ALD

This is a sponsored post by Ergis Group

In 2020, Poland-based Ergis Group launched the noDiffusion film platform, a high-barrier film that offers high level of optical transmittance and low level of light scattering, and the ability to contain transparent conductive electrodes. The new technologies adopted in the production of the barrier films offer a combination of high performance and competitive pricing.

Ergis has been busy since 2020, scaling up its production capabilities, and progressing towards production in a roll-to-roll configuration (rather than the batch system it used before). Ergis is using two different technologies - ALD and sputtering to deposit the barrier and the conductive electrodes.

Researchers from the Korea Advanced Institute of Science and Technology (KAIST) developed a self-powered wearable and washable OLED display device. The whole device is fabricated on textiles and the efficient OLED devices are driven by polymer solar modules.

Both the OLED device and the polymer solar panels are sensitive to moisture and oxygen, and regular OLED encapsulation will not protect such a device when washed. The researches designed a new washable encapsulation barrier using both ALD and spin coating. The device is flexible (curvature radius of 3 mm) and survived 20 washing cycles of 10 minutes each with little change in performance.

Graphene is the world's most impermeable material, and as the material is also transparent, flexible and ultra-thin it makes sense to adopt graphene as an encapsulation layer for next-gen OLED displays. A UK project led by Cambridge University researchers have set out in 2015 to develop such a solution, and the researchers now report that they have demonstrated a viable graphene solution comparable to existing commercial OLED encapsulation technologies.

In its pure form, graphene is permeable to all gases, but real life materials are never entirely pure and defects and holes harm the material's permeability. The new research used ALD and CVD to create large-area high-quality single-layer graphene sheets which were stacked to create a multi-layer coating. The researchers say that a ~10 nm barrier layer that includes 3-4 layers of graphene (with AlOx in between) is an effective solution for OLED displays. The 10 nm layer maintains a high optical transparency (>90 %) and high flexibility.

UBI Research says that as OLED makers are diverting all efforts into flexible OLED production, thin film encapsulation (TFE) is gaining in popularity. Between 2017 and 2021, TFE will be applied to about 70% of all OLED panels in production. The OLED encapsulation equipment market will generate $11 billion in sales.

TFE encapsulation started out as a complex technology that required 11 layers and was slow and expensive. Recent advances allowed OLED makers to reduce the number of layers to just 3 and increase productivity and yields and so lower the production costs. Some film OLED makers opted for hybrid encapsulation (which uses a barrier film) but TFE seems to have become the technology of choice.

ALD equipment maker Encapsulix announced that a leading Asian AMOLED manufacturer has chosen its ALD-TFE deposition systems, to be used as flexible AMOLED encapsulation. The first tool is already under construction and will start operating in the spring of 2017.

Encapsulix says that the order was awarded following an extensive evaluation of available ALD platforms, and this confirms the technological superiority and leading cost-of-ownership of the company's ALD-TFE equipment.

Researchers from South China University of Technology (SCUT) demonstrated a new MgO-based OLED encapsulation layer. The researchers say that MgO provides an efficient barrier at a low cost, and can be deposited in low temperatures.

The researchers say that this is the first time that MgO is used for OLED encapsulation, but this material has a number of advantages - a low refractive index, a wide bandgap, high dielectric constant, high chemical stability and the lack of UV irradiation treatment requirements.