WO2018223391A1 - Micro-led array transfer method, manufacturing method and display device - Google Patents

Micro-led array transfer method, manufacturing method and display device Download PDF

Info

Publication number
WO2018223391A1
WO2018223391A1 PCT/CN2017/087774 CN2017087774W WO2018223391A1 WO 2018223391 A1 WO2018223391 A1 WO 2018223391A1 CN 2017087774 W CN2017087774 W CN 2017087774W WO 2018223391 A1 WO2018223391 A1 WO 2018223391A1
Authority
WO
WIPO (PCT)
Prior art keywords
micro
substrate
led array
underfill
display device
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2017/087774
Other languages
French (fr)
Inventor
Quanbo Zou
Peixuan CHEN
Xiangxu FENG
Tao GAN
Xiaoyang Zhang
Zhe Wang
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Goertek Inc
Original Assignee
Goertek Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Goertek Inc filed Critical Goertek Inc
Priority to CN201780002375.3A priority Critical patent/CN109496351B/en
Priority to PCT/CN2017/087774 priority patent/WO2018223391A1/en
Priority to US16/620,224 priority patent/US11024611B1/en
Publication of WO2018223391A1 publication Critical patent/WO2018223391A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D86/00—Integrated devices formed in or on insulating or conducting substrates, e.g. formed in silicon-on-insulator [SOI] substrates or on stainless steel or glass substrates
    • H10D86/01—Manufacture or treatment
    • H10D86/021—Manufacture or treatment of multiple TFTs
    • H10D86/0214—Manufacture or treatment of multiple TFTs using temporary substrates
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/01—Manufacture or treatment
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/80—Constructional details
    • H10H20/85—Packages
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/04—Apparatus for manufacture or treatment
    • H10P72/0446—Apparatus for mounting on conductive members, e.g. leadframes or conductors on insulating substrates
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/30—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations
    • H10P72/32—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations between different workstations
    • H10P72/3206—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations between different workstations the substrate being handled substantially vertically
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/30—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations
    • H10P72/32—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations between different workstations
    • H10P72/3212—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations between different workstations the substrates to be conveyed not being semiconductor wafers or large planar substrates, e.g. chips or lead frames
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/01—Manufacture or treatment
    • H10H20/011—Manufacture or treatment of bodies, e.g. forming semiconductor layers
    • H10H20/018—Bonding of wafers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/01—Manufacture or treatment
    • H10H20/036—Manufacture or treatment of packages
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
    • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
    • H10H20/01—Manufacture or treatment
    • H10H20/036—Manufacture or treatment of packages
    • H10H20/0364—Manufacture or treatment of packages of interconnections
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K71/00—Manufacture or treatment specially adapted for the organic devices covered by this subclass
    • H10K71/80—Manufacture or treatment specially adapted for the organic devices covered by this subclass using temporary substrates
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/70—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping
    • H10P72/74—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/70—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping
    • H10P72/74—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support
    • H10P72/7432—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/70—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping
    • H10P72/74—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support
    • H10P72/7434—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/70—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping
    • H10P72/74—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support
    • H10P72/744—Details of chemical or physical process used for separating the auxiliary support from a device or a wafer
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/70—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping
    • H10P72/74—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for supporting or gripping using temporarily an auxiliary support
    • H10P72/744—Details of chemical or physical process used for separating the auxiliary support from a device or a wafer
    • H10P72/7442—Separation by peeling
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
    • H10W72/00—Interconnections or connectors in packages
    • H10W72/01—Manufacture or treatment
    • H10W72/0198—Manufacture or treatment batch processes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
    • H10W72/00—Interconnections or connectors in packages
    • H10W72/071—Connecting or disconnecting
    • H10W72/072—Connecting or disconnecting of bump connectors
    • H10W72/07202—Connecting or disconnecting of bump connectors using auxiliary members
    • H10W72/07204—Connecting or disconnecting of bump connectors using auxiliary members using temporary auxiliary members, e.g. sacrificial coatings
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
    • H10W90/00—Package configurations

