US-12622323-B2 - Semiconductor light emitting element chip integrated device and manufacturing method thereof

US12622323B2US 12622323 B2US12622323 B2US 12622323B2US-12622323-B2

Abstract

A liquid-droplet-like ink containing a plurality of vertical semiconductor light emitting element chips 40 , each of which has a p-side electrode and an n-side electrode on the upper surface and the lower surface and is configured such that one of the p-side electrode and the n-side electrode is more strongly attracted to a magnetic field than the other is supplied to a chip joining part 421 on a lower electrode 420 on a mounting substrate 400 , the semiconductor light emitting element chips 40 in the ink are joined to the chip joining part by applying an external magnetic field such that one of the p-side electrode and the n-side electrode faces to the chip joining part, and thereafter an upper electrode 430 having an upper electrode main line part 431 and a plurality of upper electrode branch line parts 432 which are connected by a thin film fuse 433 each other is formed as the upper layer of the semiconductor light emitting element chips 40 such that the other of the p-side electrode and the n-side electrode of the semiconductor light emitting element chip 40 and the upper electrode branch line part 432 are electrically connected each other.

Inventors

Motonobu Takeya

Assignees

ULDTEC CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20210615
Priority Date: 20200620

Claims (20)

1 . A semiconductor light emitting element chip integrated device, comprising: a substrate having a lower electrode on one major surface, a chip joining part on which semiconductor light emitting element chips are to be joined which is formed by a part of an upper surface or a protrusion or a concavity formed on a part of an upper surface of the lower electrode, a plurality of vertical semiconductor light emitting element chips joined to the chip joining part, each of which has a p-side electrode and an n-side electrode on an upper surface and a lower surface of the semiconductor light emitting element chip, respectively and is configured such that one of the p-side electrode or the n-side electrode is more strongly attracted to a magnetic field than the other; and an upper electrode as an upper layer of the semiconductor light emitting element chips having a main line part and a plurality of branch line parts which are connected to each other by a thin film fuse, the semiconductor light emitting element chips being joined to the chip joining part such that the one of the p-side electrode or the n-side electrode faces the chip joining part, the one of the p-side electrode or the n-side electrode and the lower electrode being electrically connected to each other, and the other of the p-side electrode or the n-side electrode of at least one semiconductor light emitting element chip the branch line parts of the upper electrode being electrically connected to each other.
2 . The semiconductor light emitting element chip integrated device according to claim 1 wherein the upper electrode and the lower electrode are formed for respective circuit units.
3 . The semiconductor light emitting element chip integrated device according to claim 1 wherein one pixel is formed by an area including more than 3 circuit units adjacent to each other.
4 . The semiconductor light emitting element chip integrated device according to claim 1 wherein the one of the p-side electrode or the n-side electrode contains soft magnetic materials.
5 . The semiconductor light emitting element chip integrated device according to claim 1 wherein the semiconductor light emitting element chip has the chip size not larger than 10 μm×10 μm and the thickness not larger than 10 μm.
6 . The semiconductor light emitting element chip integrated device according to claim 1 wherein the chip joining part is formed such that hydrophilic property or lipophilic property of the chip joining part is higher than that of a peripheral part of the chip joining part.
7 . The semiconductor light emitting element chip integrated device according to claim 6 wherein a predetermined group of chip joining parts which are adjacent to each other are mutually connected by an area which is formed to have the high hydrophilic property or lipophilic property similar to the chip joining part.
8 . A semiconductor light emitting element chip integrated device, comprising: a substrate having a lower electrode having a main line part and a plurality of branch line parts which are connected to each other by a thin film fuse on one major surface, a chip joining part which is formed by an upper surface of the branch line part of the lower electrode, to which semiconductor light emitting element chips are to be joined, a plurality of vertical semiconductor light emitting element chips joined to the chip joining part, each of which has a p-side electrode and an n-side electrode on an upper surface and a lower surface of the semiconductor light emitting element chip, respectively and is configured such that one of the p-side electrode or the n-side electrode is more strongly attracted to a magnetic field than the other; and an upper electrode as an upper layer of the semiconductor light emitting element, the semiconductor light emitting element chips being joined to the chip joining part such that the one of the p-side electrode or the n-side electrode faces the chip joining part, the one of the p-side electrode or the n-side electrode and the branch line part of the lower electrode being electrically connected to each other, and the other of the p-side electrode or the n-side electrode of at least one semiconductor light emitting element chip and the upper electrode being electrically connected to each other.
