Samsung Display Uses Ultra-Thin Glass Substrates for Large TVs

Industries’ focus on yield of ultra-thin glass substrate with thickness of 0.4T (mm) that was used recently used by Samsung Display for LCD panels for large TVs has gotten bigger.

It is the first time out of all global manufacturers that this glass substrate was used for large panels and it was one of main causes that caused poor performance in first quarter. Most of industries believe that it was used by Samsung Display to reduce production cost and to upgrade performance of panels for curved TVs by one level. 

 

Samsung Display recently has started to use 0.4T glass substrates, which was used for small and mid-sized IT panels such as laptops, monitors and others, for large LCD panels for TVs. Many panel manufacturers such as LG Display, Innolux, AUO, BOE, CSOT and others are currently using glass substrates with thickness between 0.5 and 0.6T. Samsung Display is the first one to used 0.4T glass substrates for large panels for TVs. 
First attempt did not go too smoothly as it had caused problems with yield that eventually caused significant amount of operating loss for LCD business in first quarter. 

In the past, panel manufacturers had made 0.4T glass substrates by pouring hydrofluoric acid on top of glass substrates and going through separate slimming process. It was important to manufacture light and thin glass substrates that will increase portability of picture-phones, Smartphones, tablets, laptops and others.
If 0.4T is used for mother-glasses that are 8th generation and over, a problem where glass substrates starts to bend happens. Since it is too thin, a possibility of breakage due to bending increases. Rate of having poor back-end processes such as scribing for drawing a line to cut panels, assembly of modules and others also increases. Panel manufacturers have no choice but to face reduction of yield for short period of time. 

Industries believe that Samsung Display has chosen 0.4T glass substrates to increase performance of panels for curved TVs. Because penetration ratio increases as thickness of glass substrates decreases, clearer and brighter screens can be implemented even by using lesser electricity. Although competition in thickness and weight of TVs is less fierce than Smartphones and laptops, people are starting to prefer thinner and lighter TVs.
Because this glass substrate does not have to go through separate slimming process, it can increase competitive edge in production cost by reducing necessary cost for rear-end process.
Curved TVs are currently manufactured by physically bending flat panels unlike curved displays for Smartphones and others. To fix panels at bent stage, separate equipment are used. To optimize bent screens, separate pixels are laid out and technologies that can send source of light evenly to entire screen are needed.
0.4T LCD glass substrate was released by Corning last year when it released 8.5th Generation Eagle XG Slim. It said that performance was increased to optimize 0.4T LCD glass substrate for large curved displays. It decided to supply Eagle XG Slim to BOE’s newly-prepared 8.5th Generation LCD Line (B10) and also supplied Eagle XG Slim to Samsung Display. Japan’s NEG is currently planning to supply 0.4T glass substrates to LG Display and China’s CEC-Panda while Japan’s Asahi Glass is planning to supply them to China’s CSOT (CSO221T).