CN211788923U

CN211788923U - System for be used for quick test electric leakage LED chip electric leakage point

Info

Publication number: CN211788923U
Application number: CN202020595168.2U
Authority: CN
Inventors: 李进; 温俊杰; 赵旭林; 周欢
Original assignee: Foshan Nationstar Semiconductor Co Ltd
Current assignee: Foshan Nationstar Semiconductor Co Ltd
Priority date: 2020-04-20
Filing date: 2020-04-20
Publication date: 2020-10-27
Anticipated expiration: 2030-04-20

Abstract

The utility model discloses a system for rapidly testing electric leakage points of an electric leakage LED chip, which comprises a power supply, a testing substrate for placing the electric leakage LED chip, color-changing printing ink sprayed on the electric leakage LED chip, and a point testing device which is connected with the power supply and feeds reverse voltage into the electric leakage LED chip, wherein the color-changing printing ink can show different colors at different temperatures; after the reverse voltage is applied to the leakage LED chip, the color of the leakage point is different from that of the non-leakage point. The utility model is used for test electric leakage LED chip leakage point's system fast, simple structure, it is with low costs, but the short-term test goes out electric leakage LED chip's leakage point position.

Description

System for be used for quick test electric leakage LED chip electric leakage point

Technical Field

The utility model relates to a LED chip test technical field especially relates to a system for be used for quick test electric leakage LED chip electric leakage point.

Background

The reliability of the LED chip is seriously affected by the leakage of the LED chip. After the LED chip leaks electricity, the material of the LED chip is heated and rapidly degraded and decomposed, so as to generate a larger leakage current, and finally the chip is burned down.

In the production process of the LED chips, if the batch of electric leakage LED chips appear, technicians need to find out electric leakage points of the electric leakage LED chips, carry out electric leakage analysis on the electric leakage LED chips, find out the reason of electric leakage, and then can prevent more electric leakage LED chips from appearing by changing the production process.

The existing point detection equipment can only detect whether the LED chip leaks electricity, but cannot find out the leakage point of the leaked LED chip.

The existing equipment capable of detecting the electric leakage point of the electric leakage LED chip is an infrared thermal imager (EMMI). The infrared thermal imager receives the thermal radiation distribution generated after the fault point is electrified, so that the position of the fault point (Hot Spot and bright Spot) is positioned, and the depth position of the fault point of the chip can be estimated by utilizing the time difference of thermal radiation conduction of the fault point. However, the infrared thermal imaging instrument is expensive and not suitable for analysis in common chip and packaging factories.

Disclosure of Invention

The utility model aims to solve the technical problem that a system for be used for quick test electric leakage LED chip electric leakage point is provided, simple structure, it is with low costs, but the short-term test goes out electric leakage LED chip's electric leakage point position.

In order to solve the technical problem, the utility model provides a system for test electric leakage point of electric leakage LED chip fast, including the power, be used for placing electric leakage LED chip's test base plate, be used for spraying the printing ink that discolours on electric leakage LED chip, be connected with the power and to the some survey equipment of electric leakage LED chip let in reverse voltage, the printing ink that discolours can demonstrate different colours under different temperatures;

after the reverse voltage is applied to the leakage LED chip, the color of the leakage point is different from that of the non-leakage point.

As an improvement of the scheme, the thickness of the color-changing printing ink sprayed on the leakage LED chip is 30-100 mu m.

As an improvement of the scheme, the color-changing ink displays different colors in different temperature intervals, wherein the temperature of the color-changing ink is 5-10 ℃ in one temperature interval.

As an improvement of the scheme, the point measurement equipment comprises a probe, and the probe is connected to an electrode of the electric leakage LED chip so as to apply reverse voltage to the electric leakage LED chip.

As an improvement of the scheme, the test substrate is provided with a plurality of areas arranged in a matrix, each area is mutually independent, and each area is provided with one leakage LED chip.

As an improvement of the scheme, the LED leakage detection device further comprises a photographing device or an amplifying device, so that the position of the leakage point of the leakage LED chip can be determined by photographing and imaging the leakage LED chip.