9 . The semiconductor light emitting element chip integrated device according to claim 8 wherein the upper electrode and the lower electrode are formed for respective circuit units.
10 . The semiconductor light emitting element chip integrated device according to claim 8 wherein one pixel is formed by an area including more than 3 circuit units adjacent to each other.
11 . The semiconductor light emitting element chip integrated device according to claim 8 wherein the one of the p-side electrode or the n-side electrode contains soft magnetic materials.
12 . The semiconductor light emitting element chip integrated device according to claim 8 wherein the semiconductor light emitting element chip has the chip size not larger than 10 μm×10 μm and the thickness not larger than 10 μm.
13 . The semiconductor light emitting element chip integrated device according to claim 8 wherein the chip joining part is formed such that hydrophilic property or lipophilic property of the chip joining part is higher than that of a peripheral part of the chip joining part.
14 . The semiconductor light emitting element chip integrated device according to claim 13 wherein a predetermined group of chip joining parts which are adjacent to each other are mutually connected by an area which is formed to have the high hydrophilic property or lipophilic property similar to the chip joining part.
15 . A method of manufacturing a semiconductor light emitting element chip integrated device, comprising steps of: supplying a liquid-droplet-like ink containing a liquid and a plurality of vertical semiconductor light emitting element chips, each of which has a p-side electrode and an n-side electrode on an upper surface and a lower surface of the semiconductor light emitting element chip, respectively and is configured such that one of the p-side electrode or the n-side electrode is more strongly attracted to a magnetic field than the other of the p-side electrode or the n-side electrode to a chip joining part formed by a part of an upper surface or a protrusion or a concavity formed on a part of an upper surface of a lower electrode on a substrate having the lower electrode on one major surface, to which semiconductor light emitting element chips are to be joined, joining the semiconductor light emitting element chips to the chip joining part by applying an external magnetic field from the opposite side with respect to the substrate such that the one of the p-side electrode or the n-side electrode faces the chip joining part and electrically connecting the one of the p-side electrode or the n-side electrode and the lower electrode; and forming an upper electrode as an upper layer of the semiconductor light emitting device chips having a main line part and a plurality of branch line parts which are electrically connected to each other by a thin film fuse such that the other of the p-side electrode or the n-side electrode of at least one semiconductor light emitting element chip and the branch line part of the upper electrode are electrically connected to each other.
16 . The method of manufacturing a semiconductor light emitting element chip integrated device according to claim 15 further comprising a step of testing the semiconductor light emitting element chip after the upper electrode is formed and cutting the thin film fuse between the branch line part to which the defective semiconductor light emitting element chip is connected and the main line part.
17 . The method of manufacturing a semiconductor light emitting element chip integrated device according to claim 15 wherein the ink is ejected from the tip of a nozzle to the chip joining part by an inkjet printing method.
18 . A method of manufacturing a semiconductor light emitting element chip integrated device, comprising steps of: supplying a liquid-droplet-like ink containing a liquid and a plurality of vertical semiconductor light emitting element chips, each of which has a p-side electrode and an n-side electrode on an upper surface and a lower surface of the semiconductor light emitting element chip, respectively and is configured such that one of the p-side electrode or the n-side electrode is more strongly attracted to a magnetic field than the other of the p-side electrode or the n-side electrode to a chip joining part formed by an upper surface of branch line parts of a lower electrode on a substrate having a main line part and a plurality of branch line parts which are electrically connected to each other by a thin film fuse on one major surface, to which semiconductor light emitting element chips are to be joined, joining the semiconductor light emitting element chips in the ink to the chip joining part by applying an external magnetic field from the opposite side with respect to the substrate such that the one of the p-side electrode or the n-side electrode faces the chip joining part and electrically connecting the one of the p-side electrode or the n-side electrode and the branch line parts of the lower electrode; and forming an upper electrode as an upper layer of the semiconductor light emitting element chips such that the other of the p-side electrode or the n-side electrode of at least one semiconductor light emitting element chip and the upper electrode are electrically connected to each other.
19 . The method of manufacturing a semiconductor light emitting element chip integrated device according to claim 18 further comprising a step of testing the semiconductor light emitting element chip after the upper electrode is formed and cutting the thin film fuse between the branch line part to which the defective semiconductor light emitting element chip is connected and the main line part.
20 . The method of manufacturing a semiconductor light emitting element chip integrated device according to claim 18 wherein the ink is ejected from the tip of a nozzle to the chip joining part by an inkjet printing method.