Definitions

  • the present invention relates to a method for transferring a micro-LED array, a method for manufacturing a display device and a display device.
  • the micro-LED technology refers to the LED array of small size integrated on a substrate with high density.
  • the micro-LED technology is starting development, and it is expected in the industry that a high-quality micro-LED product comes into the market.
  • High-quality micro-LED will have a deep affection on the conventional display products such as LCD/OLED that have already been put into the market.
  • a micro-LED array is first formed on a growth substrate. Then, the micro-LED array is transferred to a receiving substrate, or is transferred to a receiving substrate via a carrier substrate.
  • the receiving substrate is a display screen, for example.
  • the micro-LED array can be transferred from one substrate to another substrate through laser lifting-off (LLO) .
  • LLO laser lifting-off
  • Fig. 1 shows a prior art example of transferring a micro-LED array from a first substrate 101 (acarrier substrate or a growth substrate) to a receiving substrate 102.
  • the micro-LED array 104 is formed on the first substrate 101.
  • the micro-LED array 104 is bonded onto the receiving substrate 102.
  • the micro-LED array 104 is bonded onto the anode 106 on top of a TFT (Thin Film Transistor) circuitry 103 formed in the receiving substrate 102through solder bond 105.
  • the first substrate 101 is laser-transparent. Laser 107 is irradiated from the side of the first substrate 101 onto the micro-LED array 104 to lift-off it.
  • the micro-LEDs in the micro-LED array are of a very small size, the bonding strength between the micro-LEDs and the receiving substrate is very low. Especially, when the resolution of the display device is improved and the micro-LEDs are getting smaller and smaller, the yield loss during transfer is increased.
  • the bonding strength can be improved when the bonding temperature is elevated.
  • the elevated bonding temperature will significantly degrade the bonding quality due to thermal mismatch of the micro-LEDs and the receiving substrate.
  • lowered bonding temperature is preferred, especially, for a micro-LED transfer with a large area, where the bonding strength will be a key concern.
  • One object of this invention is to provide a new technical solution for transferring a micro-LED array.
  • a method for transferring a micro-LED array comprising: bonding the micro-LED array on a first substrate onto a receiving substrate through micro-bumps, wherein the first substrate is laser transparent; applying underfill into a gap between the first substrate and the receiving substrate; irradiating laser onto the micro-LED array from a side of the first substrate to lift-off the micro-LED array from the first substrate; and removing the underfill.
  • the method further comprises: separating the first substrate from the receiving substrate.
  • the first substrate is a sapphire substrate.
  • the micro-bumps are of low temperature bonding material.
  • the underfill is at least one of is a low viscosity liquid, solvent, resist, glue, polymer, silicone and grease.
  • the underfill is solidified or the viscosity of the underfill is increased during the micro-LED array is lifted-off.
  • the underfill is applied in a low atmospheric pressure environment or in vacuum.
  • the underfill is removed by chemical, solvent, undercutting or phase change.
  • a second aspect of the present invention there is provided method for manufacturing a display device, comprising transferring a micro-LED array from a first substrate to a receiving substrate of the display device by using the method for transferring a micro-LED array according to an embodiment.
  • display device manufactured by using the method for manufacturing a display device according to an embodiment.
  • the bonding strength may be improved during a transfer of a micro-LED array.
  • Fig. 1 shows a schematic diagram of a prior art example of transferring a micro-LED array through laser lifting-off.
  • Figs. 2-5 shows a schematic diagram of a process of transferring a micro-LED array from a first substrate to a receiving substrate according to an embodiment.
  • an underfill during a LLO transfer of a micro-LED array to improve the bonding strength between the micro-LED array.
  • the underfill can be removed after the transfer.
  • Figs. 2-5 shows a schematic diagram of a process of transferring a micro-LED array from a first substrate to a receiving substrate according to an embodiment.
  • the micro-LED array 204 on a first substrate 201 is bonded onto a receiving substrate 202 through micro-bumps 206.
  • the first substrate 201 is laser transparent. For example, it is a sapphire substrate.
  • the micro bumps 206 may be anodes on top of the circuitry 203 such as a TFT circuitry in the receiving substrate 202.
  • the micro-LEDs 204 are bonded on the micro-bumps 206 through solder 205.
  • the micro-bumps 206 are of low temperature bonding material, such as In, Sn or other low temperature metals/alloys. It can also be electrical conductive adhesives or resists.
  • underfill 208 is applied into a gap between the first substrate 201 and the receiving substrate 202.
  • the underfill is applied by capillary.
  • the underfill can act as a protection layer for the micro-LEDs 204 and the receiving substrate 202 during the laser lifting-off.
  • the underfill 208 can be at least one of is a low viscosity liquid, solvent, resist, glue, polymer, silicone and grease.
  • the underfill 208 is applied in a low atmospheric pressure environment or in vacuum. In this way, the bubbles or air in the underfill can be gotten rid of.
  • laser 207 is irradiated onto the micro-LED array from a side of the first substrate to lift-off the micro-LED array from the first substrate.
  • the laser 207 is irradiated onto selected micro-LEDs 204.
  • the selected micro-LEDs constitute the micro-LED array 204 which is to be transferred to the receiving substrate 202.
  • the underfill is applied in an elevated temperature.
  • the elevated temperature is not as high as that causing a significant thermal mismatch. Then, the underfill is solidified or the viscosity of the underfill is increased during the micro-LED array is lifted-off.
  • the underfill will not be solidified or the viscosity thereof will not be increased. This will simplify the processing.
  • a temporary underfill 208 is added into gap between the first substrate 201 and the receiving substrate 202.
  • the underfill will mechanically enhance the bonding between the two substrates.
  • the yield will significantly be improved LLO yield.
  • the underfill can also function as a protection layer for the receiving substrate during the laser lifting-off. For example, it prevents the laser from irradiating onto the receiving substrate 202, which may damage the circuitry 203 in the receiving substrate 202.
  • the underfill will reinforce the bonding strength between the micro-LEDs and the receiving substrate, without a high temperature/high strength bonding. This will reduce the negative influence caused by a thermal mismatch between the micro-LEDs and the receiving substrate.
  • the underfill can be low viscosity resist, polymer, silicone, glue or grease, orit can even be liquid, such as water, solvent.
  • the underfill can be applied into the gap by capillary force due to surface tension.
  • the underfill 208 is removed.
  • the underfill is removed by chemical, solvent, undercutting or phase change. Then, it is rinsed and dried.
  • the first substrate 201 is separated from the receiving substrate 202.
  • an embodiment in another embodiment, includes a method for manufacturing a display device.
  • the manufacturing method comprises transferring a micro-LED array from a first substrate to a receiving substrate of the display device by using the method for transferring a micro-LED array according to an embodiment as above.
  • the display device can be a display panel, a display screen and so on.
  • another embodiment includes a display device manufactured by using the method for manufacturing a display device according to an embodiment as above.
  • the display device will show a better performance than one of the prior art under a similar condition.
  • another embodiment can further include an electronic apparatus.
  • the electronic apparatus contains a display device as above.
  • the electronic apparatus can be a mobile phone, a pad computer and so on.

