Have You Ever Used The Ultrasonic Spraying in The Photoresist Industry?

The core application of ultrasonic atomization spraying in the photoresist industry is the coating of photoresist with high precision, high uniformity, and high step coverage. It is particularly good at solving the coating problems of 3D microstructures, high aspect ratios, and large/irregular substrates that are difficult to handle by traditional spin coating, while significantly improving material utilization and yield.

1. Semiconductor Wafer Coating (Mainstream Applications)

Planar Wafer Coating: Used for 12-inch and larger wafers, achieving ultra-thin, uniform photoresist layers (thickness 50–500 nm), with thickness error controllable within ±0.3–0.4 μm and uniformity >95%, significantly improving exposure accuracy and chip yield.

Complex Structure Wafer Coating: Targeting deep trenches, TSVs, and high aspect ratio structures, solving spin-coating issues such as edge buildup, bottom missing resist, and shadowing effects, achieving uniform coverage on sidewalls and the bottom, ensuring etching/ion implantation accuracy.

2. MEMS and Microstructure Device Coating

Coating of 3D complex morphological surfaces such as MEMS chips, microfluidic chips, sensors, and micromirrors, providing excellent step coverage, eliminating dead corners and bubbles, and improving device reliability.

Specialty Substrates and Flexible Electronic Coating

Coating of non-silicon substrates such as glass, ceramics, metals, and flexible substrates (e.g., PI, PET), suitable for irregularly shaped/large-sized/fragile parts, avoiding the fragmentation risk caused by high-speed centrifugation during spin coating.

Coating of photoresist/functional layers on flexible/curved substrates such as flexible OLEDs and perovskite solar cells.

R&D and Small-Batch Prototyping

Laboratory R&D, new material verification, and small-batch prototyping: rapid changeover, precise film thickness control, and low material consumption, suitable for photoresist formulation development and process iteration.

Hybrid Process (Spin Coating + Ultrasonic Spraying)

First, ultrasonic spraying forms a uniform base film, then high-speed spin coating evens the adhesive, balancing uniformity, step coverage, and production efficiency, suitable for advanced processes.

Typical Process Parameters (Reference)

●Atomization Frequency: 20–120 kHz (100 kHz is commonly used)

●Atomization Particle Size: 0.5–50 μm (submicron level)

●Film Thickness Range: 50 nm–5 μm (50–500 nm is commonly used for precision coating)

●Thickness Uniformity: ±0.3–0.5 μm (12-inch wafer)

●Material Utilization: >90%