METHOD FOR TRANSFERRING ELECTRONIC COMPONENT

A method for transferring electronic components. First, a transfer substrate is provided, which has a surface on which a plurality of cavities are formed, such that the carrier substrate to face the surface of the transfer substrate in a manner that a portion of the electronic components are arranged corresponding to at least a portion of the plurality of cavities on the transfer substrate, and then releasing and allowing the portion of electronic components that are arranged corresponding to the at least a portion of the plurality of cavities to fall into the cavities.

CROSS-REFERENCE TO RELATED APPLICATION

This non-provisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No(s). 110100614 filed in Taiwan, R.O.C. on Jan. 7, 2021, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to transfer methods, and in particular to a method for transferring electronic components.

2. Description of the Related Art

Electronic devices nowadays have increasingly complicated functions, and the required numbers of their electronic components are on the rise, thanks to ever-changing technology and ever-increasing consumer needs. Ongoing trend toward miniaturization of electronic components is required to downsize electronic devices and enhance their performance.

For instance, light emitting diode (LED) display devices are one of the topics of research carried out on display units. However, to meet the requirement for high resolution, LED display devices are trending toward microscale LEDs arranged in an array and the resultant tremendous need of transfer.

Therefore, it is important to provide a method for transferring electronic components rapidly and precisely.

BRIEF SUMMARY OF THE INVENTION

An objective of the present disclosure is to provide a method for transferring electronic components, allowing the carrier substrate to face a surface of the transfer substrate in a manner that a portion of the electronic components are arranged corresponding to at least a portion of a plurality of cavities on the transfer substrate, and releasing and allowing the portion of electronic components that are arranged corresponding to the at least a portion of the plurality of cavities to fall into the cavities. The transfer substrate has a surface on which the plurality of cavities are formed. The cavities ensure that the electronic components fall into correct positions when released. Therefore, the method is effective in transferring electronic components rapidly and precisely.

Therefore, according to the present disclosure, a method for transferring electronic components is provided, such that the electronic components that are not arranged corresponding to the at least a portion of the plurality of cavities come into contact with the surface of the transfer substrate on which the plurality of cavities are not formed, and releasing and allowing the portion of electronic components that are arranged corresponding to the at least a portion of the plurality of cavities to fall into the cavities, thereby shortening the distance which separates the released electronic components from the transfer substrate. The transfer substrate has cavities for receiving electronic components of the carrier substrate. The cavities ensure that the electronic components fall into correct positions when released. Therefore, the method is effective in transferring electronic components rapidly and precisely and achieving satisfactory production yield.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1AthroughFIG. 1Dare schematic views of a process flow of a method for transferring electronic components according to an embodiment of the present disclosure. Referring toFIG. 1A, a carrier substrate110and a transfer substrate200are provided. The carrier substrate110carries a plurality of electronic components111. The transfer substrate200has a surface210on which a plurality of cavities211are formed. The carrier substrate110is, for example, an adhesive film or a substrate with an adhesive film, and is adapted to adhere to and carry the plurality of electronic components111. The adhesive film is, for example, made of polyimide, but the present disclosure is not limited thereto. The transfer substrate200is a transparent substrate, for example, glass substrate, quartz substrate or sapphire substrate, but the present disclosure is not limited thereto. The plurality of electronic components111carried by the carrier substrate110have identical dimensions. The dimensions of the electronic components111are equal to or greater than 100 μm. The electronic components111are, for example, integrated circuit chips, but the present disclosure is not limited thereto. The dimensions of the electronic components111are not greater than 100 μm. The electronic components111are, for example, LED chips, for example, Mini LED chips or Micro LED chips, but the present disclosure is not limited thereto. The depth of the plurality of cavities is equal to or less than the height of the electronic components111. The plurality of cavities211are formed on the surface210of the transfer substrate200by a laser ablation or a chemical etching, but the present disclosure is not limited thereto. The laser for use in the laser ablation is, for example, visible light or invisible light. The chemical etching is, for example, dry etching or wet etching, but the present disclosure is not limited thereto.

Referring toFIG. 1A, the plurality of electronic components111on the carrier substrate110face the surface210of the transfer substrate200in a manner that a portion of the electronic components111(for example, electronic components111a) are arranged corresponding to at least a portion of the plurality of cavities221on the transfer substrate200but the other electronic components111(for example, electronic components111b) not to align with the cavities211on the transfer substrate200, by image-based positioning, but the present disclosure is not limited thereto.

Referring toFIG. 1B, the relative position of the carrier substrate110to the transfer substrate200are changed till the electronic components111that are not arranged corresponding to the at least a portion of the plurality of cavities211come into contact with the surface210of the transfer substrate200on which the plurality of cavities211are not formed, for example, by moving one of the carrier substrate100and the transfer substrate200toward the other, and the electronic components111(for example, electronic components111b) not aligned with the cavities211come into contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200. A force sensing or an optical distance sensing determines whether the electronic components111not aligned with the cavities211are in contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200.

Referring toFIG. 1C, the electronic components111(for example, electronic components111a) that are arranged corresponding to the at least a portion of the plurality of cavities211are released and allowed to fall into the cavities. The release process is started by transferring energy to, for example, the electronic components111aligned with the cavities211, such that the adhesiveness of the adhesive layer of the carrier substrate110diminishes, thereby releasing the electronic components111from the carrier substrate110. The energy transfer is carried out by emitting a laser beam or ultrasonic waves toward the adhesive layers of the electronic components111aligned with the cavities211, as shown inFIG. 1C, but the present disclosure is not limited thereto.

