1. The coat process is the application of photoresist to the wafer’s surface. There are several methods used to coat the wafer (spin, spray and electrodeposition (ED)).
    The goal of the coat process is to distribute a uniform thickness of resist across the wafer's surface with a desired thickness.
    The resist must be thick enough and durable enough to withstand the next process steps.
    It must also be uniform in order to prevent problems during the expose process.
    Spin coating is the most common methods for coating a wafer.

      2. Spin Coater is a device for creating a thin film on a substrate. It is equipment that drops the solution to be coated on the substrate and rotates it to evenly coat the entire surface of the
          substrate.

3.  Spin Coating Requirements

  1. Uniform film thickness across wafer surfaces

  2. High-speed, precise control of spin speed and acceleration

    → The equipment of the Ewha ADL team ensures good performance.

  3. Edge Bead Removal (EBR) system for resist edge control

  4. Automated wafer handling (robotic arm, vacuum chucks)

    → Does not support Ewha ADL’s equipment.
     
  5. Exhaust and solvent vapor control systems

  6. Cleanroom compatibility

    → The Ewha team's equipment operates in a clean room environment
        and is installed in a hood with constant exhaust.