Description

TECHNICAL FIELD The present invention relates to a semiconductor light emitting element chip integrated device and manufacturing method thereof which are suitably applied to, for example, a micro LED display in which a number of small-sized longitudinal (or vertical) micro light emitting diode (LED) chips are integrated on a substrate. BACKGROUND ART At present, the mainstream of displays such as thin type televisions, smartphones and the like are liquid crystal displays (LCDs) and organic EL displays (OLEDs). Regarding LCDs, the output light quantity is about a tenth of the light quantity of the backlight as pixels become small. Regarding OLEDs, although theoretical power efficiency is high, the output light quantity of real products remains in level equal to LCDs. Micro LED displays receive attention as displays having high luminance and high efficiency (low power consumption) far surpassing LCDs and OLEDs. Direct light emission micro LED displays have high efficiency. However, in order to realize micro LED displays, it is necessary to arrange several tens million micro LED chips having the size of order of several μm to tens of μm. As methods for arranging such a large number of micro LED chips on a mounting substrate, proposed conventionally have been a method using a chip sorter, a method using a multichip transfer device (see patent literatures 1 and 2), a chip arranging method using chip ejection by laser irradiation and a liquid (see patent literature 3), a device (chip) arranging method using a magnetic film (see patent literatures 4 and 5) and the like. However, according to the methods proposed in the patent literatures 1-5, it has been difficult to realize micro LED displays at small cost. Against the background described above, present inventor has proposed a method of manufacturing a semiconductor chip integrated device which can realize the micro LED display at small cost (see patent literature 6). According to the patent literature 6, the micro LED display is manufactured by ejecting an ink in which micro LED chips, each of which is configured such that the p-side electrode side is more strongly attracted to a magnetic field than the n-side electrode side, for example, are dispersed in a liquid to a chip joining part on one major surface of a substrate and joining the p-side electrode side of the micro LED chips to the chip joining part by applying an external magnetic field to the substrate from below it. PRIOR ART LITERATURE Patent Literature [PATENT LITERATURE 1] Laid-open publication No. 2017-531915[PATENT LITERATURE 2] Laid-open publication No. 2017-500757[PATENT LITERATURE 3] Laid-open publication No. 2005-174979[PATENT LITERATURE 4] Laid-open publication No. 2003-216052[PATENT LITERATURE 5] Laid-open publication No. 2016-25205[PATENT LITERATURE 6] Patent Gazette No. 6694222 SUMMARY OF INVENTION Subjects to be Solved by Invention According to the method of manufacturing a micro LED display described in the patent literature 6, it is possible to realize micro LED displays at small cost. However, when defection of micro LED chips is found by a test, it is not always easy to repair the micro LED display. Therefore, there is still room for improvement. Therefore, the subject to be solved by the invention is to provide a semiconductor light emitting element chip integrated device and a manufacturing method thereof which can manufacture various semiconductor light emitting element chip integrated devices such as micro LED displays and the like, and which can easily repair the semiconductor light emitting element chip integrated device when defection of semiconductor light emitting element chips such as micro LED chips and the like is found by a test after the semiconductor light emitting element chips are mounted on a substrate. Means to Solve the Subjects In order to solve the object, according to the invention, there is provided a method of manufacturing a semiconductor light emitting element chip integrated device, comprising steps of: supplying a liquid-droplet-like ink containing a liquid and a plurality of vertical semiconductor light emitting element chips, each of which has a p-side electrode and an n-side electrode on the upper surface and the lower surface and is configured such that one of the p-side electrode and the n-side electrode is more strongly attracted to a magnetic field than the other of the p-side electrode and the n-side electrode to a chip joining part formed by a part of the upper surface or a protrusion or a concavity formed on a part of the upper surface of a lower electrode on a substrate having the lower electrode on one major surface, to which semiconductor light emitting element chips are to be joined,joining the semiconductor light emitting element chips to the chip joining part by applying an external magnetic field from the opposite side with respect to the substrate such that the one of the p-side electrode and the n-side electrode faces the chip joining p