Positive Photoresist Spraying

Application of ultrasonic spraying technology to spray positive photoresist on 2-inch square ceramic wafers.

In the field of microelectronics manufacturing and precision machining, the application of photoresist is crucial. As a key material in the photolithography process, it is used to protect areas where etching or deposition of materials is not required. Ultrasonic spraying technology shows significant advantages in the application of photoresist due to its high precision and uniformity. This article will introduce in detail how to use an ultrasonic spray machine to evenly spray positive photoresist with a viscosity of 50cps on a 2-inch square ceramic wafer.

1. Introduction to positive photoresist
Photoresist is a photosensitive material used in the photolithography process, which is divided into positive and negative photoresists. Positive photoresists will be dissolved after exposure, exposing the underlying material, and are suitable for positive pattern transfer. The viscosity of photoresist is an important parameter that affects its application performance. The viscosity of 50cps means that the photoresist has a certain fluidity and is suitable for spraying fine patterns.

2. Principle of Ultrasonic Spraying Technology
Ultrasonic spraying technology uses ultrasonic high-frequency vibration to atomize liquid photoresist into tiny particles, and sprays these microparticles evenly onto the surface of the substrate through precisely controlled airflow. This technology has the following characteristics:

• High uniformity: Ultrasonic vibration ensures the uniformity of liquid atomization, so that the thickness of the photoresist layer sprayed on the substrate is uniform.
• High precision: Accurate coating thickness control can be achieved by adjusting the ultrasonic frequency and spraying parameters.
• Low material waste: Due to the precision of the spraying process, material waste is reduced.

3. Spraying process

• Preparation: Make sure the surface of the 2-inch square ceramic sheet is clean, dry, and free of dust and oil. Adjust the parameters of the ultrasonic spray machine, including ultrasonic frequency, distance between the nozzle and the substrate, airflow speed, etc., to adapt to the viscosity of 50cps photoresist.
• Adjust the spray machine: Adjust the nozzle size and spray mode of the spray machine according to the viscosity of the photoresist and the size of the ceramic sheet. For 2-inch square ceramic sheets, select a suitable nozzle and spray path.
• Spraying operation:
  – Pour the photoresist positive photoresist into the material tank of the spray machine.
  – Start the ultrasonic spray machine and adjust it to the predetermined spraying parameters.
  – Fix the ceramic sheet on the stage of the spray machine.
  – Start spraying, making sure that the nozzle moves at a uniform speed on the surface of the ceramic sheet to obtain a uniform coating.
• Inspection and post-processing: After spraying, check the uniformity and thickness of the photoresist layer. If necessary, perform post-processing, such as drying steps, to solidify the photoresist layer.

Summary: Using an ultrasonic spray machine to evenly spray a 50cps photoresist positive photoresist on a 2-inch square ceramic sheet is an efficient and precise processing method. By accurately controlling the spraying parameters, the quality and uniformity of the photoresist layer can be ensured, providing a good foundation for subsequent photolithography processes. With the continuous development of the microelectronics industry, the application of ultrasonic spraying technology in the field of precision manufacturing will be more extensive.

About Cheersonic

Cheersonic is the leading developer and manufacturer of ultrasonic coating systems for applying precise, thin film coatings to protect, strengthen or smooth surfaces on parts and components for the microelectronics/electronics, alternative energy, medical and industrial markets, including specialized glass applications in construction and automotive.

Our coating solutions are environmentally-friendly, efficient and highly reliable, and enable dramatic reductions in overspray, savings in raw material, water and energy usage and provide improved process repeatability, transfer efficiency, high uniformity and reduced emissions.

Chinese Website: Cheersonic Provides Professional Coating Solutions