Referring toFIG. 1D, the relative position of the carrier substrate110to the transfer substrate200is changed to draw the two substrates away from each other, such that one of the carrier substrate100and transfer substrate200moves away from the other, and the electronic components111aligned with the cavities211are not in contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200. In this embodiment, the electronic components111disposed on the carrier substrate100but not aligned with the cavities211are further used in the next instance of transfer.

In this embodiment, the method for transferring the present disclosure enables the electronic components111disposed on the carrier substrate110but not aligned with the cavities211to come into contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200, and then allows the electronic components111aligned with the cavities211to be released, such that the distance between the electronic components111on the carrier substrate110and the surface210of the transfer substrate200is capped by the height of the electronic components111, so as to reduce the distance which separates the electronic components111from the transfer substrate200and lower the chance that the electronic components111will, in the course of its fall, drift or separate from the transfer substrate200. The transfer substrate200has the cavities211for receiving the electronic components111of the carrier substrate110. When released, the electronic components111are guided by the cavities211to their correct positions. Therefore, the method for transferring electronic components of the present disclosure enhances production yield.

The method for transferring LED chips is described above step by step and below generally.

Referring toFIG. 2A, the method for transferring electronic components illustrated with FIG. lA throughFIG. 1Dprovides a carrier substrate110and a transfer substrate200. The plurality of electronic components111on the carrier substrate110face the surface210of the transfer substrate200. The plurality of cavities211are disposed on the surface210. A portion of the electronic components111are aligned with the plurality of cavities211on the transfer substrate200. Then, the relative position of the carrier substrate110to the transfer substrate200is changed, and the electronic components111not aligned with the cavities211come into contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200. Then, the electronic components111disposed on the carrier substrate110and aligned with the cavities211are released to the cavities211. The electronic components111are LED chips which emit red (R) light.

Referring toFIG. 2B, the method for transferring electronic components illustrated withFIG. 1AthroughFIG. 1Dprovides a carrier substrate120. The plurality of electronic components121on the carrier substrate120face the surface210of the transfer substrate200. The plurality of cavities211are disposed on the surface210. A portion of the electronic components121(for example, electronic components121a) are aligned with the cavities211disposed on the transfer substrate200but not receiving the electronic components111. Then, the relative position of the carrier substrate120to the transfer substrate200is changed, and the electronic components121(for example, electronic components121b) not aligned with the cavities211come into contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200. Then, the electronic components111disposed on the carrier substrate120and aligned with the cavities211are released to the cavities211. The electronic components121are LED chips which emit green (G) light.

Referring toFIG. 2C, the method for transferring electronic components illustrated withFIG. 1AthroughFIG. 1Dprovides a carrier substrate130. The plurality of electronic components131on the carrier substrate130face the surface210of the transfer substrate200. The plurality of cavities211are disposed on the surface210. A portion of the electronic components131(for example, electronic components131a) are aligned with the cavities211disposed on the transfer substrate200but not receiving the electronic components111or electronic components121. Then, the relative position of the carrier substrate130to the transfer substrate200is changed, and the electronic components131(for example, electronic components131b) not aligned with the cavities211come into contact with a cavity-free part (i.e., a part free of the cavities211) of the surface210of the transfer substrate200. Then, the electronic components131disposed on the carrier substrate130and aligned with the cavities211are released to the cavities211. The electronic components131are LED chips which emit blue (B) light. Therefore, the cavities211of the transfer substrate200each receive one of the electronic component111, electronic component121and electronic component131. The electronic components111, electronic components121and electronic components131are arranged in a pixel array in the plurality of cavities211of the transfer substrate200.

Referring toFIG. 2D, a carrier substrate300is provided. The carrier substrate300has a surface310with an adhesive film311thereon.

Referring toFIG. 2E, the surface310of the carrier substrate300faces the surface210of the transfer substrate200. The plurality of cavities211are disposed on the surface210. The relative position of the carrier substrate300to the transfer substrate200is changed. The adhesive film311of the carrier substrate300comes into contact with and thus adheres to the electronic components111,121,131in the plurality of cavities211of the transfer substrate200.

Referring toFIG. 2F, the relative position of the carrier substrate300to the transfer substrate200is changed to draw the two substrates away from each other, such that the electronic components111,121or131received in the cavities211are adhered to the surface310of the carrier substrate300and leave the cavities211and thus are transferred to the carrier substrate300.

In this embodiment, the pixel array formed on the transfer substrate200depends on the pixel array of the circuit substrate of a display device. Therefore, the electronic components111,121,131transferred to the carrier substrate300and pixel array thus formed can be transferred to the circuit substrate of the display device in one single instance of a transfer process. Therefore, the method for transferring electronic components of the present disclosure is effective in transferring a large number of pixels on the circuit substrate rapidly and precisely, reducing the transfer cost incurred in a display device manufacturing process, and achieving satisfactory production yield.

In conclusion, the method for transferring electronic components of the present disclosure enables electronic components disposed on a carrier substrate but not aligned with cavities therein to come into contact with a cavity-free part of a surface of a transfer substrate and then allows the electronic components aligned with the cavities to be released, so as to shorten the distance which separates the electronic components of the carrier substrate from the surface of the transfer substrate and lower the chance that the electronic components will, in the course of its fall, drift or separate from the transfer substrate. Furthermore, the transfer substrate has cavities for receiving the electronic components of the carrier substrate, such that the released electronic components are guided by the cavities to their correct positions. Therefore, the method for transferring electronic components of the present invention has satisfactory production yield.