CN114141666A

CN114141666A - Efficient LED crystal grain sorting method

Info

Publication number: CN114141666A
Application number: CN202111435230.7A
Authority: CN
Inventors: 郭祖福; 官婷; 彭超; 刘奇艳
Original assignee: Xiangneng Hualei Optoelectrical Co Ltd
Current assignee: Xiangneng Hualei Optoelectrical Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-03-04

Abstract

The application discloses a high-efficiency LED crystal grain sorting method, which comprises the following steps: step 1, during first sorting, collecting no more than 30 scattered Bins on a plurality of wafers into the same designated grade, and continuously discharging the scattered Bins on the next blue film after the scattered Bins are fully discharged on the first blue film; and 2, sorting the part of the dispersed Bin on the blue film into the corresponding electrical grade, and sorting the rest dispersed Bin on the blue film after gathering until all the dispersed Bin are sorted into the corresponding electrical grade. The method and the device have the advantages that the one-time centralized sorting of the scattered Bin on different wafers is realized, the time for changing iron sheets (electrical property grade) of the sorting machine is shortened, and the productivity of chips is increased.

Description

Efficient LED crystal grain sorting method

Technical Field

The invention relates to the technical field of LEDs, in particular to a high-efficiency LED crystal grain sorting method.

Background

In the LED industry, chip sorting is an indispensable process, and the specific operation is as follows: the wafer is placed at one end of the sorting machine, a plurality of iron sheets with blue films are placed at the other end of the sorting machine, different iron sheets correspond to different electrical ranges, and chips on the wafer are picked out by a mechanical arm and placed on the blue films corresponding to the iron sheets. Because the mechanical arm sequentially picks the crystal grains during operation, and the electrical ranges of the N chips in the same area on the wafer are the same or similar, when the electrical ranges are divided into a small number of grades, the number of times of drawing the iron sheets is small, and the time consumed by each drawing can be ignored. However, as the market demands for electrical performance range are gradually refined, the dies on the same wafer need to be sorted to more and more iron sheets, and particularly for some loose bins, that is, the number of chips included in the corresponding electrical performance level of the chip is small, the frequency of occurrence on the wafer is higher and higher, which has a great influence on the sorting speed of the LED chips.

For example, when an ASM sorting machine is used to sort LED dies, for a certain electrical grade containing 5000 chips, only one iron sheet pulling operation is required (30 s is consumed), the picking time for each chip is 50ms, and if the 5000 chips are further subdivided into 10 electrical grades, the chip picking time is not changed, but 9 additional iron sheet pulling operations are required, which means that waste is serious for chip productivity. In actual production, electrical levels including several or more than ten chips are common, and more time is wasted, but technicians in the industry do not pay attention to the electrical levels and a targeted solution is not provided.

In summary, a new chip sorting scheme is needed in the industry to reduce the yield reduction problem caused by the increase of Bin.

Disclosure of Invention

The application aims to provide an efficient LED crystal grain sorting method, which can meet the existing electrical property level subdivision requirements and simultaneously improve the chip productivity. The technical scheme of the application is as follows:

a high-efficiency LED crystal grain sorting method comprises the following steps:

step 1, collecting scattered Bin on a plurality of wafers into the same designated grade during first sorting;

and 2, sorting each bulk Bin into a corresponding electrical property grade.

In some specific embodiments, in step 1, after the first blue film is filled with the scattered bins on the plurality of wafers, the scattered bins continue to be discharged on the next blue film; in step 2, at least part of the bulk bins are reclassified: and sorting the parts of the dispersed bins on the blue film into corresponding electrical property grades, and collecting and then sorting the rest parts of the dispersed bins on the blue film.

In some specific embodiments, the summarizing operation for the loose Bin in step 1 and step 2 is: when the system shifts, the sorting machine system monitors the number of Bin drops, changes the grade number of the Bin drops, the number of which does not exceed N electric property grades, into the grade number of the appointed grade, and simultaneously reserves the original electric property grade data of each bulk Bin, wherein N is the preset maximum chip number of the bulk Bin.

In some specific embodiments, 10 ≦ N ≦ 100.

In some embodiments, the number of reclassifications in step 2 is two or more.

