.
- Adhesion
- HMDS recommended — Grade-specific EXAMPLE PROCESS (p.4): "Prime: HMDS 140°C/60s (vapor)".
- Rehydration
- None.
Soft bake
- Soft bake
- 110 °C (100–110 °C) · 60 s · hotplate
- Notes
- Grade-specific EXAMPLE PROCESS (3.5µm Film Thickness on Si, p.4): "Soft Bake: 110°C, 60s, direct contact hotplate", preceded by an HMDS vapor prime and followed by "Post Bake Delay: None".
SOURCE: EXAMPLE PROCESS (3.5µm Film Thickness on Si), p.4; SOFT BAKE, p.8 of AZ nLOF 2000 Series datasheet.
Exposure dose
The manufacturer publishes 80 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
- 80 mJ/cm²
- Dose at 405 nm
- Not published — characterize on-tool
- As published
- 80 mJ/cm² i-line is the nominal for a 3.5 µm film; the through-dose panel walks 72 to 96 mJ/cm², and profile shape moves with both dose and PEB temperature.
- Post-exposure bake
- 110 °C (100–115 °C) · 60 s
SOURCE: EXAMPLE PROCESS (3.5µm Film Thickness on Si), p.4 of AZ nLOF 2000 Series datasheet.
Development
- Developer
- AZ 300MIF
- Dilution
- used as supplied (ready-to-use MIF developer; industry-standard 0.26N/2.38% TMAH per DEVELOPING section)
- Time
- 2 min
- Method
- puddle
- Rinse
- Not published — characterize on-tool
- Developer family
- TMAH-based
SOURCE: EXAMPLE PROCESS (3.5µm Film Thickness on Si), p.4; DEVELOPING, p.8 of AZ nLOF 2000 Series datasheet.
Hard bake, etch & strip
- Etch resistance
- "May be processed with vertical sidewalls for RIE etching" (APPLICATION, p.1) — a qualitative capability claim; no etch rate or selectivity data is published.
- Stripper
- AZ 400T or AZ Remover 770 (STRIPPING, p.9): "AZ nLOF 2000 Series resists are compatible with industry standard solvent based removers."
Not published for this resist: Hard bake, Descum, Storage — characterize on-tool.
SOURCE: HARD BAKE, p.8; APPLICATION, p.1 of AZ nLOF 2000 Series datasheet.
Where it's used
Practical notes from the datasheet
AZ nLOF 2035 is the middle grade in Merck's AZ nLOF 2000 series, a chemically-amplified i-line negative resist purpose-built to give an undercut lift-off sidewall from a single standard expose/PEB/develop flow, without the extra image-reversal bake/flood-expose steps older negative processes required. The PEB is not optional here — the datasheet states it is "required for proper imaging" and the resist's CD is directly sensitive to PEB temperature (documented at ~0.03-0.04 µm/°C for this exact 3.5µm film thickness); getting PEB temperature and time right matters more for this chemistry than for a standard DNQ positive resist. No rehydration hold is needed (explicitly "None" per the Typical Process table), but delays between soft bake and exposure should be minimized. It is not recommended for copper substrates. One internal inconsistency in the source document is worth flagging: a Linearity/Exposure-Latitude chart on p.6 is captioned "AZ nLOF 2020 @ FT=3.5µm" even though 3.5µm and a 120s develop otherwise match the nLOF 2035 example elsewhere in the same document — this recipe does not use that chart's data, since the document itself names it as the 2020 grade.
Grades in this family
Other grades in the AZ nLOF 2000 series line differ mainly in coating thickness:
| Grade | Thickness | Exposure dose |
|---|---|---|
| AZ nLOF 2020 | 1.6–4.6 µm | 66 mJ/cm² @ 365 nm |
| AZ nLOF 2035 (this page) | 3–6.1 µm | 80 mJ/cm² @ 365 nm |
| AZ nLOF 2070 | 5.3–11.8 µm | — |
Troubleshooting
Common failure modes for AZ nLOF 2035, 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.
How do I get an undercut lift-off profile with AZ nLOF 2035?
AZ nLOF 2035 is a chemically amplified negative resist purpose-built to replace image-reversal processing — the undercut lift-off sidewall comes directly from a standard expose/PEB/develop flow. The PEB is required for imaging. The 3.5 µm reference process runs 80 mJ/cm² i-line, PEB 110°C/60 s, then a 120 s AZ 300MIF puddle, and the film is thermally stable to >200°C.
SOURCE: AZ nLOF 2000 Series datasheet — EXAMPLE PROCESS (3.5µm on Si), p.4
How sensitive is AZ nLOF 2035's linewidth to post-exposure-bake temperature?
Very — the datasheet's grade-specific PEB study for this 3.5 µm film tested 105/110/115°C at 60 s and measured Top/Bottom CD of 1.734/0.726 µm, 1.992/1.439 µm and 2.062/1.687 µm, i.e. roughly 0.03–0.04 µm/°C. A few degrees of drift visibly changes both linewidth and undercut, so hold the PEB temperature tightly; the datasheet's general rule is a 100–115°C PEB window.
SOURCE: AZ nLOF 2000 Series datasheet — EXAMPLE PEB SENSITIVITY (3.5µm on Si), p.5, and POST EXPOSE BAKE, p.8
What exposure dose does AZ nLOF 2035 need?
The 3.5 µm reference process uses 80 mJ/cm² nominal at i-line (365 nm); the adjacent through-dose panel sweeps 72/80/88/96 mJ/cm² around it. Profiles can be tuned by trading exposure dose against PEB temperature. Exposure must be at 365 nm, and no h-line (405 nm) dose is published.
SOURCE: AZ nLOF 2000 Series datasheet — EXAMPLE PROCESS (3.5µm on Si), p.4
Why does AZ nLOF 2035 develop longer than the thinner nLOF grades?
The 3.5 µm reference process uses a single 120 s AZ 300MIF puddle — twice the 60 s used for the 2.0 µm nLOF 2020 example — because a thicker film needs more time to clear. AZ 300MIF is a ready-to-use 0.26N/2.38% TMAH developer. No rehydration hold is needed; just minimize the soft-bake-to-exposure delay.
SOURCE: AZ nLOF 2000 Series datasheet — EXAMPLE PROCESS (3.5µm on Si), p.4, and DEVELOPING, p.8
Sources & disclaimer
- Merck — AZ nLOF 2035 datasheet (Rev. (03/21)) · accessed 2026-07-10
- Kim et al.. Electrical access to critical coupling of circularly polarized waves in graphene chiral metamaterials. Science Advances (2017). doi:10.1126/sciadv.1701377AZ nLOF 2035 was used as the negative-tone lift-off stencil for a 100 nm gold layer over a 10 nm chromium adhesion layer, defining the double-Z chiral metamaterial pattern of a graphene-gated device.
- Son et al.. Thermal Recovery of Damaged Hydrophobic Coatings in EWOD Devices Using an Integrated Mesh-Patterned Heater. Micromachines (2026). doi:10.3390/mi17050631AZ-nLOF 2035 was spin-coated and patterned on the backside glass of an electrowetting device, then used to lift off a 100 nm nichrome film into a mesh-patterned integrated heater.
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.