Flat panel display (FPD) manufacturing is synonymous with ‘generational’ shifts when panel size has increased year by year. Vacuum processing is used in all flat panel displays (as it was for the production of CRT TVs). This includes Plasma Display Panels (PDP), Liquid Crystal Displays (LCDs) and Organic Light Emitting Diode (OLED) displays.
The most ubiquitous flat panel technology in use today is Active Matrix, Thin Film Transistor, LCD (AM-TFT-LCD) which uses similar processes to fabricate the transistor switches, capacitors and conductors as are used for microchip semiconductors, but on glass substrates rather than silicon wafers. These vacuum-based processes include:
- Physical Vapour Deposition (PVD) – sputter coating for metal and transparent conducting oxide (TCO) electrodes
- Plasma Enhanced Chemical Vapour Deposition (PECVD) – growth of the amorphous silicon and SiN thin film transistor structures
- Plasma dry etching – etch back of the fine structure using photolithography techniques.
Several panels are fabricated on one substrate. After the assembled substrates are separated into individual panels, the empty cells are filled with liquid crystal material by vacuum injection and then sealed.
Increasing the number of panels produced on a single substrate increases the yield of the very complex fabrication processes and the panel cost can be reduced. Also, user demand has steadily increased the average panel size. These two drivers have meant that the substrate size has steadily increased - requiring the continual design and construction of new generations of process equipment including vacuum pumps and their abatement systems.
Edwards has an established track record of experience and expertise in providing cost-effective solutions for each generation. Large process pump-sets and exhaust management systems for reliable and safe handling of silicon deposition and chamber cleaning gases (silane and fluorine based) are being continually developed. Large load-lock pump-sets for efficient, rapid pump-down cycling increase the overall throughput by reducing the time taken to get batches of substrates into and out of the process chambers.
Edwards offers a comprehensive range of modular vacuum pump and exhaust management systems designed to improve FPD processes, minimizing downtime and extending product life with lower costs of ownership. . As well as process-specific product selection, system design and manufacture, Edwards provides commissioning and 24/7 on-site service support.
Drypumping Abatement systems STP Turbomolecular pumps Measurement & control