This application claims the priority benefit of Chinese application No. 201210232494.7, filed on Jul. 5, 2012, titled with “method of manufacturing flexible display and substrate for manufacturing flexible display”. The entirety of the above-mentioned application are hereby incorporated by reference herein and made a part of this specification.
The present invention relates to flexible displays, and particularly to a method of manufacturing a flexible display and a substrate for manufacturing a flexible display.
Currently, many types of display technology can be applied in flexible display, including, for example, the traditional LCD technology, the bistable LCD technology, the OLED (organic light-emitting diode) display technology, the electrophoretic display technology, the electrochromic display technology, and the electroluminescent display technology. Compared with other flexible displays, FOLED (flexible organic light-emitting diode) display has more advantages, such as self-luminescence, fast response speed, high brightness, wide viewing angle, and low cost. Moreover, the FOLED display is based on the display of flexible organic materials, which can be curled, folded, or even as part of a wearable computer. Therefore, the FOLED display has a wide range of applications in portable products requiring good display effect and in special areas such as military field.
Traditional flexible display generally uses a flexible base material layer, for example, ultra-thin glass, stainless steel film, or a plastic substrate, with a thickness of less than 100 microns. Due to the fact that the flexible base material layer has the problems such as frangible, easy to get crinkled, and easy to deform, a rigid base material layer is generally required to affix together with the flexible base material layer in the actual manufacturing process to produce thin film transistor array and OLED on the flexible base material layer, and to package the thin film transistor array and the OLED. Finally, a suitable peeling method is used to peel the rigid base material layer off the flexible base material layer, to thereby finish the production of an FOLED display.
Accordingly, to properly affix the flexible base material layer with the rigid base material layer and peel the rigid base material layer off the flexible base material layer has become one of the key technologies in manufacturing a flexible display. The common method used to peel off the rigid base material layer includes laser irradiation method and water bath method. The laser irradiation method uses laser irradiation for heating the amorphous silicon film located between the flexible base material layer and the rigid base material layer, to cause the amorphous silicon film to become polycrystalline silicon to achieve the peeling. The water bath method uses water bath to cause a chemical reaction to the germanium oxide film located between the flexible base material layer and the rigid base material layer to achieve the peeling.
By continuous technological improvement, the above two peeling methods have improved the peeling effect to a certain extent in peeling the rigid base material layer off the flexible base material layer. However, by the above methods, the amorphous silicon film and the germanium oxide film cannot be completely and cleanly removed away, and the flexible base material layer is also easily subject to damage. Furthermore, process conditions in the above peeling methods are also difficult to control. As a result, the above peeling methods are ineffective in manufacturing high-quality flexible displays.
Therefore, the present invention provides a method of manufacturing a flexible display. The method includes forming a silicon sacrificial layer on a rigid base material layer, affixing a flexible base material layer to the silicon sacrificial layer by an adhesive layer, forming a display element layer on the flexible base material layer, and utilizing a fluorine-containing corrosive gas to etch and gasify the silicon sacrificial layer to cause the flexible base material layer to separate from the rigid base material layer.
The present invention further provides a substrate for manufacturing a flexible display. The substrate includes a rigid base material layer, a silicon sacrificial layer disposed on the rigid base material layer, an adhesive layer disposed on the silicon sacrificial layer, a flexible base material layer disposed on the adhesive layer, and a display element layer disposed on flexible base material layer. The silicon sacrificial layer is sandwiched between the rigid base material layer and the adhesive layer. The adhesive layer is sandwiched between the silicon sacrificial layer and the flexible base material layer. The flexible base material layer is sandwiched between the display element layer and the adhesive layer.
The present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:
The present invention will now be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only. It is not intended to be exhaustive or to be limited to the precise form disclosed.
