New TFT technology could replace LTPS for OLED, LCD, and solar devices

July 1, 2018
New thin-film-transistor (TFT) technology will increase efficiency and luminance while decreasing cost.

Solar-Tectic (ST; Briarcliff Manor, NY), with assistance from Binghamton University (Binghamton, NY) and Blue Wave Semiconductor (BWS; Baltimore, MD), has patented new thin-film-transistor (TFT) technology that will increase efficiency and luminance while decreasing cost for organic light-emitting diodes (OLEDs), active-matrix OLEDs (AMOLEDs), and liquid-crystal device (LCD) displays, as well as solar cell devices.

Unlike conventional low-temperature polysilicon (LTPS) processes used to manufacture the TFTs that drive the pixels in a display and require expensive excimer-laser annealing, the new process is a variation of metal-induced crystallization (MIC) and uses a modified liquid-phase-epitaxy (or vapor-liquid-solid) electron-beam process at low temperature (as low as 232°C) to deposit a thin layer of metal onto a metal oxide such as a magnesium oxide (MgO) buffered substrate, after which the final vaporized silicon (Si) layer is deposited and crystallizes into an approximately 50- to 100-nm-thick film without metal residue. Using Raman and x-ray spectroscopy, analysis of the Si film revealed a very high electron mobility of 188 cm2/Vs (compared to the typical 100 cm2/Vs for LTPS). The researchers expect to improve electron mobility even further by using ST’s and BWS’s oriented MgO (111) film buffered substrates to further increase crystal size. Reference: P. P. Rajbhandari et al., Mater. Lett., 219, 138–142 (2018).

About the Author

Gail Overton | Senior Editor (2004-2020)

Gail has more than 30 years of engineering, marketing, product management, and editorial experience in the photonics and optical communications industry. Before joining the staff at Laser Focus World in 2004, she held many product management and product marketing roles in the fiber-optics industry, most notably at Hughes (El Segundo, CA), GTE Labs (Waltham, MA), Corning (Corning, NY), Photon Kinetics (Beaverton, OR), and Newport Corporation (Irvine, CA). During her marketing career, Gail published articles in WDM Solutions and Sensors magazine and traveled internationally to conduct product and sales training. Gail received her BS degree in physics, with an emphasis in optics, from San Diego State University in San Diego, CA in May 1986.

Sponsored Recommendations

Request a quote: Micro 3D Printed Part or microArch micro-precision 3D printers

April 11, 2024
See the results for yourself! We'll print a benchmark part so that you can assess our quality. Just send us your file and we'll get to work.

Request a free Micro 3D Printed sample part

April 11, 2024
The best way to understand the part quality we can achieve is by seeing it first-hand. Request a free 3D printed high-precision sample part.

How to Tune Servo Systems: The Basics

April 10, 2024
Learn how to tune a servo system using frequency-based tools to meet system specifications by watching our webinar!

Precision Motion Control for Sample Manipulation in Ultra-High Resolution Tomography

April 10, 2024
Learn the critical items that designers and engineers must consider when attempting to achieve reliable ultra-high resolution tomography results here!

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!