Oxide TFT

UK-based SmartKem develops a new class of flexible high-mobility OTFT display backplane technologies. The company provides customized solutions involving molecular synthesis, electronic prototyping and on-site technology transfer support.

As Smartkem is developing new backplane materials for OLEDs, ePaper and mini-LED devices, we discuss its technology and business with the company's CEO and chairman, Ian Jenks.

Samsung Display is updating its A3 flexible OLED production line, to support two new technologies. The TFT process is being updated, for some of the capacity, to Apple's LTPO technology. LTPO is currently used in Apple's Watch displays, but next-generation iPhones will adopt it as well.

According to UBI, Samsung will dedicate 75,000 monthly substrates to produce smartphone LTPO displays. According to some reports, Samsung has also developed its own backplane technology which is similar to LTPO, it could be that some of this capacity will be used for Samsung's own displays.

Update: It seems we were mistaken, this prototype is not a hybrid QD-OLED, but a 'regular' OLED. This is still an impressive development - a rollable inkjet-printed OLED display.

TCL and Juhua Printing demonstrated a 31" FHD inkjet-printed rollable hybrid QD-OLED TV prototype. The display uses an IGZO (Oxide-TFT) backplane and TCL says that it has an aperture ratio of over 50%, brightness of 200 nits and a 90% DCI-P3 color gamut.

TCL's hybrid display technology (which TCL calls H-QLED) uses a blue OLED emitter coupled with red and green QD emitters. All three emitter materials are combined and printed using ink-jet printing technology.

Researchers from the Holst Center has applied spatial atomic layer deposition (sALD) to create both the semiconductor and dielectric layer in a thin-film transistor (TFT) Oxide-TFT (IGZO) display backplane - for the first time ever.

The researchers created a 200 PPI QVGA OLED display prototype on a thin PEN foil. This shows how TFTs can be produced in a low temperature process (below 200 degrees Celsius) using sALD on a cheap transparent plastic foil. The TFTs achieved a mobility of 8 cm²/V2 with channel lengths down to 1 um.

Sharp announced that it has developed, in collaboration with NHK, a 30" rollable 4K OLED panel on an IGZO backplane. This is a direct emission OLED, which sharp says is the world's largest ever produced (LG's OLEDs all use color filters).

Sharp's OLED panel is deposited on a thin-film substrate, and has a thickness of 0.5 mm. The display uses NHK's signal processing and panel driving technologies to "improve the brightness uniformity and video clarity".

Sharp demonstrated a flexible 12.3" 1920x720 AMOLED display for automotive applications. The displays uses an IGZO backplane, and Sharp says that it intends to use external compensation to improve the uniformity in the display.

Sharp demonstrated the display at the 2019 Vehicle Displays and Interfaces Symposium - at which apparently this was the only OLED on display. According to Display Daily's Ken Werner, OLED displays are finding it difficult to penetrate the automotive display market.

Japan's Semiconductor Energy Laboratory (SEL) is developing several exciting OLED technologies, and the company demonstrated its latest panels at SID DisplayWeek. The recently published video below shows the company's OLED technologies shown at the event:

First up is the world's smallest 8K display, a 8.3" OLED (1058 PPI) with a resolution of 7680x4320. The panel is based on a white OLED with color filter architecture and SEL's proprietary CAAC-IGZO (c-axis aligned crystalline In-Ga-Zn-O) backplane material.

China-based display maker CSoT demonstrated several new OLED display prototypes and technologies at SID 2019, and this great new video shows these displays in action.

First up is a 31" 4K (3840 x 2160, 144 PPI) AMOLED that was produced using an ink-jet printing process on an IGZO substrate. The peak brightness is 200 nits and the refresh rate is 120 Hz. This seems to be the same panel announced in March 2018 by Joshua Printing Display Technology (established by CSoT and Tianma in 2016). The display has some noticable defects.

In March 2019 we reported that LG Display has delayed its plans for its $10 billion P10 10.5-Gen OLED TV fab in Paju, as the new larger deposition process was a larger challenge than expected.

According to a new report from Korea, LG display has actually started to install some of the Oxide-TFT deposition equipment (supplied by Applied Materials and Jusung Engineering) earlier than it first planned. LGD's original plan was to install this equipment in early 2020. The mass production at the P10 fab is expected to begin in 2021.

CSoT demonstrated the first public QD-OLED display, during SID 2019. The company unveiled a 6.6" display that features a relatively low resolution (384x300) and brightness (50 nits). The backplane of this prototype is an Oxide-TFT.

The QD-OLED is made from blue OLED emitters with a quantum-dots color conversion layer. This is a similar design to Samsung's QD-OLED TV technology. Interestingly earlier this year CSoT's parent company TCL has unveiled a different QD-OLED technology it refers to as H-QLED which uses a combination of OLED and QD emitters.