THE EVE OF THE OLED PANEL "REVOLUTION": LTPO TECHNOLOGY HAS BECOME THE NEW FOCUS OF THE SINO-KOREAN GAME

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Jiwei Network reported that in recent years, display technologies such as LCD, OLED and AMOLED screens have become more and more competitive, and even various products have been dazzling. With the continuous iterative upgrading of various panel technologies, how will the next generation of mobile phone screens evolve? At this stage, LTPO OLED screens with better picture quality, lower power consumption and smoother operation have become one of the ideal choices.

In terms of LTPO technology, South Korea's Samsung and LG currently have advantages in terms of yield, cost and capacity. However, from 2022, with the localization of LTPO products, Chinese companies will get more chips to compete with Korean companies on the OLED track. As a result, on the eve of the OLED panel "revolution", LTPO technology has become a new focus of the Sino-Korean enterprise game.

LTPO technology advantages are "innate"

At present, a new generation of display technology is developing in the direction of high resolution, fast response speed, high contrast, flexibility and ultra-thin. In the main preparation process of OLED panels - LTPS and oxide TFT, the former has become the main technology of small and medium-sized screens such as smart phones and smart watches because of its high electron mobility, opening rate and ability to achieve higher resolution.

However, excessive power consumption is still a major problem that LTPS is difficult to avoid when driving OLED. Specifically, LTPS has a relatively high amount of open-state current and relatively large leakage, so it is necessary to continuously charge to maintain the potential in the capacitor to avoid poor panel image quality. This means that LTPS cannot achieve low-frequency drive, which is very detrimental to panel power savings.

Due to its advantages of large-area preparation, good bending characteristics, low cost and easy integration, oxide TFT (mainly IGZO) was once considered the most advantageous alternative. However, it is understood that its electron mobility is not high enough, and the photoelectric stability is not good enough, so it has always wandered in the field of large-size OLED panels, and has not really stepped on the stage of small and medium-sized OLED.

Image source: BOE Innovation Hub

Today, the "killer" new technology has arrived. Li Leiguang, chief analyst of the display industry of Jiwei Consulting, said that as a TFT drive technology combined with LTPS and IGZO, LTPO combines the advantages of these two major schools at the same time, can achieve higher charge mobility, stability and scalability, and has inherent competitiveness in terms of life, brightness, resolution and low power consumption.

In terms of performance, ltpo OLED screen refresh rate up to 120Hz, while supporting hardware variable refresh rate (VRR), fixed the ltsopsis OLED non-adjustable refresh rate shortcomings. For example, the refresh rate can be reduced to a minimum of 1Hz when using a static scene. Thanks to this, LTPO under the same conditions can save about 10%-15% of power consumption compared to LTPS technology.

However, because the LTPO process needs to consider the interaction between LTPS and IGZO device processes, Li Leiguang believes that the OLED of LTPS backplane technology has not been perfectly solved in terms of yield. LTPO as a newer technology has not yet been fully mastered, the production process still needs to be re-explored, and yield improvement and cost control still need to be worked on.

Korean companies are scrambling to lay out LTPO production capacity

In the 5G era, with the significant increase in power consumption, LTPO OLED technology with advantages such as low power consumption has become one of the important choices for mobile phone manufacturers. However, due to factors such as production capacity and cost, there are only a few mobile phones that apply this screen in 2021 - Samsung Note20 Ultra, S21, OPPO Find3 X, OnePlus 9 series and iPhone 13 series parts.

It can be said that LTPO technology has gradually become the mainstream configuration of flagship models such as folding screens, and will become the standard for high-end mobile phones in the future. This is because folding screen phones require a high refresh rate to reduce the latency of larger size screens, and high refresh rate is also a standard parameter for flagship phones. In addition, due to the large number of static low refresh rate scenarios, wearable products are also one of the main applications of LTPO.

As the evolution direction of OLED panel technology, LTPO technology has been in the industry outlet. Li Leiguang said that due to the exploration and improvement of mass production technology, LTPO OLED has not yet been applied on a large scale. But it is not far from large-scale application, and I believe it will be within the next two years. If LTPO technology matures further, it will be possible to completely replace LTPS backplanes.

