OLED (Organic Light Emitting Diodes) is a flat light emitting technology, made by placing a series of organic thin films (usually carbon based) between two conductors - and these films light up when electrical current is applied. OLEDs are used to make display and lighting panels. OLED displays are thinner, more efficient than LCD displays, and they offer a far better image quality.

One of the most exciting features of OLED displays is that they can be made flexible. Can you image foldable phones that open to become tablets, TVs that can be rolled up when not in use and lighting panels that wrap around round pillars? Flexible OLEDs can enable all of that, and more.

One of the major problems with those organic materials is that they are very sensitive to oxygen and moisture. This means that OLEDs need to be protected - as even a single water or oxygen molecule can harm the OLEDs.

Thin Film Encapsulation (TFE)

With regular - rigid - OLED panels, the solution is simple - you can use a strong glass sheet. Glass is a great barrier, and it is widely used in the display industry and so easy to process. The glass used in current display and lighting panels is rigid and not very durable. So companies are looking for alternatives to standard glass encapsulation materials. Flexible OLED encapsulation is actually one of the major challenges towards cost effective mass production of flexible displays.

There are several technologies that enable thin-film encapsulation (TFE) suitable for flexible OLED displays:

  • Vacuum Polymer Technology: developed at Vitex and bought by Samsung in 2010, this is the technology currently used by Samsung. It is a multi-layer barrier that is relatively slow to deposit as it requires several stages (SDC recently managed to reduce them from 6 to 3) and so Samsung is looking to replace it with a more cost effective solution.
  • LG's Faceseal: LG's own encapsulation technology, this is a a multi-layered organic and in-organic film. LG Display currently uses Faceseal for both flexible OLED display and lighting panels.
  • Atomic Layer Deposition (ALD): ALD can be used to quickly and efficiently deposit barrier films on flexible substrates. Several companies are developing OLED encapsulation systems based on ALD. One example is Veeco with their FAST-ALD tech (which they acquired in 2013 for $185 million) which is being evaluation by Samsung. Other OLED ALD developers include Beneq and Encapsulix.
  • Ink Jet Printing: While ink-jet is usually associated with micro-scale patterning, it can also be used to accurately and efficiently deposit encapsulation layers. In November 2014 Kateeva launched an Ink Jet Printing based Encapsulation system, and already shipped a mass-scale system - presumably to Samsung Display.
  • PECVD: Plasma Enhanced Chemical Vapor Deposition (PECVD) is another deposition technology that can be adapted for encapsulation barrier films. In 2015 Aixtron acquired PlasmaSi, a PECVD OLED encapsulation developer - and plans to incorporate those systems into its OLED deposition clusters.
  • UniversalBarrier: This technology, developed by Universal Display (UDC), can be used to deposit single-layer encapsulation films. According to the latest update from UDC, the technology is not yet ready for mass production, but it is already being evaluation by Samsung Display.
  • Flexible glass: Yes, it is possible to make flexible glass - which is a great barrier, but still not as durable as thin-film encapsulation materials. Corning for example is promoting its Willow Glass as a possible flexible glass encapsulation (and substrate) technology.

LG Chem truly flexible OLED lighting panel photo

Further reading

Latest OLED Encapsulation news

Idemitsu Kosan and Toray to co-develop OLED materials

Sep 26, 2017

Japan-based OLED material maker Idemitsu Kosan announced a new partnership with Toray Industries to co-develop OLED materials.

Toray and Idemitsu will mutually utilize the OLED materials, technology and expertise that both companies possess, and will cooperate in the development of new materials and material evaluation. The two companies will also jointly use their evaluation facilities and production facilities. Both companies hope that this collaboration will accelerate OLED material development and enable lower cost production.

The Fraunhofer FEP, NSMAT and MSSMC developed an OLED on a stainless steel substrate

Sep 21, 2017

The Fraunhofer FEP institute, in collaboration with Nippon Steel & Sumikin Materials (NSMAT) and Nippon Steel & Sumitomo Metal Corporation (NSSMC), developed a new OLED lighting prototype that is made on a stainless steel substrate.

OLED on stainless steel prototype (Fraunhofer, NSMAT, NSSMC)

The researchers say that a stainless steel substrate has several advantages compared to glass or plastic - it has excellent thermal conductivity and excellent barrier properties. The lighting panel features an extremely homogenous OLED light, thanks to the planarization layer developed by NSSMC. The prototype panel was produced at the Fraunhofer's R2R research line.