Landscapes

  • Led Device Packages (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

A micro-LED transfer method, manufacturing method and display device are provided. The micro-LED transfer method comprises: bonding the micro-LED array (204) on a first substrate (201) onto a receiving substrate (202) through micro-bumps (206), wherein the first substrate (201) is laser transparent; applying underfill (208) into a gap between the first substrate (201) and the receiving substrate (202); irradiating laser (207) onto the micro-LED array (204) from a side of the first substrate (201) to lift-off the micro-LED array (204) from the first substrate (201); and removing the underfill (208). The bonding strength may be improved during a transfer of a micro-LED array (204).

Description

MICRO-LED ARRAY TRANSFER METHOD, MANUFACTURING METHOD AND DISPLAY DEVICE FIELD OF THE INVENTION
The present invention relates to a method for transferring a micro-LED array, a method for manufacturing a display device and a display device.
BACKGROUND OF THE INVENTION
The micro-LED technology refers to the LED array of small size integrated on a substrate with high density. Currently, the micro-LED technology is starting development, and it is expected in the industry that a high-quality micro-LED product comes into the market. High-quality micro-LED will have a deep affection on the conventional display products such as LCD/OLED that have already been put into the market.
In the process of manufacturing micro-LEDs, a micro-LED array is first formed on a growth substrate. Then, the micro-LED array is transferred to a receiving substrate, or is transferred to a receiving substrate via a carrier substrate. The receiving substrate is a display screen, for example.
In the prior art, the micro-LED array can be transferred from one substrate to another substrate through laser lifting-off (LLO) .
Fig. 1 shows a prior art example of transferring a micro-LED array from a first substrate 101 (acarrier substrate or a growth substrate) to a receiving substrate 102. As shown in Fig. 1, the micro-LED array 104 is formed on the first substrate 101. The micro-LED array 104 is bonded onto the receiving substrate 102. For example, the micro-LED array 104 is bonded onto the anode 106 on top of a TFT (Thin Film Transistor) circuitry 103 formed in the receiving substrate 102through solder bond 105. The first substrate 101 is laser-transparent. Laser 107 is irradiated from the side of the first substrate 101 onto the micro-LED array 104 to lift-off it.
Since the micro-LEDs in the micro-LED array are of a very small size, the bonding strength between the micro-LEDs and the receiving substrate is very low. Especially, when the resolution of the display device is improved and the micro-LEDs are getting smaller and smaller,  the yield loss during transfer is increased.
The bonding strength can be improved when the bonding temperature is elevated. However, the elevated bonding temperature will significantly degrade the bonding quality due to thermal mismatch of the micro-LEDs and the receiving substrate. In this regard, lowered bonding temperature is preferred, especially, for a micro-LED transfer with a large area, where the bonding strength will be a key concern.
Therefore, there is a demand in the art that a new solution for transferring a micro-LED array shall be proposed to address at least one of the problems in the prior art.
SUMMARY OF THE INVENTION
One object of this invention is to provide a new technical solution for transferring a micro-LED array.
According to a first aspect of the present invention, there is provided a method for transferring a micro-LED array, comprising: bonding the micro-LED array on a first substrate onto a receiving substrate through micro-bumps, wherein the first substrate is laser transparent； applying underfill into a gap between the first substrate and the receiving substrate； irradiating laser onto the micro-LED array from a side of the first substrate to lift-off the micro-LED array from the first substrate； and removing the underfill.
Alternatively or optionally, the method further comprises: separating the first substrate from the receiving substrate.
Alternatively or optionally, the first substrate is a sapphire substrate.
Alternatively or optionally, the micro-bumps are of low temperature bonding material.
Alternatively or optionally, the underfill is at least one of is a low viscosity liquid, solvent, resist, glue, polymer, silicone and grease.
Alternatively or optionally, the underfill is solidified or the viscosity of the underfill is increased during the micro-LED array is lifted-off.
Alternatively or optionally, the underfill is applied in a low atmospheric pressure environment or in vacuum.
Alternatively or optionally, the underfill is removed by chemical, solvent, undercutting  or phase change.
According to a second aspect of the present invention, there is provided method for manufacturing a display device, comprising transferring a micro-LED array from a first substrate to a receiving substrate of the display device by using the method for transferring a micro-LED array according to an embodiment.
According to a third aspect of the present invention, there is provided display device manufactured by using the method for manufacturing a display device according to an embodiment.
According to an embodiment, the bonding strength may be improved during a transfer of a micro-LED array.
Further features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments according to the present invention with reference to the attached drawings.
BRIEF DISCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description thereof, serve to explain the principles of the invention.
Fig. 1 shows a schematic diagram of a prior art example of transferring a micro-LED array through laser lifting-off.