Implement the utility model discloses, following beneficial effect has:

the utility model discloses a system for test electric leakage LED chip earth leakage point fast simple structure lets in reverse voltage to electric leakage LED chip through the current some check out test set of chip factory to the spraying ink that discolours on electric leakage LED chip, utilize electric leakage point resistance height, under the condition that lets in reverse voltage, the principle of the high non-electric leakage point's of temperature of electric leakage point temperature, under the condition that does not increase new equipment, the short-term test goes out electric leakage LED chip's electric leakage point position, and is with low costs, and the operation of being convenient for.

Drawings

Fig. 1 is a schematic diagram of the system for rapidly testing the leakage point of the leakage LED chip of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, the utility model provides a pair of a system for be used for quick test electric leakage LED chip electric leakage point, including power 1, test substrate 2, the printing ink that discolours 3 and some check out test set 4.

Specifically, electric leakage LED chip 5 is placed on test substrate 2, in order to improve efficiency of software testing, the utility model discloses a test substrate 2 is equipped with a plurality of matrix arrangement's regional 21, and every regional 21 mutual independence, electric leakage LED chip 5 is placed to every regional 21.

Further, each independent area 21 is correspondingly provided with a number so as to manage the leakage LED chips.

It should be noted that the test substrate 2 of the present invention does not have a conductive function as a carrier of the leakage LED chip 5. If the utility model discloses a test substrate 2 is conductive substrate, then influences the electric leakage point test of electric leakage LED chip 5. Preferably, the test substrate 2 is an aluminum substrate or a ceramic substrate.

The utility model discloses a 3 spraying of printing ink that discolour are on electric leakage LED chip 5 for demonstrate electric leakage LED chip 5's electric leakage point. Because the resistance of the leakage point of the leakage LED chip is larger than that of the non-leakage point, after the reverse voltage is introduced to the leakage LED chip 5, the current of the leakage point is larger than that of other non-leakage points, so that the temperature of the leakage point is larger than that of the non-leakage points, and the position of the leakage point is found out according to different colors.

The color that is different from the non-leakage point in order to distinguish the leakage point, the utility model discloses a color-changing printing ink can demonstrate different colours under the temperature of difference. Specifically, the utility model discloses a color-changing printing ink demonstrates different colours in the temperature interval of difference. In order to guarantee that the colour changes obviously, and the colour of electric leakage point can obviously be distinguished with the colour of non-electric leakage point, the utility model discloses a printing ink that discolours uses 5 ~ 10 ℃ as a temperature interval. Specifically, the utility model discloses the condition of discolouing of the printing ink that discolours is as shown in the following table:

temperature (. degree.C.)	-5	0	5	10	16	21	31
								Colour(s)	Scarlet color	Rose color	Peach red	Zhuhong (Red wine)	Orange red	Bao lan	Dark blue
Temperature (. degree.C.)	33	38	43	45	50	65	70
								Colour(s)	Sea blue	Grass green	Blackish green	Middle green	Peacock green	Golden yellow	Black colour

The color-changing ink is temperature-sensitive color-changing ink with the model of DAS-WB, and is made by DiOrsyn waterborne coating Co.

It should be noted that the thickness of the color-changing ink sprayed on the leaky LED chip has an important influence on the test effect, and if the thickness of the color-changing ink is too thin, the color change is not obvious, and it is difficult to find out a leaky point; if the thickness of the color-changing ink is too large, the position of the leak point is difficult to be observed. Preferably, the thickness of the color-changing ink sprayed on the leaky LED chip is 30-100 mu m. Preferably, the thickness of the color-changing printing ink sprayed on the leakage LED chip is 40-80 mu m. The thickness ranges only aim at the color-changing ink and the color-changing ink of different types, and the sprayed thickness is different.

In order to reduce cost, this application lets in reverse voltage to electric leakage LED chip through the current some check out test set of chip factory, when not increasing the cost, can accomplish electric leakage LED chip's electric leakage point fast and detect.

The existing point testing equipment is only used for testing parameters such as wavelength, brightness and voltage of the LED chip and testing whether the LED chip leaks electricity or not, and cannot be directly used for detecting the position of a leakage point of the leakage LED chip.

The spot measurement device 4 comprises a probe 41, wherein the probe 41 is connected to an electrode of the leakage LED chip 5 to apply a reverse voltage to the leakage LED chip 5. Since the LED chip has a small size, if other devices are used to contact the electrodes of the LED chip, the chip is easily damaged. The existing point testing device is originally used for testing the LED chip, so that the leakage LED chip cannot be damaged.

