AZ 12XT process recipe

AZ 12XT is a chemically amplified positive-tone thick photoresist for single-coat films from about 3 to over 20 µm, built for fast, high-throughput TSV, RDL, and RIE etch-mask lithography with a required post-exposure bake.

https://nanyte.com/photoresists/az-12xt · last updated 2026-07-10

At a glance

Manufacturer: Merck
Tone: positive
Chemistry: Chemically amplified
Thickness: 3–20 µm
Developer: AZ 300MIF
Applications: Etch mask · Electroplating / molding · High aspect ratio

Etch maskSuitable for

Cross-checked — two independent extractions agree.

Coat3–20 µm Softbake110 °C · 2 min · hotplate

—01 / Coating

Spin coating

AZ 12XT is spin-coated to 3–20 µm. The curve below is redrawn from the manufacturer's published data — read your target thickness off the vertical axis and take the matching spin speed as a starting point.

AZ 12XT-20PL-15
AZ 12XT-20PL-10
AZ 12XT-20PL-05

Data points

AZ 12XT — film thickness (µm) by spin speed (rpm)
Series	rpm	µm
AZ 12XT-20PL-15	1000	23
	1500	18
	2000	15
	2500	13
	3000	12
	3500	11
	4000	10
AZ 12XT-20PL-10	1000	14
	1500	11
	2000	9.5
	2500	8.3
	3000	7.5
	3500	7.0
	4000	6.7
AZ 12XT-20PL-05	1000	6.2
	1500	4.8
	2000	4.2
	2500	3.8
	3000	3.5
	3500	3.2
	4000	3.0

Values are the manufacturer's starting points, not a guarantee; verify on your own tool. Characterize on-tool. Series digitized from a published figure were independently cross-checked by a second blind read; treat those values as approximate (±10 %).

AZ 12XT-20PL-15: read from figure, p.1 of AZ 12XT-20PL Series Technical Datasheet (Merck, Rev. 03/21), 'SPIN CURVES (150MM SILICON)'. Three-grade chart; traces identified by the chart's own legend (red triangle = AZ 12XT-20PL-15, blue circle = AZ 12XT-20PL-10, green diamond = AZ 12XT-20PL-05), not by color alone.

AZ 12XT-20PL-10: read from figure, p.1 of AZ 12XT-20PL Series Technical Datasheet (Merck, Rev. 03/21), 'SPIN CURVES (150MM SILICON)'. Three-grade chart; traces identified by the chart's own legend (red triangle = AZ 12XT-20PL-15, blue circle = AZ 12XT-20PL-10, green diamond = AZ 12XT-20PL-05), not by color alone.

AZ 12XT-20PL-05: read from figure, p.1 of AZ 12XT-20PL Series Technical Datasheet (Merck, Rev. 03/21), 'SPIN CURVES (150MM SILICON)'. Three-grade chart; traces identified by the chart's own legend (red triangle = AZ 12XT-20PL-15, blue circle = AZ 12XT-20PL-10, green diamond = AZ 12XT-20PL-05), not by color alone.

3 series redrawn from the manufacturer's published data — hover to read values between points, click to pin.

QC flag: the chart's own y-axis is printed as 'Film Thickness (nm)' (p.1), which is almost certainly a labeling typo in the vendor's document - the plotted values (2-24) and the product's stated 3.0->20µm single-coat range (same page) only make sense as micrometres, and the grade names (-05/-10/-15) line up with the 5/10/15 µm worked-example film thicknesses used later in the same datasheet (pp.3-5). I read and recorded the values as µm; a human reviewer should still see the original 'nm' axis label and confirm this reading against the PDF. No numeric spin-curve table is printed elsewhere, so this figure read is the only source for spinCurves.

Adhesion: HMDS recommended — 'Oxide forming substrates (Si, etc.) should be HMDS primed prior to coating AZ 12XT.' (p.9, Substrate Preparation). Every worked process example in the document starts with an explicit 'Prime: HMDS 140°C/60s (vapor)' step (pp.3-5,8).
Rehydration: None - 'Rehydration Hold: None' is stated explicitly in the Typical Process summary (p.1).

—02 / Bake

Soft bake

Soft bake: 110 °C · 2 min · hotplate
Notes: Typical Process states a single value: '110ºC/120s' (p.1). Process Considerations separately gives a broader acceptable range, '95°-110°C' (p.9), with no time. Every worked example specifies 'direct contact hotplate' and scales time with thickness: 110°C/120s @5µm (p.3), 110°C/180s @10µm (pp.4,8), 110°C/240s @15µm (p.5). A footnoted caution applies to thicker coats: 'Thicker films may require a ramped soft bake process to avoid bubble formation due to rapid outgassing of solvents' (pp.4-5). A separate caution applies to thinner coats: films under 6µm may pick up airborne amine contamination if softbake-to-expose delay is excessive and should be exposed/developed within 30-45 minutes of softbake (p.3 footnote) - this is an amine-poisoning risk specific to CAR chemistry, not a rehydration/moisture issue, and is recorded here rather than in the rehydration field.

SOURCE: p.1 (Typical Process, used for temp_c/time_s above); p.9 (range); pp.3-5,8 (worked examples)

—03 / Exposure

Exposure dose

The manufacturer does not publish a clearing dose for AZ 12XT. Determine it with a dose array on your own tool.

As published: 'AZ 12XT requires exposure energy at the 365nm wavelength.' (p.9, Exposure); Typical Process: 'Expose: 365nm sensitive' (p.1).
Post-exposure bake: 90 °C · 60 s

—04 / Development

Development

Developer: AZ 300MIF
Dilution: 0.26N (2.38%) TMAH, ready-to-use
Method: puddle
Developer family: TMAH-based

SOURCE: p.1, p.9 (developer); pp.3-5,7,8 (worked-example times)

—05 / Post-processing

Hard bake, etch & strip

Etch resistance: Described only qualitatively: 'Excellent for Through Silicon Via (TSV), plating, and RIE etch applications' (p.1); hard bake (100-115°C) is said to improve 'pattern stability in dry etch processes' (p.9). No etch rate or selectivity number is given.
Stripper: AZ Kwik Strip, AZ 300T, or AZ 400T (solvent-based removers, all three explicitly recommended, p.9)

SOURCE: p.9 (Hard Bake)

—06 / Applications

Where it's used

Etch maskElectroplating / moldingHigh aspect ratio

AZ 12XT is a chemically amplified positive-tone counterpart to the vendor's negative nXT line, aimed at the same TSV/RDL plating-mask and RIE etch-mask space but developing and exposing faster for higher tool throughput. Unlike the thick DNQ resists this recipe library also covers, no rehydration hold is needed - but the tradeoff is a PEB that is explicitly required (not optional) for the latent image to develop at all, and a real amine-sensitivity window: coats thinner than 6 µm must be exposed and developed within 30-45 minutes of softbake or airborne base contamination can degrade the pattern, a classic chemically-amplified-resist failure mode distinct from DNQ rehydration. Exposure dose and develop time both scale strongly with film thickness across the worked examples (100-250 mJ/cm2; 2x30s to 2x60s puddles), so there is no single number to quote - see the exposureDose and develop _note fields for the full table. HMDS priming is required on Si. Hard bake is optional and helps adhesion/etch stability rather than being required for imaging.

—07 / Sources

Sources & disclaimer

Merck — AZ 12XT datasheet (Rev. (03/21)) · accessed 2026-07-10

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 2026-07-10.

Cite this recipe

NANYTE. "AZ 12XT process recipe." NANYTE Photoresist Library. https://nanyte.com/photoresists/az-12xt. Accessed 2026-07-10.

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