37‐3: Low Thermal Expansion and Fine‐Pitch Metal Masks Fabricated via Invar Fe‐Ni Alloy Electroforming for Large Fine‐Pitch OLED Displays

Abstract

Fine-pitch metal masks with approximately 10 μm thick and fine rectangular open areas (10 × 30 μm 2 ) were fabricated via invar Fe-Ni alloy electroforming (KEEPNEX TM ). The coefficient of thermal expansion (CTE) of the mask annealed at 600 °C was approximately 3 ppm/°C, i.e., four times lower than that of conventional electroformed Ni and Ni-Co alloys. The proposed alloy masks are expected to be used in vapor deposition processes to produce large fine-pitch OLED displays.

Influence of ultrasonic in low thermal expansion Fe-Ni electrodeposition process for micro-electroforming

“…Industrial applications such as integrated circuit (IC) packages, glass seals, organic light-emitting diode (OLED) shadow masks, composite material-forming molds, etc. are typical applications because of their low degree of thermal expansion, while applications such as read-write head magnetic memory, magnetic actuators, magnetic headers for hard disks, and in magnetic shielding are based on their soft magnetic properties [1] , [2] , [3] , [4] . Electroforming technology is an important process for extending the wide application of Fe-Ni alloys, such as the complex surface electroforming of Fe-Ni molds, the electroplating of Fe-Ni pins, the electroforming of Fe-Ni packages in electronic packaging, and the UV-LIGA electrodeposition of OLED Fe-Ni mask [5] .…”