Sigmaintell data also shows that global LTPO smartphone shipments will be about 53 million units in 2021, and it is expected that global shipments will be about 140 million units in 2022, an increase of 156% year-on-year. In addition, Omdia predicts that from 2024, the flexible OLED using LTPO backplanes will exceed the flexible OLED using LTPS backsheets.

Based on this, even if the replacement of LTPO OLED production line requires a lot of additional investment, Korean companies are still actively expanding production. According to data from UBI Research, a market research agency, in 2020, Samsung's dedicated 6th generation line for Apple has a production capacity of 30,000 LTPO panels. In 2021, Samsung will transform Apple's dedicated line to significantly increase production capacity.

In addition, in order to reduce the risk of LTPO screen supply chain and improve bargaining power, Apple has earlier jointly developed LTPO screen with LGD. To this end, LGD also invested in the expansion of E6-3 production in July 2021 and introduced more LTPO OLED panel production equipment. After the completion of the renovation, the production of its OLED panels will increase by 50%, and it is expected to be put into production in the second half of 2022.

LTPO has become a new focus of the Sino-Korean industrial game

In the competition of OLED display tracks, Samsung and LGD are currently in a leading position. However, domestic manufacturers have been catching up, and their comprehensive strength and market share have been growing rapidly in recent years. According to the statistics caliber of the Korea Display Industry Association, the market share of AMOLED panels of smart phones of Chinese panel manufacturers was only about 1.1% in 2016, but it has reached 13.2% in 2020.

In 2021, BOE successfully broke into the "fruit chain" and officially became an iPhone 13 screen supplier, marking the breaking of the iPhone screen supply pattern dominated by Korean companies. However, according to industry sources, the supply of BOE for Apple does not involve LTPO OLED screens. As a result, domestic panel manufacturers urgently need to accelerate the breakthrough of LTPO mass production technology.

The good news is that many domestic manufacturers are expected to mass-produce LTPO screens in 2022. In November last year, it was reported that BOE was rebuilding the production lines of the B7, B11 and B12 factories, and planned to transform the LTPS production line into an LTPO production line. In addition, Visionox Hefei production line already has the ability to mass-produce GOODS with LTPO OLED, and currently reserves 20K/month LTPO production capacity.

For the first time, it is equipped with the Honor Magic4 series of domestic LTPO screens

For the competition in the display panel industry, Li Leiguang believes that at present, Samsung and LGD have experience in the mass production of LTPO backplane OLED, and they have more advantages in the input and mass production of OLED. Undoubtedly, compared with the two companies in South Korea, there is indeed a certain gap between domestic panel companies, but in the process of catching up, this gap will become smaller and smaller, and even achieve overtake in the future.

In addition, some industry insiders said that the technical gap between China and South Korea is now about three years, but as the LTPO screen begins to be localized, the gap will be further narrowed. It is understood that from 2022 to 2023, BOE, Visionox, Huaxing Optoelectronics, Tianma and other manufacturers will successively launch LTPO products, and will accelerate the penetration of LTPO OLED screens in China.

According to the report released by CINNO Research, in 2021, the proportion of OLED smartphones equipped with LTPO panels in the Chinese market will be 7%; it is expected that by 2025, OLED products using LTPO technology will surpass OLED products using LTPS technology, and the penetration rate is expected to reach 43%. Undoubtedly, the Chinese market will become an important support point for domestic panel companies.

epilogue

In the OLED panel industry, domestic manufacturers are also making more attempts and challenges in the competition with Korean companies. It is reported that BOE plans to achieve mass production of double-layer series OLED displays in the second half of 2022. Compared with single-layer OLED panels, the screen brightness of the double-layer series OLED panel can be increased by 2 times, the service life can be extended by 4 times, and the power consumption can be reduced by up to 30%.

With the increasingly fierce competition in the industry and the increasingly complex external environment, domestic panel manufacturers keep up with the trend of technology and mature rapidly to help improve China's global competitiveness. With the exploration of cutting-edge technologies such as LTPO and double-layer tandem OLED, Chinese companies may compete with Korean companies on the OLED track in the next few years, just like in the LCD LCD industry! (Proofreading/Hidden Dracy)