Referring to
Referring to
Referring to
Referring to
Referring to
After the above-mentioned steps, the substrate 100 which can be thereafter used to manufacture a flexible display is finished. Referring to
Referring to
When xenon fluoride is selected as the fluorine-containing corrosive gas 160, a reaction apparatus is firstly provided and vacuumed to cause the reaction apparatus to have a vacuum pressure of less than 5 Torr, and then the xenon fluoride is filled into the reaction apparatus and used to etch the silicon sacrificial layer 120, wherein a pressure of the xenon fluoride in the reaction apparatus is less than 5 Torr. In the reaction apparatus filled with the xenon fluoride as the fluorine-containing corrosive gas, an isotropic chemical reaction is occurred between the silicon sacrificial layer 120 and the xenon fluoride, and the silicon sacrificial layer 120 is etched and gasified to turn into xenon gas and silicon tetrafluoride (SiF4) gas to be capable of removing out of the reaction apparatus. When the silicon sacrificial layer 120 is etched for a specified time until the xenon fluoride filled into the reaction apparatus is almost fully reacted with the silicon sacrificial layer 120 to turn into xenon gas and silicon tetrafluoride gas, the xenon gas and the silicon tetrafluoride gas are removed out of the reaction apparatus and a reaction cycle is finished. Thereafter, a new amount of xenon fluoride is filled into the reaction apparatus to carry out another reaction cycle. Based on different sizes and thicknesses of the silicon sacrificial layer 120, reaction cycles and an etching time for each reaction cycle may be different and can be easily determined according to practical requirement. For example, about 1 to 1000 reaction cycles can be used, and an etching time for each reaction cycle is about 1 to 180 seconds, until the silicon sacrificial layer 120 is fully reacted with the xenon fluoride. After a full reaction between the silicon sacrificial layer 120 and the xenon fluoride, the silicon sacrificial layer 120 is wholly and cleanly removed away, and the rigid base material layer 110 is thus automatically and completely peeled off from the flexible base material layer 140. In the course of the chemical reaction between the silicon sacrificial layer 120 and the xenon fluoride, the silicon sacrificial layer 120 is cleanly and completely removed away with no residue, and also no extraneous matter is incurred, to thereby effectively peel the rigid base material layer 110 off from the flexible base material layer 140. The chemical reaction between the xenon fluoride and the silicon sacrificial layer 120 nearly does not cause any damage to the flexible base material layer 140 and the display element layer 150, and thus the performance of the flexible base material layer 140 and the display element layer 150 is effectively not influenced after the rigid base material layer 110 is peeled off. In particular, in peeling off the rigid base material layer 110, the electrical properties of each element, such as, the thin film transistor control circuit, the conductive electrodes, the organic material functional layer and the metal electrodes, of the display element layer 150 are not affected, to thereby facilitate manufacturing of high-quality flexible displays by using the substrate 100.
It is mentioned that, if chlorine trifluoride (ClF3), bromine trifluoride (BrF3), or fluorine gas (F2) is used as the fluorine-containing corrosive gas 160, the reaction products between the silicon sacrificial layer 120 and the fluorine-containing corrosive gas 160 are still gases, for example, chlorine gas (or bromine gas) and silicon tetrafluoride (SiF4) gas, which are also capable of removing out of the reaction apparatus.
When chlorine trifluoride is selected as the fluorine-containing corrosive gas 160, a reaction apparatus is firstly provided and vacuumed to cause the reaction apparatus to have a vacuum pressure of less than 5 Torr, and then the chlorine trifluoride is filled into the reaction apparatus and used to etch the silicon sacrificial layer 120, wherein a pressure of the chlorine trifluoride in the reaction apparatus is less than 5 Torr. In the reaction apparatus filled with the chlorine trifluoride as the fluorine-containing corrosive gas, an isotropic chemical reaction is occurred between the silicon sacrificial layer 120 and the chlorine trifluoride, and the silicon sacrificial layer 120 is etched and gasified to turn into chlorine gas and silicon tetrafluoride (SiF4) gas to be capable of removing out of the reaction apparatus. When the silicon sacrificial layer 120 is etched for a specified time until the chlorine trifluoride filled into the reaction apparatus is almost fully reacted with the silicon sacrificial layer 120 to turn into chlorine gas and silicon tetrafluoride gas, the chlorine gas and the silicon tetrafluoride gas are removed out of the reaction apparatus and a reaction cycle is finished. Thereafter, a new amount of chlorine trifluoride is filled into the reaction apparatus to carry out another reaction cycle. Based on different sizes and thicknesses of the silicon sacrificial layer 120, reaction cycles and an etching time for each reaction cycle may be different and can be easily determined according to practical requirement. For example, about 1 to 1000 reaction cycles can be used, and an etching time for each reaction cycle is about 1 to 180 seconds, until the silicon sacrificial layer 120 is fully reacted with the chlorine trifluoride. After a full reaction between the silicon sacrificial layer 120 and the chlorine trifluoride, the silicon sacrificial layer 120 is wholly and cleanly removed away, and the rigid base material layer 110 is thus automatically and completely peeled off from the flexible base material layer 140.
When bromine trifluoride is selected as the fluorine-containing corrosive gas 160, a reaction apparatus is firstly provided and vacuumed to cause the reaction apparatus to have a vacuum pressure of less than 5 Torr, and then the bromine trifluoride is filled into the reaction apparatus and used to etch the silicon sacrificial layer 120, wherein a pressure of the bromine trifluoride in the reaction apparatus is less than 5 Torr. In the reaction apparatus filled with the bromine trifluoride as the fluorine-containing corrosive gas, an isotropic chemical reaction is occurred between the silicon sacrificial layer 120 and the bromine trifluoride, and the silicon sacrificial layer 120 is etched and gasified to turn into bromine gas and silicon tetrafluoride (SiF4) gas to be capable of removing out of the reaction apparatus. When the silicon sacrificial layer 120 is etched for a specified time until the bromine trifluoride filled into the reaction apparatus is almost fully reacted with the silicon sacrificial layer 120 to turn into bromine gas and silicon tetrafluoride gas, the bromine gas and the silicon tetrafluoride gas are removed out of the reaction apparatus and a reaction cycle is finished. Thereafter, a new amount of bromine trifluoride is filled into the reaction apparatus to carry out another reaction cycle. Based on different sizes and thicknesses of the silicon sacrificial layer 120, reaction cycles and an etching time for each reaction cycle may be different and can be easily determined according to practical requirement. For example, about 1 to 1000 reaction cycles can be used, and an etching time for each reaction cycle is about 1 to 180 seconds, until the silicon sacrificial layer 120 is fully reacted with the bromine trifluoride. After a full reaction between the silicon sacrificial layer 120 and the bromine trifluoride, the silicon sacrificial layer 120 is wholly and cleanly removed away, and the rigid base material layer 110 is thus automatically and completely peeled off from the flexible base material layer 140.
