Gritty Amir never gives up … although he has now been working
day and night @ 365/7, he got one more key paper under his belt! In the world
of TFT for displays, performance (output current) is an important requirement.
Traditional way of achieving that depends a lot on scaled devices. In case for
TFTs for display, that would be cost prohibitive. Thus, we have shown that a
vertical array of TFTs which are also laterally connected (in a wavy
architecture) can achieve higher output current (as we are increasing the TFT
width without an iota of geometric area increment). We have shown both its
theoretical promise and experimental validation in material antagonistic way,
this time, Amir
et al. have shown it on flexible substrates using a low
thermal budget process integration sequence which controlled LEDs.
Wavy Architecture Thin Film Transistor for Ultra-High
Resolution Flexible Display
Amir Nabil Hanna, Arwa
Talal Kutbee, Ram Chandra Subedi, Boon Ooi and Muhammad Mustafa Hussain
A novel wavy shaped thin-film-transistor (TFT) architecture,
capable of achieving 70% higher drive current per unit chip area when compared
to planar conventional TFT architectures, is reported for flexible display
application. The transistor due to its atypical architecture does not alter the
turn-on voltage or the OFF current values, leading to higher performance
without compromising static power consumption. The concept behind this
architecture is expanding the transistor’s width vertically through grooved
trenches in a structural layer deposited on a flexible substrate. We show
operation of Zinc Oxide (ZnO) based TFTs down to a bending radius of 5 mm with
no degradation in the electrical performance or cracks in the gate stack. We
finally demonstrate flexible low power LEDs driven by the respective currents
of the novel wavy, as well as, conventional coplanar architectures, where the
novel architecture is able to drive the LED at 2× the output power, 3 mW vs.
1.5 mW, which demonstrates the potential use for ultra-high resolution displays
in an area efficient manner.
Way to go, Amir!