September 25, 2012 – Linde Electronics, a unit of the Linde Group, has added a new high-purity nitrous oxide (N2O) plant in Zhenjiang, Jiangsu Province, China to help support increased adoption of metal oxide transistors by display manufacturers.
The new plant follows an expansion of a plant in Taiwan and another one being built in Korea; the two plants in China will be managed by Linde LienHwa, a joint venture with LienHwa MiTAC Group in Taiwan. Linde and LLH are currently running six N2O plants in Asia with a capacity of more than 3,000 tons per year; the three new plants will boost design capacity to more than 10,000 tons per year.
Improving electron mobility in transistors is crucial in bringing higher resolutions and higher frame rates to TVs, mobile and computing devices. Making next-generation ultrahigh-definition 3D TFT/LCD and OLED displays is currently expensive, requiring the use polysilicon transistors which cost twice as much as those using amorphous silicon. Replacing polysilicon with metal oxide can increase electron mobility by a factor of up to 40 compared with conventional technology, at a comparable cost. Metal oxide transistor manufacturing requires high volumes of high-purity N2O to create functional layers of the microscopic thin-film transistors required to control each of the millions of pixels that make up the visible image.
The metal oxide transistors also allow more light to pass from the backlight through the backplane, reduce power consumption, and increase battery life of mobile devices. Moreover, they also allow the higher currents needed to drive OLEDs. Most display makers have or are working on products with metal-oxide transistors — Samsung and LG both have 55-in. OLED TVs, and Sharp has begun commercial production of metal oxide displays in its Kameyama plant.
"The shift from silicon to metal oxide transistors would not be possible without a secure supply of high-purity N2O, which highlights the critical role that specialist gases play in enabling the development of next-generation consumer electronic devices," stated Andreas Weisheit, head of market development for flat-panel displays at Linde Electronics.