Samsung Display to produce LTPS-TFT Micro LED displays

Samsung Display is considering manufacturing thin film transistors (TFTs) that will be used in Micro LED TVs produced by Samsung Electronics.

According to sources, the manufacturer has assembled a Korean team to oversee the project. The team was formed in April and the project is called "Project M." M stands for micro LED.

Samsung Display does this in accordance with the requirements of Samsung Electronics. The South Korean tech giant, whose TV business is called the Visual Display business, made a request to Samsung Display earlier this year to produce low-temperature polysilicon (LTPS) TFTs for Micro LEDs.

TFT acts as a switch, turning pixels on the display on and off. Samsung's previous Micro LED TVs were over 100 inches in size and used printed circuit boards (PCBs).

However, the technology giant is planning to apply LTPS-TFT to Micro LED TVs.

This is because smaller TV models mean they will use smaller LEDs, which are packed more tightly. Using LTPS TFTs will allow microcircuit designs that can individually control these smaller LEDs. This is difficult to do with circuits on traditional PCBs.

Samsung Display will produce LTPS TFTs at its Cheonan factory’s A1 production line (4th generation, 730930mm). A1 previously produced LTPS TFT rigid OLED panels. But Samsung Display currently produces rigid OLED panels on its A2 production line (Gen615001850mm), which has higher production efficiency. Sources said that as of the first half of 2021, A1's operating rate was only in single digits.

Using A1’s Gen 4.5 substrate will produce 12 to 16 9.7-inch Micro LED modules. Samsung currently uses these 9.7-inch micro LE D modules are used to assemble micro LED TVs. A1's current production capacity is 55,000 substrates per month.

Sources said that for the production process of Micro LED LTPS TFT, a total of 24 masks are expected to be required. This is because it will have a lot of transistors and circuits. Typically, for 6th generation OLED substrates, 11 to 12 masks are used. More masks mean a more complex production process.

Sources said Samsung Electronics' request to Samsung Display came at the same time as it asked its display manufacturing subsidiary to extend production of liquid crystal display (LCD) panels.

Initially, Samsung Electronics made a request to Taiwan AUO to manufacture the micro LEDs required for LTPS TFT is. However, Samsung Electronics believed that it would be difficult to control a stable supply of TFT from this deal, so it changed its strategy and instead requested Samsung Display.

In addition, Samsung Electronics also told Samsung Display that it is more willing to accept Samsung Display’s official Supply of quantum dot (QD) OLED panels under development. This makes it difficult for Samsung Display to refuse the offer, as it needs customers for its QD-OLED, which is now close to commercial production.

At the same time, Micro LED TV uses micron-sized LEDs as light sources. Samsung launched its first phone in 2018, saying its first 146-inch phone featured Wall technology. Last year, it launched a 110-inch version for the domestic market.

Sources said Samsung expects to ship about 400 to 500 Micro LED TVs this year. This is 0.001% of the 49.27 million TV sets it shipped last year.