Will TFT-LCD be replaced by AMOLED?(1)

Recently, there is a saying in the media and the industry that foreign AMOLED (active organic light-emitting display) products have been mass-produced and launched, and TFT-LCD (thin film transistor liquid crystal display) technology and products have fallen behind and will soon be replaced by AMOLED technology. To a certain extent, this has caused ideological confusion in China’s industry. Is this really the case?The following is an article by Wang Dongsheng, chairman of the Liquid Crystal Display Branch of the China Optoelectronics Society and chairman of BOE Technology Group.

In the past 15 years, there have been two directional debates in the display field. The first time it happened around 2000, when the color picture tube (CRT) industry was facing a crisis. Is the next mainstream direction to be plasma display (PDP) or TFT-LCD? There were two very different voices in the industry at the time. The development of more than 10 years has proved that TFT-LCD has become the mainstream in the display field, and PDP is declining day by day. Today, with the continuous emergence of new display technologies such as Flexible Display and Laser Display, especially the beginning of industrialization of AMOLED, there is a second battle for direction.


The key to TFT-LCD replacing CRT is the technical foundation

Since the advent of the transistor in 1947, the main line of technological evolution in the field of electronic devices has been the replacement of vacuum electronic technology by semiconductor technology. The key reason why TFT-LCD technology can stand out and become the mainstream of the display market is that it conforms to the general trend of semiconductor technology replacing vacuum electronic technology. Fifteen years ago, when BOE had a premonition that the CRT industry was coming to an end and decided to enter the new display field, some people suggested choosing PDP, while others recommended FED (vacuum microelectronic display). We believe that both PDP and FED are based on vacuum electronic technology, while TFT-LCD is based on semiconductor technology, which conforms to the general trend of technology substitution, so we choose the latter, thus establishing the correct strategic development path of BOE .

TFT-LCD and AMOLED belong to semiconductor display

Will the mainstream technology TFT-LCD in the current display market be replaced by the new generation display technology AMOLED? My point of view is: From CRT to TFT-LCD is the interruption and beginning of technology; but from TFT-LCD to AMOLED is the extension and development of technology. TFT-LCD, AMOLED, and new display technologies including flexible displays are based on semiconductor technology, so they can be collectively referred to as Semi-Display.

I define the new concept of “semiconductor display” as a general term for display technologies that independently control each smallest display unit through semiconductor devices. It has three basic features: one is to independently control the state of each display unit with semiconductor devices such as TFT arrays; the other is to use materials with semiconductor characteristics such as amorphous silicon, low-temperature polysilicon, oxide, and carbon; the third is to use semiconductor manufacturing technology .

We can also explain from the structure of the display device. Although the structure of AMOLED devices is simpler than that of TFT-LCD devices, its most important part, the semiconductor backplane, is developed on the basis of TFT-LCD technology, and the basic characteristics and technical basis of the two semiconductor displays have not changed. . With years of development, TFT-LCD semiconductor backplane technology has developed from the first generation to the third generation, thus providing a basic support for the development of AMOLED technology. The technical relevance and resources of the two in terms of materials, processes and equipment Sharing up to 70%. Therefore, AMOLED is just the extension and development of TFT-LCD technology, and the basic technology of both is semiconductor.

Post time: Mar-06-2023