Displays
Semitronics partners offer a range of applications within display technology. Semilab who provide the metrology required for accurate TCO measurement. PulseForge enable flexible displays with a debonding process, which separates the flexible substrate from the rigid carrier. XTPL is developing next generation transparent conducting films, fine line printing of wrap around edge contacts, along with accurate deposition of quantum dot materials.
Metrology in Displays
Semilab has developed a wide range of technologies to monitor the production of flat panel displays by checking various optical and electrical properties of the layers during manufacturing. For this purpose a separate product line, the Flat Panel Tester tool was designed. It offers advanced measurement capabilities on large area substrates, integrated into the fab environment. In addition to this, lab tools are available for R&D and offline quality control.
IGZO Electrical Characterisation:
IGZO is one of the state-of-the-art active layer for display industry. However even today the fine tuning of the process requires very precise measurements in order to maintain the best layer properties. Using Semilab’s µ-PCR and contact sheet resistance measurement one can map the panel with a reasonable speed which can show the improper settings of the layer deposition and set up the possibilities for further optimization µ-PCR can determine a parameter (amplitude) which related to the device mobility, moreover other layer quality parameters (calculated from the microwave response decay curve) can be calculated as well.
Printed OLED Sub-Pixel Characterisation
Printing OLED is very attractive way for producing organic layer containing devices due to its low price and relatively easy technique. However, in many cases the uniformity of printed layers is much worse than the conventionally manufactured layers. Semilab has developed a metrology which can determine the full thickness of OLED structure in one sub-pixel using a single measurement in a few seconds. The lateral resolution can be as high as 5 µm which allow to our customer to fine tune precisely the printing process.
Sheet Resistance Measurement
The combination of the ion implant process and the process to anneal implants is usually monitored by measuring the sheet resistance of the implanted layer. The sheet resistance varies with dose, energy, and the amount of implanted species that has become electrically active. It is the sheet resistance that ultimately determines the device performance. Thus, measuring sheet resistance is an excellent way to monitor everything associated with an implant process.
Transparent Conductive Films (TCFs)
XTPL is developing next generation TCF technology which will facilitate manufacturing of displays allowing for true flexibility and independence from rare and expensive indium. This new technology offers full optical transparency, excellent conductivity, full flexibility and low production costs using lower cost materials such as silver.
Image of 10 cm x 10 cm TCF sample obtained from Ag/Cu mesh with sheet resistance 22 Ohm/sq and optical transmission 93%. The width of printed lines is 5 µm and interlines distance is 500 µm. TCF was printed on the glass.
Quantum Dots
With XTPL additive technology you are able to dispense quantum dots material with unparalleled precision, versatility and simplicity
Nano crystals are implemented in high-quality flat panel displays and other various consumer devices. Higher efficiency and enhanced color quality are the abenefits of quantum dots based displays. When the typical blue LED light is shone through a layer of quantum dots, the crystals break down the light and produce a richer white light that contains all the colors of the spectrum. This light then results in a better picture quality with darker blacks and more vibrant non-blue colors. Quantum dot displays use around 20-30% less power in comparison to standard LCDs. QLEDs emit up to 90% less blue color light than LCDs and therefore are much human-eye friendly. In most cases quantum dots will be implemented on another layer of film just above the backlight.
