Fine Metal Masks are ultra-thin metal masks used in the OLED evaporation process.Their main functions include:
Controlling OLED material deposition
Ensuring precise RGB pixel alignment
Improving display resolution
Maintaining panel consistency
As display technology advances toward high-resolution and large-size panels, the manufacturing accuracy of FMM masks becomes increasingly important.

Materials Used for FMM Masks
FMM masks are typically made from high stability metal materials such as:
Invar alloy
Stainless steel
Specialized low expansion alloys

These materials provide:
Low thermal expansionHigh structural stability
Excellent micro-processing performance

To achieve micron-level precision structures, FMM manufacturing typically uses photolithography combined with chemical etching.

FMM Chemical Etching Manufacturing Process
The typical process includes:
Material preparation
Selecting high precision metal sheets.
Photolithography
Transferring fine patterns onto the metal surface.
Chemical etching
Etching the unprotected areas to create micro apertures.
Cleaning and resist removal
Removing photoresist and cleaning the surface.
Precision inspection
Ensuring aperture accuracy and pattern consistency.