The utility model discloses be connected point survey equipment 4 with external power 1 to the realization lets in reverse voltage to electric leakage LED chip 5. It should be noted that only when a reverse voltage is applied to the leakage LED chip, the temperature of the leakage point can be higher than the temperatures of other positions of the chip, so as to find out the position of the leakage point according to the difference of colors. Because the resistance of the leakage point is larger than that of the non-leakage point, when the reverse voltage is applied to the leakage LED chip 5, the current of the leakage point is larger than that of the other non-leakage points, and thus the temperature of the leakage point is larger than that of the non-leakage point.

It should be noted that the reverse voltage is only required to be applied to the diode; when the applied reverse voltage does not exceed a certain range, the current passing through the diode is reverse current formed by the drift motion of minority carriers.

The utility model discloses the reverse voltage to electric leakage LED chip let in can not too big also can not the undersize, if reverse voltage is too big, then electric leakage LED chip's electric current is too big, can destroy, burn out electric leakage LED chip even to can not find the electric leakage point. If the reverse voltage is too small, the current of the leakage LED chip is too small, the temperature change is not obvious, and a leakage point cannot be found. Preferably, the utility model discloses let in 5 ~ 10V's reverse voltage to electric leakage LED chip. Preferably, a reverse voltage of 10V is applied to the leakage LED chip.

Specifically, the utility model discloses after letting in 5 ~ 10V's reverse voltage to electric leakage LED chip to the reverse current IR of control electric leakage LED chip is less than 10 mu A. After the reverse voltage is applied, if the reverse current IR of the leaky LED chip is greater than 10 μ a, the leaky LED chip is destroyed or even burned out due to an excessive current, so that a leaky point cannot be found.

Due to the small size of the LED chip, temperature changes are essentially instantaneous with stable power supply. Namely, after the reverse voltage is introduced into the leakage LED chip, the leakage LED chip basically generates corresponding temperature change instantly. The color-changing ink can completely show corresponding color change within 5 to 10 minutes.

Because the size of LED chip is very little, the naked eye is difficult to observe and obtains, the utility model discloses a photographing equipment or amplification equipment are shot the formation of image and are confirmed the position of electric leakage LED chip earth leakage point to electric leakage LED chip.

It should be noted that the present spot measuring device 4 itself is provided with the imaging device 42, the present invention can utilize the imaging device 42 of the spot measuring device itself to take a picture and form an image, and can also adopt the present camera device, the present invention is not limited specifically.

The above disclosure is only a preferred embodiment of the present invention, and certainly should not be taken as limiting the scope of the invention, which is defined by the claims and their equivalents.

Claims

1. A system for rapidly testing electric leakage points of an electric leakage LED chip is characterized by comprising a power supply, a test substrate for placing the electric leakage LED chip, color-changing ink for spraying on the electric leakage LED chip, and a point testing device which is connected with the power supply and is used for applying reverse voltage to the electric leakage LED chip, wherein the color-changing ink can show different colors at different temperatures;

2. The system for rapidly testing the electric leakage point of the electric leakage LED chip as claimed in claim 1, wherein the thickness of the color-changing ink sprayed on the electric leakage LED chip is 30-100 μm.

3. The system for rapidly testing the leakage point of the leakage LED chip as claimed in claim 1, wherein the color-changing ink shows different colors in different temperature intervals, and the temperature interval of the color-changing ink is 5-10 ℃.

4. The system for rapidly testing the leakage point of the leaky LED chip as claimed in claim 1, wherein said point testing device includes a probe connected to an electrode of the leaky LED chip for applying a reverse voltage to the leaky LED chip.

5. The system for rapidly testing the leakage point of the leaky LED chip as claimed in claim 1, wherein said test substrate is provided with a plurality of regions arranged in a matrix, each region being independent of each other, and each region being configured to hold a leaky LED chip.

6. The system for rapidly testing the leakage point of the leaky LED chip as claimed in claim 1, further comprising a camera device or an amplifier device for taking a picture of the leaky LED chip to determine the position of the leakage point of the leaky LED chip.