Flat-Panel Displays

Flat-Panel Displays

Emerging display technologies, such as OLEDs, touch screens and flexible TFTs, require improvements in thin film technology over the current performance of Si-based TFTs. ALD can speed up development and improve yield due to its repeatable, atomic-level control, along with its high film quality, uniformity, and conformality.

The Helios line of industrial systems enables, for the first time, high productivity, production-scale ALD manufacturing on large panels. Sundew’s SMFD-ALD technology enables low temperature deposition at throughputs comparable to sputtering and CVD, providing a superior performance, cost-competitive alternative.

Transparent Conductive Oxide

Indium tin oxide (ITO) is currently the dominant transparent conductor oxide (TCO) of choice. Increases in indium price, as well as the inherent limitations of ITO deposition drive the need for ITO replacements. ITO has limited resiliency and it tends to wear out and crack when bent. In addition, some of its electrical or optical properties, such as low carrier mobility and rough interface may be inadequate for some applications.

Sundew’s ZnO:Al provides a robust and stable ALD process for TCO applications, including organic light emitting diodes (OLEDs), touch screens, flexible displays and solar. Our SMFD-ALD systems give you the unmatched capability to deposit thick ZnO:Al ALD layers at low temperatures with high volume productivity. The Helios line is designed to deposit on large panel sizes, while the Apollo line is geared toward wafer deposition and handling.

Advantages and Benefits:

  • Fast deposition at LOW temperatures
  • Stable precursors
  • High yield, repeatable process with high alloying accuracy
  • Minimal setup and optimization time
  • Seamless alloying without throughput penalty
  • Highest quality films
  • Superior uniformity
  • 100% conformal coverage

OLED Encapulation

Organic light emitting diode (OLED) devices are extremely sensitive to moisture and oxygen and therefore must be protected with a high performance encapsulating layer. OLEDs require very low permeability levels — for example, water vapor transmission rates (WTVR) <10−5 g/m2•day.

Such low levels of permeability require extremely low pin-hole density. Atomic layer deposition is the only technique that can achieve this level with a film as thin as several hundred of angstroms. Sundew’s ALD-Cap® has been tested to < 10-6 gmxmm/m2/day WVTR on PET and PEN sheets and was applied to thousands of square meters of flexible polymer sheets for solar/OLED protection applications.

Advantages and Benefits:

  • 100% conformal
  • Ceramic films
  • Extremely low-permeability barrier to gases, moisture, and more (< 10-6 gmxmm/m2/day WVTR)
  • Flexible, applied to 1,000s of m2 of flexible PET/PEN sheets
  • Superior uniformity
  • Thin coating (200-500 nm)
  • Low temperature deposition (down to 70° C)
  • Atomic level control of film properties