Chances are you're reading this from a flat panel display, a technology that has changed the electronics industry, making it possible for devices to become truly mobile. Today, you’ll find flat panel screens in every car, home and even in your pocket! All of them are produced under vacuum conditions used to produce the thin film coatings that add the final layer to each display, regardless of technology.
The evolution of flat panel displays
The history of flat panel displays began in the mid-1980s with the first LCD (liquid crystal display) panels on laptops. Shortly thereafter, LCD computer monitors became available and replaced “CRT (cathode ray tube) televisions”, bulky and heavy computer monitors that you probably recognize from pictures and movies from the previous millennium. Since 2003, LCD displays have exceeded the sale of CRTs, and we've never looked back.
The technology started out small - literally! The first LCD displays in 1990 had a glass size known as Generation GEN1 (200-300 x 200-400 mm). Since then, dimensions grew consistently larger until they reached GEN11 (2340 x 3370 mm) in 2018. With the increase in production, the size of LCD TVs increased each year. As their sizes expanded, so did the technical demands on production machinery suppliers for glass handling, transporting and coating.
From around 2010, backlight technology in LCD TVs changed from a cold cathode fluorescent lamp to a dynamic LED backlight, bringing LCD technology to the forefront.
Approximately five years later, a new technology known as OLED (organic light emitting diode) was ready for mass production and established itself as an alternative to LCD. The advantages of OLED included a lower cost, its light weight, flexibility, better energy efficiency and better picture quality (especially for the color black).
Thin film coating for flat panel displays
Even the very first LCD screen was produced under vacuum conditions, and Leybold products have been used to manufacture them. Coating machine manufacturers count on us to provide full, tailor-made vacuum solutions developed for their process requirements. This often requires product adaptations simply because every manufacturer’s process is unique.
Some of the products we supply and the challenges they tackle include:
Backing pumps, or “fore vacuum”: On load lock chambers, vacuum pumps need the ability to work with extremely short cycles (i.e., 2-3 pumping cycles per minute, from 1000 to 1 mbar). For fast fore vacuum pumping or process chamber evacuation, we have a wide range of products, including intelligent POWER BOOST systems. These complete solutions are the perfect fit for any high-tech production process and take up less space than standard solutions.
High vacuum pumping: On process chambers, vacuum systems need the ability to achieve fast pump down times (down to 5x10-6 mbar) as well as continuous operation with gas load in pressure ranges of 10-2 to 10-3 mbar with argon, nitrogen and oxygen. For processes requiring an oil-free, dust and vibration-free process chamber, our TURBOVAC i, TURBOVAC MAG or COOLVAC pumps are the best choice.
For simpler process conditions, we recommend diffusion pumps, such as our DIJ and DIP.
Keep in mind that whichever high vacuum system you choose, it must have the ability to work continuously for long periods of time with high loads of inert and process gas mixtures.
Maintenance and spare parts: Keeping your processes running reliably is of vital importance in display production plants. Any unexpected downtimes can be very expensive and detrimental to the end-product. Therefore, we recommend investing in the most appropriate pump technologies, choosing high-quality parts and consumables and ensuring proper maintenance. Our Leybold technicians can help you support your processes by recommending the most appropriate maintenance schedules and advising you on spare parts and consumables.
Process control solutions: Stay on top of your vacuum system’s performance by having accurate vacuum measurement solutions in place. We have a portfolio of robust process gauges that cover all pressure ranges.
System integration: Make sure your vacuum pumps communicate with each other. Always choose equipment that fits together. We can provide various types of PLC and control solutions to match the precise needs of your coating processes.