Flexbile OLEDs Market Report

CSoT orders OLED deposition equipment from AP Systems for its 6-Gen flexible AMOLED fab in Wuhan

Sep 19, 2017

AP Systems announced that it has received orders for OLED deposition equipment from CSoT for the company's 6-Gen flexible AMOLED fab in Wuhan that is currently under construction.

AP Systems ELA system photo

AP Systems said that the whole order is worth $60.65 million and the equipment will be delivered starting in September 2017 until October 2018. AP Systems did not disclose the equipment list, but the company's main products are laser annealing equipment (used to produce LTPS substrates), laser list-off equipment and OLED encapsulation tools.

IHS: The OLED encapsulation material market will grow at a 16% CAGR to reach $233 million by 2021

Aug 31, 2017

According to IHS, the OLED encapsulation material grew 4.7% in 2017 to reach $117 million. IHS expects the market to grow at a 16% CAGR to reach $233 by 2021.

OLED encapsulation material market forecasts (IHS, 2016-2021)

The market growth rate will increase as new OLED fabs begin operation in China and Korea. IHS categorizes OLED encapsulation materials into metal, frit glass, TFE and hybrid. The metal type is mostly used for OLED TVs, in which IHS expects the fastest growth in terms of substrate size. Glass encapsulation will remain strong but will lose market share in the future.

Truly sees large demand for PMOLED displays, to dramatically increase capacity by next year

Aug 27, 2017

OLED maker Truly Semiconductor, based in Hong Kong, sees a large increase in PMOLED demand in the near future, and the company is executing an ambitious PMOLED capacity expansion plan.

Truly is currently operating two production lines: the P1 and P2 lines, both 2.5-Gen and with a monthly capacity of 625K and 1.25M pcs (Truly counts its capacity as per 1" displays). Truly has set out to build two new production lines. The P3 line which is a 2.5-Gen line with a capacity of 3.13 million 1” panels monthly is almost ready and will start mass production by the end of the month.

UBI Research sees PECVD as the in-organic TFE equipment of choice for flexible OLED production

Jul 29, 2017

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.

PECVD oled encapsulation market share (UBI, 2017-2021)

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.

The US DoE awards five new OLED project grants

Jul 24, 2017

The US Department of Energy announced 11 new solid state lighting projects grants, out of which five are related to OLED technologies (the rest are for new LED technologies).

OLED Devices Ascend OLED desk lamp photo

We already posted on two of these grants which were awarded to Pixelligent. In addition to Pixelligent, OLEDWorks were also awarded with two SBIR Phase 1 projects, one for an ultrathin, curved, high-efficiency OLED light engine that will reduce the cost OLED lighting and the second for the development of a novel substrate and encapsulation process.

Fraunhofer FEP develops a high-accuracy fingerprint sensor based on its bi-directional OLED microdisplays

May 04, 2017

The Fraunhofer FEP institute in Germany first unveiled its bi-directional OLED microdisplays in 2012 with the novel idea of embedding photo detectors between the OLED pixels. Since then the instituted demonstrated its second-generation microdisplay that supported a resolution of 800x600 (SVGA), up from VGA in the first generation prototypes.

Bi-directional OLED microdisplay (Fraunfhoer FEP, 2017)

The Fraunhofer FEP now announced that it developed a new generation of these displays, that employ an extra-think encapsulation layer, which can turn these new displays into fingerprint sensors. The idea is that the OLED display illuminates the fingers and then the reflected light is used to detect and analyze the fingerprint with excellent accuracy.

Kateeva doubles its manufacturing space in order to meet the demand for its OLED inkjet systems

Mar 09, 2017

OLED ink-jet developer Kateeva announced that it expanded its headquarters in silicon valley - in fact it doubled its manufacturing space in order to meet the demand for its inkjet systems.

Kateeva YIELDJet TFE system photo

Kateeva leased a new building adjacent to its HQ adding 75,000 sq. ft - mostly for manufacturing and business operations. Kateeva's current headcount has reached 330 people as orders for its YieldJet systems soared.

IHS sees the OLED production equipment market reaching $9.5 billion in 2017

Feb 10, 2017

IHS says that the OLED industry is now entering a huge capacity-growth phase, and IHS estimates that the AMOLED production equipment market will reach $9.5 billion in revenues in 2017.

AMOLED equipment revenue (2015-2018, IHS)

Almost half of that amount will go to TFT backplane equipment ($4.4 billion in 2017), while the organic layer deposition market will reach 2.2 billion and the encapsulation tools market will reach $1.2 billion. IHS estimates that Canon Tokki is the leader in OLED deposition equipment, and has a market share of over 50%.