Figs. 2-5 shows a schematic diagram of a process of transferring a micro-LED array from a first substrate to a receiving substrate according to an embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Various exemplary embodiments of the present invention will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated  otherwise.
The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.
Techniques, methods and apparatus as known by one of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.
In all of the examples illustrated and discussed herein, any specific values should be interpreted to be illustrative only and non-limiting. Thus, other examples of the exemplary embodiments could have different values.
Notice that similar reference numerals and letters refer to similar items in the following figures, and thus once an item is defined in one figure, it is possible that it need not be further discussed for following figures.
In an embodiment, it is proposed to apply an underfill during a LLO transfer of a micro-LED array to improve the bonding strength between the micro-LED array. The underfill can be removed after the transfer.
Figs. 2-5 shows a schematic diagram of a process of transferring a micro-LED array from a first substrate to a receiving substrate according to an embodiment.
As shown in Fig. 2, the micro-LED array 204 on a first substrate 201 is bonded onto a receiving substrate 202 through micro-bumps 206. The first substrate 201 is laser transparent. For example, it is a sapphire substrate.
The micro bumps 206 may be anodes on top of the circuitry 203 such as a TFT circuitry in the receiving substrate 202. For example, the micro-LEDs 204 are bonded on the micro-bumps 206 through solder 205.
For example, the micro-bumps 206 are of low temperature bonding material, such as In, Sn or other low temperature metals/alloys. It can also be electrical conductive adhesives or resists.
As shown in Fig. 3, underfill 208 is applied into a gap between the first substrate 201 and the receiving substrate 202. For example, the underfill is applied by capillary. The underfill can act as a protection layer for the micro-LEDs 204 and the receiving substrate 202 during the  laser lifting-off.
For example, the underfill 208 can be at least one of is a low viscosity liquid, solvent, resist, glue, polymer, silicone and grease.
In an example, the underfill 208 is applied in a low atmospheric pressure environment or in vacuum. In this way, the bubbles or air in the underfill can be gotten rid of.
As shown in Fig. 4, laser 207 is irradiated onto the micro-LED array from a side of the first substrate to lift-off the micro-LED array from the first substrate.
In Fig. 4, the laser 207 is irradiated onto selected micro-LEDs 204. The selected micro-LEDs constitute the micro-LED array 204 which is to be transferred to the receiving substrate 202.
In an example, the underfill is applied in an elevated temperature. The elevated temperature is not as high as that causing a significant thermal mismatch. Then, the underfill is solidified or the viscosity of the underfill is increased during the micro-LED array is lifted-off.
Alternativley, the underfill will not be solidified or the viscosity thereof will not be increased. This will simplify the processing.
Here, a temporary underfill 208 is added into gap between the first substrate 201 and the receiving substrate 202. The underfill will mechanically enhance the bonding between the two substrates. Thus, the yield will significantly be improved LLO yield.
In addition, the underfill can also function as a protection layer for the receiving substrate during the laser lifting-off. For example, it prevents the laser from irradiating onto the receiving substrate 202, which may damage the circuitry 203 in the receiving substrate 202.
Here, the underfill will reinforce the bonding strength between the micro-LEDs and the receiving substrate, without a high temperature/high strength bonding. This will reduce the negative influence caused by a thermal mismatch between the micro-LEDs and the receiving substrate.
The underfill can be low viscosity resist, polymer, silicone, glue or grease, orit can even be liquid, such as water, solvent. The underfill can be applied into the gap by capillary force due to surface tension.
As shown in Fig. 5, the underfill 208 is removed. For example the underfill is removed  by chemical, solvent, undercutting or phase change. Then, it is rinsed and dried.
Next, the first substrate 201 is separated from the receiving substrate 202.
In another embodiment, an embodiment includes a method for manufacturing a display device. The manufacturing method comprises transferring a micro-LED array from a first substrate to a receiving substrate of the display device by using the method for transferring a micro-LED array according to an embodiment as above. The display device can be a display panel, a display screen and so on.
In another embodiment, another embodiment includes a display device manufactured by using the method for manufacturing a display device according to an embodiment as above.
In comparison with the prior art, since the underfill can improve the bonding strength during the laser lifting-off and/or can be a protection layer for the receiving substrate, the display device will show a better performance than one of the prior art under a similar condition.
In another embodiment, another embodiment can further include an electronic apparatus. The electronic apparatus contains a display device as above. For example, the electronic apparatus can be a mobile phone, a pad computer and so on.
Although some specific embodiments of the present invention have been demonstrated in detail with examples, it should be understood by a person skilled in the art that the above examples are only intended to be illustrative but not to limit the scope of the present invention.