The technical scheme provided by the application has at least the following beneficial effects:

the method and the device solve the problem that the time for selecting the iron sheets (electrical property grade) of the sorting machine is not long when the scattered Bin is sorted, reduce the times for drawing and replacing the Bin of each wafer, increase the quantity of each scattered Bin substantially after all the scattered Bin of a plurality of wafers are gathered together, avoid the low-efficiency production mode that each scattered Bin needs to be drawn and replaced by the Bin and then only selects a few Bin, ensure that more crystal grains can be sorted out when the Bin is replaced at each time, save the time for sorting the crystal grains, improve the production efficiency, increase the productivity and create more economic benefits.

Detailed Description

In order to facilitate understanding of the present application, the technical solutions in the present application will be described more fully and in detail with reference to some preferred embodiments, but the scope of the present application is not limited to the following specific embodiments, and all other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without creative efforts will fall within the scope of the present application.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present application.

and 2, sorting each bulk Bin into a corresponding electrical property grade.

Specifically, in step 1, if the number of the scattered bins is large, after the scattered bins on the plurality of wafers are arranged in the first blue film, the scattered bins can be continuously arranged on the second blue film and the third blue film, and so on. In the step 2, if the number of the loose bins corresponding to a certain electrical property level obtained by the collection on the blue film is large, the partial loose bins can be sorted into the corresponding electrical property level, and for the partial loose bins with a small number even after the partial loose bins are once collected, a secondary collection and sorting mode can be adopted, that is, the above process is repeated, the partial loose bins are collected again, and the partial loose bins are further sorted after being accumulated into a large number. According to the actual sorting condition, the times of summarizing and re-sorting can be more until all the scattered Bins are sorted into the corresponding electrical property grade.

The operation of summarizing the bulk bins in the step 1 and the step 2 is as follows: when the system shifts, the sorting machine system monitors the number of Bin drops, changes the grade number of the Bin drops, the number of which does not exceed N electric property grades, into the grade number of the appointed grade, and simultaneously reserves the original electric property grade data of each bulk Bin, wherein N is the preset maximum chip number of the bulk Bin.

Example 1

For 1000A products, the bulk Bin less than 30 particles is set to be shifted to the same grade, and the reclassification is realized by shifting the sorting machine again after the summary.

According to statistics, 30 or less bulk bins in the 1000 a products were classified into 9577 bulk bins, and the total number of the bulk bins was 162062. According to the calculation that the time for changing Bin by one-time drawing of a machine table is 20s, 9577 multiplied by 20 is required to be 191540s, which is about equal to 53 hours, 2.2 days, namely the scattered bins influence the 2.2-day capacity of a sorting machine, and the actual capacity is only 162062, namely 0.16KK, which is less than 0.1 percent of the number of all crystal grains in 1000A products, so that the production efficiency is seriously reduced.

By adopting the method, 2.2 days of time for picking chips by the sorting machine can be saved when 1000 wafers are processed, and 1.98KK crystal grains can be produced when one sorting machine normally works for 2.2 days, so that the part is the excess capacity, the capacity is improved by 1.2% compared with the previous capacity, and the progress is obvious.

The method has the advantages of obvious effect, higher economic benefit, simple operation process, suitability for various chip sorting equipment in the market and popularization value when being applied to actual production.

The above description is only a few examples of the present application and does not limit the scope of the claims of the present application, and it will be apparent to those skilled in the art that various modifications and variations can be made in the present application. Any improvement or equivalent replacement, which can be directly or indirectly applied to other related technical fields by using the content of the specification of the application, is within the spirit and principle of the application and is included in the protection scope of the patent of the application.

Claims

1. A high-efficiency LED crystal grain sorting method is characterized by comprising the following steps:

and 2, sorting each bulk Bin into a corresponding electrical property grade.

2. The method for sorting the LED crystal particles according to claim 1, wherein in the step 1, after the scattered Bin on the plurality of wafers is fully arranged in the first blue film, the scattered Bin is continuously arranged on the next blue film; in step 2, at least part of the bulk bins are reclassified: and sorting the parts of the dispersed bins on the blue film into corresponding electrical property grades, and collecting and then sorting the rest parts of the dispersed bins on the blue film.

3. The method for sorting the LED dies according to claim 2, wherein the operation of summing the scattered Bin in step 1 and step 2 is: when the system shifts, the sorting machine system monitors the number of Bin drops, changes the grade number of the Bin drops, the number of which does not exceed N electric property grades, into the grade number of the appointed grade, and simultaneously reserves the original electric property grade data of each bulk Bin, wherein N is the preset maximum chip number of the bulk Bin.

4. The method of claim 3, wherein N is 10-100.

5. The method as claimed in claim 4, wherein the number of reclassifications in step 2 is two or more.