OLED display encapsulation with the optical property

Abstract

A process of making an optical film or optical array comprises: a) simultaneously directing a series of gas flows along elongated substantially parallel channels to form a first thin film on a substrate; wherein the series of gas flows comprises, in order, at least a first reactive gaseous material, an inert purge gas, and a second reactive gaseous material; wherein the first reactive gaseous material is capable of reacting with a substrate surface treated with the second reactive gaseous material to form the first thin film; b) repeating step a) a plurality of times to produce a first thickness of a first film layer with a first optical property; wherein the process is carried out at or above atmospheric pressure; c) repeating steps a) and b) to produce a second film layer; and wherein the process is carried out substantially at or above atmospheric pressure.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]Reference is made to commonly-assigned copending U.S. patent application Ser. No. 11 / 392,007, filed Mar. 29, 2006, by David Levy, entitled PROCESS FOR ATOMIC LAYER DEPOSITION; U.S. patent application Ser. No. 11 / 392,006, filed Mar. 29, 2006, by David Levy, entitled APPARATUS FOR ATOMIC LAYER DEPOSITION; U.S. patent application Ser. No. 11 / 620,744, by David Levy, entitled DEPOSITION SYSTEM AND METHOD USING A DELIVERY HEAD SEPARATED FROM A SUBSTRATE BY GAS PRESSURE; and U.S. patent application Ser. No. 11 / 620,740, by Nelson et al. entitled DELIVERY DEVICE COMPRISING GAS DIFFUSER FOR THIN FILM DEPOSITION; the disclosures of which are incorporated herein.FIELD OF THE INVENTION[0002]This invention generally relates to thin film devices and components, such as electronic light emitting displays, sensor arrays, and other electronic devices, environmental barrier layers, optical thin film layers, where thin-film layers are made by vapor depositio...

AI Technical Summary

Benefits of technology

[0038]In an effort to minimize the time that an ALD reaction needs to reach self-termination, at any given reaction temperature, one approach has been to maximize the flux of chemicals flowing into the ALD reactor, using so-called “pulsing” systems. In order to maximize the flux of chemicals into the ALD reactor, it is advantageous to introduce the molecular precursors into the ALD reactor with minimum dilution of inert gas and at high pressures. However, these measures work against the need to achieve short cycle times and the rapid removal of these molecular precursors from the ALD reactor. Rapid removal in turn dictates that gas residence time in the ALD reactor be minimized. Gas residence times, τ, are proportional to the volume of the reactor, V, the pressure, P, in the ALD reactor, an

Problems solved by technology

However, the materials comprising the organic EL element are sensitive and, in particular, are easily destroyed by moisture and high temperatures (for example greater than 140 degrees C.).

In contrast, typically polymeric materials have a moisture permeation rate of approximately 0.1 gm/m2/day and cannot adequately protect the OLED materials without additional moisture blocking layers.

However, such protective layers also cause additional problems with light trapping in the layers since they may be of lower index than the light-emitting organic layers.

While multiple layers provide better protection for OLED displays, thicker layers diminish transparency and as a result brightness and color saturation of the display.

In practice, in any system it is difficult to avoid some direct reaction of the different precursors leading to a small amount of chemical vapor deposition reaction.

Self-saturating surface reactions make ALD relatively insensitive to transport non-uniformities, which might otherwise impair surface uniformity, due to engineering tolerances and the limitations of the flow system or related to surface topography (that is, deposition into three dimensional, high aspect ratio structures).

As a general rule, a non-uniform flux of chemicals in a reactive process generally results in different completion times over different portions of the surface area.

However, in spite of its inherent technical capabilities and advantages, a number of technical hurdles still remain.

However, it is difficult to obtain a reliable scheme for introducing the needed se

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