Claims (10)

  1. A method for transferring a micro-LED array, comprising:
    bonding the micro-LED array on a first substrate onto a receiving substrate through micro-bumps, wherein the first substrate is laser transparent；
    applying underfill into a gap between the first substrate and the receiving substrate；
    irradiating laser onto the micro-LED array from a side of the first substrate to lift-off the micro-LED array from the first substrate； and
    removing the underfill.
  2. The method according to claim 1, further comprising:
    separating the first substrate from the receiving substrate.
  3. The method according to claim 1 or 2, wherein the first substrate is a sapphire substrate.
  4. The method according to any of claims 1-3, wherein the micro-bumps are of low temperature bonding material.
  5. The method according to any of claims 1-4, wherein the underfill is at least one of is a low viscosity liquid, solvent, resist, glue, polymer, silicone and grease.
  6. The method according to any of claims 1-5, wherein the underfill is solidified or the viscosity of the underfill is increased during the micro-LED array is lifted-off.
  7. The method according to any of claims 1-6, wherein the underfill is applied in a low atmospheric pressure environment or in vacuum.
  8. The method according to any of claims 1-7, wherein the underfill is removed by chemical, solvent, undercutting or phase change.
  9. A method for manufacturing a display device, comprising transferring a micro-LED array from a first substrate to a receiving substrate of the display device by using the method for transferring a micro-LED array according to any of claims 1-8.
  10. A display device manufactured by using the method for manufacturing a display device according to claim 9.
PCT/CN2017/087774 2017-06-09 2017-06-09 Micro-led array transfer method, manufacturing method and display device Ceased WO2018223391A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN201780002375.3A CN109496351B (en) 2017-06-09 2017-06-09 Micro-LED array transfer method, manufacturing method, and display device
PCT/CN2017/087774 WO2018223391A1 (en) 2017-06-09 2017-06-09 Micro-led array transfer method, manufacturing method and display device
US16/620,224 US11024611B1 (en) 2017-06-09 2017-06-09 Micro-LED array transfer method, manufacturing method and display device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2017/087774 WO2018223391A1 (en) 2017-06-09 2017-06-09 Micro-led array transfer method, manufacturing method and display device

Publications (1)

Publication Number Publication Date
WO2018223391A1 true WO2018223391A1 (en) 2018-12-13

Family

ID=64565662

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/087774 Ceased WO2018223391A1 (en) 2017-06-09 2017-06-09 Micro-led array transfer method, manufacturing method and display device

Country Status (3)

Country Link
US (1) US11024611B1 (en)
CN (1) CN109496351B (en)
WO (1) WO2018223391A1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020096144A (en) * 2018-12-14 2020-06-18 Tdk株式会社 Element array manufacturing method and specific element removing method
WO2021101650A1 (en) * 2019-11-18 2021-05-27 Facebook Technologies, Llc Bonding of light emitting diode arrays
CN112967961A (en) * 2020-05-28 2021-06-15 重庆康佳光电技术研究院有限公司 A transfer method and device
US11056611B2 (en) 2018-09-11 2021-07-06 Facebook Technologies, Llc Mesa formation for wafer-to-wafer bonding
US11145786B2 (en) 2018-09-11 2021-10-12 Facebook Technologies, Llc Methods for wafer-to-wafer bonding
WO2021236382A1 (en) * 2020-05-18 2021-11-25 Nanosys, Inc. Subpixel light emitting diodes for direct view display and methods of making the same
KR20210153732A (en) * 2019-06-17 2021-12-17 청두 비스타 옵토일렉트로닉스 씨오., 엘티디. Display device, display panel and manufacturing method thereof
US11342479B2 (en) 2018-09-11 2022-05-24 Facebook Technologies, Llc Reducing bowing of materials before wafer-to-wafer bonding for LED manufacturing