When fluorine gas is selected as the fluorine-containing corrosive gas 160, a reaction apparatus is firstly provided and vacuumed to cause the reaction apparatus to have a vacuum pressure of less than 5 Torr, and then the fluorine gas is filled into the reaction apparatus and used to etch the silicon sacrificial layer 120, wherein a pressure of the fluorine gas in the reaction apparatus is less than 5 Torr. In the reaction apparatus filled with the fluorine gas as the fluorine-containing corrosive gas, an isotropic chemical reaction is occurred between the silicon sacrificial layer 120 and the fluorine gas, and the silicon sacrificial layer 120 is etched and gasified to turn into silicon tetrafluoride (SiF4) gas to be capable of removing out of the reaction apparatus. When the silicon sacrificial layer 120 is etched for a specified time until the fluorine gas filled into the reaction apparatus is almost fully reacted with the silicon sacrificial layer 120 to turn into silicon tetrafluoride gas, the silicon tetrafluoride gas is removed out of the reaction apparatus and a reaction cycle is finished. Thereafter, a new amount of fluorine gas is filled into the reaction apparatus to carry out another reaction cycle. Based on different sizes and thicknesses of the silicon sacrificial layer 120, reaction cycles and an etching time for each reaction cycle may be different and can be easily determined according to practical requirement. For example, about 1 to 1000 reaction cycles can be used, and an etching time for each reaction cycle is about 1 to 180 seconds, until the silicon sacrificial layer 120 is fully reacted with the fluorine gas. After a full reaction between the silicon sacrificial layer 120 and the fluorine gas, the silicon sacrificial layer 120 is wholly and cleanly removed away, and the rigid base material layer 110 is thus automatically and completely peeled off from the flexible base material layer 140.
Referring to
The method of the first embodiment is mainly used for manufacturing a single flexible display, for example, an FOLED display. In addition, the method is also applicable to simultaneously manufacture a plurality of flexible displays. In this situation, the substrate obtained by the method of the first embodiment will have a large area and can be used to manufacture a plurality of flexible displays. The following is described in detail based on a second embodiment of the present invention.
Specifically, referring to
In this embodiment, after the display element layer 250 is formed and before the rigid base material layer 210 is peeled off, a cutting step is required by using a cutting device (not shown) to cut the substrate 200 into plurality of independent FOLED panel units 201 along the cut lines 205 (the dashed line in
It should be mentioned that, in the method of the first embodiment, the substrate 100 can also be carried out by a cutting step in order to accelerating the peeling speed of the rigid base material layer 110. For example, the substrate 100 can be cut around the peripheral edges thereof to expose the peripheral side surfaces of the silicon sacrificial layer 120, so that the fluorine-containing corrosive gas 160 can react rapidly starting from the peripheral side surfaces of the silicon sacrificial layer 120, to thereby accelerate the peeling speed of the rigid base material layer 110.
In summary, the method of manufacturing a flexible display uses fluorine-containing corrosive gas to react with the silicon sacrificial layer, so that the rigid base material layer is peeled off automatically and cleanly due to a gasification of the silicon sacrificial layer. Furthermore, the chemical reaction between of the fluorine-containing corrosive gas and the silicon sacrificial layer nearly does not cause any damage to the flexible base material layer and the display element layer, to thereby avoid causing adverse impact to the performance of the flexible base material layer and the display element layer in the course of peeling off the rigid base material layer. That is, the method of manufacturing a flexible display does not affect the electrical properties of elements, such as, the thin film transistor array and the organic material functional layer, of the display element layer in peeling off the rigid base material layer, thereby facilitating to produce high-quality flexible displays. Moreover, since a certain amount of stress is possibly existed between the flexible base material layer and the display element layer disposed on the flexible base material layer, a peripheral region of the substrate will become warped when the rigid base material layer is peeled off. It is preferably to accelerate the isotropic chemical reaction between the fluorine-containing corrosive gas and the silicon sacrificial layer to thereby accelerate the peeling speed of the rigid base material layer.
In addition, the method of manufacturing a flexible display is also applicable to manufacture a plurality of flexible displays, simultaneously. In this situation, the substrate made by the method will have a large area. After the display element layer is formed and before the rigid base material layer is peeled off, a cutting step is utilized to cut the substrate into a plurality of FOLED panel units. As a result, the plurality of FOLED panel units are separated from each other, and the peripheral side surfaces of the silicon sacrificial layer are exposed, so that the fluorine-containing corrosive gas can react with the silicon sacrificial layer rapidly starting from the peripheral side surfaces of the silicon sacrificial layer, thereby accelerating the peeling speed of the rigid base material layer.
While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.
Number | Date | Country | Kind |
---|---|---|---|
201210232494.7 | Jul 2012 | CN | national |