Thick-Film Photoresist Series

Product Overview

Our Thick-Film Photoresist series is a positive-working photoresist based on the proven Novolac resin / DNQ (Diazonaphthoquinone) photosensitive system, engineered for film thickness ranging from 5μm to 20μm. Designed specifically for advanced packaging, LED deep trench, and MEMS fabrication, this product delivers exceptional step coverage over complex topographies, high aspect ratio profiles, and superior etch resistance. With ultra-low metal ion contamination (≤10ppb) and excellent adhesion to silicon, glass, oxide, and metal substrates, it is the ideal choice for demanding thick-film lithography applications in semiconductor manufacturing.

Key Features

· Thick Film Capability: Achieves uniform film thickness from 5μm to 20μm with excellent coating uniformity across large-area substrates, suitable for spin-coating and spray-coating processes.

· Excellent Step Coverage: Superior conformality over stepped topographies and deep trench structures, significantly reducing development defects and pinhole formation.

· High Aspect Ratio: Enables vertical sidewall profiles with aspect ratios up to 10:1, ideal for deep trench etching in LED and MEMS applications.

· Ultra-High Purity: Metal ion content controlled at ≤10ppb, preventing contamination during wafer fabrication and ensuring device reliability.

· Superior Etch Resistance: Excellent resistance to both wet and dry etching processes, serving as a robust masking layer with high selectivity against silicon, silicon dioxide, and metal layers.

· Wide Process Window: Generous depth of focus (DOF) and exposure latitude for high yield and process stability in production environments.

Typical Specifications

Parameter	Specification
Type	Positive Photoresist
Film Thickness	5 – 20 μm
Exposure Wavelength	365nm (I-line) / 405nm (G-line)
Resolution	3.0 – 5.0 μm
Metal Ion Content	≤10 ppb
Developer	2.38% TMAH (aq.) or IVF
Solvent	PGMEA
Soft Bake	90 – 110°C, 1 – 3 min
Post-Exposure Bake (PEB)	100 – 120°C, 1 – 3 min
Hard Bake	120 – 150°C, 2 – 5 min
Shelf Life	12 months (stored at 0–10°C, dark)

Applications

· Advanced Packaging: RDL (Redistribution Layer), Bumping, TSV (Through-Silicon Via), Fan-Out Wafer-Level Packaging (FOWLP), and 2.5D/3D heterogeneous integration

· LED Manufacturing: Deep trench etching for LED chips, current blocking layers, optical isolation structures, and surface texturing

· MEMS & Sensors: Micro-electro-mechanical system patterning, deep silicon etching, pressure sensors, accelerometers, gyroscopes, and bio-sensors

· Power Semiconductors: MOSFET, IGBT, SiC, GaN device fabrication including isolation structures and passivation layer patterning

· General Purpose: Thick-film masking, electroplating molds (LIGA process), surface passivation, and micro-structure fabrication

Available Grades

Grade	Film Thickness	Resolution	Best For
Standard Grade (YY-3520)	5 – 10 μm	5.0 μm	General advanced packaging, LED trench etching
High-Thickness Grade (YY-3520H)	10 – 20 μm	3.0 μm	Deep trench MEMS, high aspect ratio structures
High-Resolution Grade (YY-3520R)	5 – 8 μm	3.0 μm	Fine pitch RDL, advanced packaging, fine patterning
Anti-Reflective Grade (YY-3520AR)	5 – 15 μm	3.0 – 5.0 μm	High-reflectivity substrates, multi-layer stacks