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11227970B1 (en) * 2018-10-18 2022-01-18 Facebook Technologies, Llc Light emitting diodes manufacture and assembly
DE102018132824B4 (en) * 2018-12-19 2024-10-10 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung METHOD FOR PRODUCING AN OPTOELECTRONIC LIGHTING DEVICE
CN110265348B (en) * 2019-06-17 2021-07-20 上海天马微电子有限公司 A transport substrate, a transport method for light-emitting diodes, and transport equipment
CN112186091B (en) * 2019-06-17 2022-04-15 成都辰显光电有限公司 Bonding method of micro light-emitting diode chip
US12125830B2 (en) * 2019-07-01 2024-10-22 Lg Electronics Inc. Display device using micro LED, and manufacturing method therefor
CN112310115B (en) * 2019-07-26 2023-06-06 京东方科技集团股份有限公司 A driving backplane, a display panel and a display device
CN110444547A (en) * 2019-07-29 2019-11-12 南京中电熊猫平板显示科技有限公司 A micro light-emitting diode array display backplane and its manufacturing method
CN110690244B (en) * 2019-10-15 2021-11-05 京东方科技集团股份有限公司 A kind of backplane, display panel and transfer method of micro light emitting diode
CN112820752B (en) * 2019-11-15 2023-01-03 云谷（固安）科技有限公司 Micro light-emitting diode array substrate and transfer method of micro light-emitting diode
WO2021097734A1 (en) * 2019-11-21 2021-05-27 重庆康佳光电技术研究院有限公司 Method for transferring led chip
CN112992754B (en) * 2020-05-22 2022-02-25 重庆康佳光电技术研究院有限公司 A mass transfer device and transfer method thereof
CN113284991A (en) * 2021-07-09 2021-08-20 苏州芯聚半导体有限公司 Micro LED chip, packaging method thereof and electronic device
JP7455789B2 (en) * 2021-10-08 2024-03-26 東レエンジニアリング株式会社 Chip removal method and device
WO2023163944A1 (en) * 2022-02-22 2023-08-31 Nanosys, Inc. Apparatus and method for transferring light-emitting diodes
CN115440624A (en) * 2022-08-12 2022-12-06 北京石油化工学院 A kind of pneumatic mass transfer device and method based on microwell array
CN121844733A (en) * 2023-09-15 2026-04-10 应用材料公司 Selective mass transfer based on temporary underfill for micro-LED fabrication
KR102868339B1 (en) * 2023-12-20 2025-10-14 한국광기술원 Micro LED display panel using direct panel transfer method without rearrangement process of micro LED chips and manufacturing method thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101488544A (en) * 2008-01-18 2009-07-22 晶元光电股份有限公司 Light emitting element and method for manufacturing the same
CN101996892A (en) * 2009-08-17 2011-03-30 晶元光电股份有限公司 System-level optoelectronic structure and fabrication method thereof
US20140159066A1 (en) * 2012-12-11 2014-06-12 LuxVue Technology Corporation Stabilization structure including sacrificial release layer and staging bollards
CN105036066A (en) * 2015-07-14 2015-11-11 华进半导体封装先导技术研发中心有限公司 Surface treatment method for protective cover of wafer level package
CN105493297A (en) * 2015-05-21 2016-04-13 歌尔声学股份有限公司 Transfer method, manufacturing method, device and electronic equipment of micro light emitting diode
CN106058010A (en) * 2016-07-26 2016-10-26 深圳市华星光电技术有限公司 Micro light emitting diode array's transfer printing method

Family Cites Families (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1706893A2 (en) * 2003-12-24 2006-10-04 Gelcore LLC Laser lift-off of sapphire from a nitride flip-chip
US7256483B2 (en) * 2004-10-28 2007-08-14 Philips Lumileds Lighting Company, Llc Package-integrated thin film LED
US7736945B2 (en) * 2005-06-09 2010-06-15 Philips Lumileds Lighting Company, Llc LED assembly having maximum metal support for laser lift-off of growth substrate
US7867793B2 (en) * 2007-07-09 2011-01-11 Koninklijke Philips Electronics N.V. Substrate removal during LED formation
US20090050921A1 (en) * 2007-08-23 2009-02-26 Philips Lumileds Lighting Company Llc Light Emitting Diode Array
US7687810B2 (en) * 2007-10-22 2010-03-30 Philips Lumileds Lighting Company, Llc Robust LED structure for substrate lift-off
US7928448B2 (en) * 2007-12-04 2011-04-19 Philips Lumileds Lighting Company, Llc III-nitride light emitting device including porous semiconductor layer
US20090230409A1 (en) * 2008-03-17 2009-09-17 Philips Lumileds Lighting Company, Llc Underfill process for flip-chip leds
US10147843B2 (en) * 2008-07-24 2018-12-04 Lumileds Llc Semiconductor light emitting device including a window layer and a light-directing structure
US7875984B2 (en) * 2009-03-04 2011-01-25 Koninklijke Philips Electronics N.V. Complaint bonding structures for semiconductor devices
US7977132B2 (en) * 2009-05-06 2011-07-12 Koninklijke Philips Electronics N.V. Extension of contact pads to the die edge via electrical isolation
US8089091B2 (en) * 2009-06-18 2012-01-03 Koninklijke Philips Electronics N.V. Semiconductor light emitting device with a contact formed on a textured surface
US8431423B2 (en) * 2009-07-16 2013-04-30 Koninklijke Philips Electronics N.V. Reflective substrate for LEDS
US20110018013A1 (en) * 2009-07-21 2011-01-27 Koninklijke Philips Electronics N.V. Thin-film flip-chip series connected leds
US8581349B1 (en) * 2011-05-02 2013-11-12 Monolithic 3D Inc. 3D memory semiconductor device and structure
US8476145B2 (en) * 2010-10-13 2013-07-02 Monolithic 3D Inc. Method of fabricating a semiconductor device and structure
US8536023B2 (en) * 2010-11-22 2013-09-17 Monolithic 3D Inc. Method of manufacturing a semiconductor device and structure
US8471280B2 (en) * 2009-11-06 2013-06-25 Koninklijke Philips Electronics N.V. Silicone based reflective underfill and thermal coupler
JP5017399B2 (en) * 2010-03-09 2012-09-05 株式会社東芝 Semiconductor light emitting device and method for manufacturing semiconductor light emitting device
US8642416B2 (en) * 2010-07-30 2014-02-04 Monolithic 3D Inc. Method of forming three dimensional integrated circuit devices using layer transfer technique
US9219005B2 (en) * 2011-06-28 2015-12-22 Monolithic 3D Inc. Semiconductor system and device
WO2012016377A1 (en) * 2010-08-03 2012-02-09 Industrial Technology Research Institute Light emitting diode chip, light emitting diode package structure, and method for forming the same
US8273610B2 (en) * 2010-11-18 2012-09-25 Monolithic 3D Inc. Method of constructing a semiconductor device and structure
US8912049B2 (en) * 2010-10-12 2014-12-16 Koninklijke Philips N.V. PEC biasing technique for LEDs
KR101932996B1 (en) * 2011-05-24 2018-12-27 루미리즈 홀딩 비.브이. P-n separation metal fill for flip chip leds
US9029173B2 (en) * 2011-10-18 2015-05-12 Monolithic 3D Inc. Method for fabrication of a semiconductor device and structure
US8896010B2 (en) * 2012-01-24 2014-11-25 Cooledge Lighting Inc. Wafer-level flip chip device packages and related methods
US8877561B2 (en) * 2012-06-07 2014-11-04 Cooledge Lighting Inc. Methods of fabricating wafer-level flip chip device packages
KR101539591B1 (en) * 2013-12-23 2015-07-28 광주과학기술원 Method of transferring light emitting diode using laser blocking layer
US9542638B2 (en) * 2014-02-18 2017-01-10 Apple Inc. RFID tag and micro chip integration design
US9698134B2 (en) * 2014-11-27 2017-07-04 Sct Technology, Ltd. Method for manufacturing a light emitted diode display
US10600823B2 (en) * 2015-09-02 2020-03-24 Facebook Technologies, Llc Assembly of semiconductor devices
CN107464859A (en) * 2016-06-03 2017-12-12 光宝光电(常州)有限公司 Light emitting diode construction, component and its manufacture method
US10389331B2 (en) * 2017-03-24 2019-08-20 Zhuhai Crystal Resonance Technologies Co., Ltd. Single crystal piezoelectric RF resonators and filters
US10439581B2 (en) * 2017-03-24 2019-10-08 Zhuhai Crystal Resonance Technologies Co., Ltd. Method for fabricating RF resonators and filters
US10141912B2 (en) * 2017-03-24 2018-11-27 Zhuhai Crystal Resonance Technologies Co., Ltd. RF resonators and filters
US10466572B2 (en) * 2017-03-24 2019-11-05 Zhuhai Crystal Resonance Technologies Co., Ltd. Method of fabrication for single crystal piezoelectric RF resonators and filters
US10984702B2 (en) * 2018-06-22 2021-04-20 Epistar Corporation Display apparatus with array of light emitting diodes and method of manufacturing the same
US10964867B2 (en) * 2018-10-08 2021-03-30 Facebook Technologies, Llc Using underfill or flux to promote placing and parallel bonding of light emitting diodes

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101488544A (en) * 2008-01-18 2009-07-22 晶元光电股份有限公司 Light emitting element and method for manufacturing the same
CN101996892A (en) * 2009-08-17 2011-03-30 晶元光电股份有限公司 System-level optoelectronic structure and fabrication method thereof
US20140159066A1 (en) * 2012-12-11 2014-06-12 LuxVue Technology Corporation Stabilization structure including sacrificial release layer and staging bollards
CN105493297A (en) * 2015-05-21 2016-04-13 歌尔声学股份有限公司 Transfer method, manufacturing method, device and electronic equipment of micro light emitting diode
WO2016183844A1 (en) * 2015-05-21 2016-11-24 Goertek.Inc Transferring method, manufacturing method, device and electronic apparatus of micro-led
CN105036066A (en) * 2015-07-14 2015-11-11 华进半导体封装先导技术研发中心有限公司 Surface treatment method for protective cover of wafer level package
CN106058010A (en) * 2016-07-26 2016-10-26 深圳市华星光电技术有限公司 Micro light emitting diode array's transfer printing method

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11056611B2 (en) 2018-09-11 2021-07-06 Facebook Technologies, Llc Mesa formation for wafer-to-wafer bonding
US11145786B2 (en) 2018-09-11 2021-10-12 Facebook Technologies, Llc Methods for wafer-to-wafer bonding
US11342479B2 (en) 2018-09-11 2022-05-24 Facebook Technologies, Llc Reducing bowing of materials before wafer-to-wafer bonding for LED manufacturing
JP2020096144A (en) * 2018-12-14 2020-06-18 Tdk株式会社 Element array manufacturing method and specific element removing method
KR20210153732A (en) * 2019-06-17 2021-12-17 청두 비스타 옵토일렉트로닉스 씨오., 엘티디. Display device, display panel and manufacturing method thereof
KR102604712B1 (en) * 2019-06-17 2023-11-22 청두 비스타 옵토일렉트로닉스 씨오., 엘티디. Display device, display panel and method of manufacturing the same
WO2021101650A1 (en) * 2019-11-18 2021-05-27 Facebook Technologies, Llc Bonding of light emitting diode arrays
WO2021236382A1 (en) * 2020-05-18 2021-11-25 Nanosys, Inc. Subpixel light emitting diodes for direct view display and methods of making the same
US11973172B2 (en) 2020-05-18 2024-04-30 Glo Technologies Llc Subpixel light emitting diodes for direct view display and methods of making the same
US12439757B2 (en) 2020-05-18 2025-10-07 Samsung Electronics Co., Ltd. Subpixel light emitting diodes for direct view display and methods of making the same
CN112967961A (en) * 2020-05-28 2021-06-15 重庆康佳光电技术研究院有限公司 A transfer method and device
CN112967961B (en) * 2020-05-28 2022-05-31 重庆康佳光电技术研究院有限公司 Transfer method and device

Also Published As

Publication number Publication date
US11024611B1 (en) 2021-06-01
CN109496351B (en) 2022-09-09
US20210151418A1 (en) 2021-05-20
CN109496351A (en) 2019-03-19

Similar Documents

Publication Publication Date Title
US11024611B1 (en) Micro-LED array transfer method, manufacturing method and display device
US11581291B2 (en) Micro-LED display device and a manufacturing method thereof
US10566494B2 (en) Micro-LED transfer method and manufacturing method
US10319697B2 (en) Transferring method, manufacturing method, device and electronic apparatus of micro-LED
CN104465479B (en) Flexible display substrates motherboard and the preparation method of flexible display substrates
US10193012B2 (en) Transferring method, manufacturing method, device and electronic apparatus of micro-LED
US10141287B2 (en) Transferring method, manufacturing method, device and electronic apparatus of micro-LED
US10224308B2 (en) Transferring method, manufacturing method, device and electronic apparatus of micro-LED
CN108140664B (en) Micro light emitting diode array transfer method, manufacturing method and display device
JP6650941B2 (en) Micro light emitting diode transfer method, manufacturing method, apparatus and electronic equipment
US20190096859A1 (en) Micro-LED Transfer Method, Manufacturing Method and Display Device
CN105723528A (en) Transfer method, manufacturing method, device and electronic equipment of micro light emitting diode
JP2017535967A (en) Flip die assembly method, manufacturing method, apparatus, and electronic apparatus
CN105518877A (en) Micro light-emitting diode pre-elimination method, manufacturing method, apparatus and electronic equipment
CN103681357B (en) Flexible display device and preparation method thereof, display unit
US10276592B2 (en) Display substrate, method of fabricating the same, display panel and pressure welding device
CN103000491A (en) Method for manufacturing flexible display device
US9717143B2 (en) Method for fabricating flexible substrate and flexible substrate prefabricated component
CN203521391U (en) Flexible substrate prefabricated assembly
CN102315202B (en) Substrate strip with lines and manufacturing method thereof
CN108878666A (en) Flexible OLED display and its method for being bonded support membrane
KR20190060287A (en) Method of trasferring micro-device array
CN110791220A (en) Transparent polyimide composite film for flexible display and manufacturing method thereof
US20080160673A1 (en) Assembly of thin die coreless package
Chen et al. 33‐3: Study of Bonding Technology on Flexible Substrate

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17913084

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17913084

Country of ref document: EP

Kind code of ref document: A1