Device and method for pressure-molding anti-overheating CSP fluorescent membrane

Patent metadata

Field	Value
Publication number	US-10962178-B2
Application number	US-201716349589-A
Country	US
Kind code	B2
Filing date	Dec 1, 2017
Priority date	Nov 11, 2016
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

Disclosed are a device and a method for pressure-molding an anti-overheating CSP fluorescent membrane. The device comprises a frame, a mould pressing device, a force measuring device, a control device and a feeding device; and the mould pressing device comprises an upper pressing mould, an upper clamp, a lower pressing mould, a guide post, an elastic supporting structure, and a lower clamp. As the stage of pressing the elastic supporting structure is added to the course of pressure molding, a mould clamping force of the pressure molding increases in a relatively steady way, and a force impact of a mould clamping device is reduced, thereby easily determining an initial point for maintain temperature of the pressure molding. The present invention effectively prevents overheating caused by long-term and large-area contact between the lower clamp and the heating lower pressing mould, and avoids the process defect of premature melting of the fluorescent membrane due to overheating, thereby greatly improving the product consistency and yield rate of the CSP-package fluorescent membrane in the pressure molding process.

First claim

What is claimed is:

1. A method of a device for pressure-molding an anti-overheating CSP fluorescent membrane, the device including a lower pressing mould heating device ( 7 ), a force measuring device ( 14 ), a feeding device ( 16 ) and a mould pressing device ( 13 ), the mould pressing device ( 13 ) having an upper pressing mould, a lower pressing mould and a lower clamp ( 5 ), the upper pressing mould having an upper pressing mould body ( 1 ) and an upper pressing mould heating device ( 2 ), the lower pressing mould having a lower pressing mould body ( 6 ), the method comprising the steps of:
step 1: starting the upper pressing mould heating device ( 2 ) and the lower pressing mould heating device ( 7 ) to preheat the upper pressing mould body ( 1 ) and the lower pressing mould body ( 6 );
step 2: clamping an LED chip into an upper surface of the lower clamp ( 5 ) and placing a fluorescent membrane above the LED chip at the same time;
step 3: controlling, by the feeding device ( 16 ), only the upper pressing mould to move downward or only the lower pressing mould to move upward, so that the upper pressing mould and the lower pressing mould get close to each other, and measuring, by the force measuring device ( 14 ), a mould clamping force in real time;
step 4: maintaining a mould clamping state, pressurizing the feeding device ( 16 ) until the mould clamping force measured in real time has a second inflection point, warming up the upper pressing mould body ( 1 ) and the lower pressing mould body ( 6 ) simultaneously through the heating devices, and maintaining the temperature and pressure; and
step 5: controlling, by the feeding device ( 16 ), the upper pressing mould and the lower pressing mould to separate, and taking down the moulded LED chip to complete pressure molding.

2. The method for pressure-molding the anti-overheating CSP fluorescent membrane according to claim 1 , wherein in the step 1, the preheating is to preheat and maintain the temperature at 78-82° C.

3. The method for pressure-molding the anti-overheating CSP fluorescent membrane according to claim 1 , wherein in the step 3, a feeding speed for only the upper pressing mould to move downward or only the lower pressing mould to move upward is controlled as 5-10 cm/s.

4. The method for pressure-molding the anti-overheating CSP fluorescent membrane according to claim 1 , wherein the mould clamping force measured by the force measuring device ( 14 ) in real time has two inflection points, and a stage from mould clamping to a first inflection point is an air compressing stage; a stage from the first inflection point to the second inflection point is a stage of pressure-molding an elastic supporting structure; a stage from the second inflection point to the end of pressure molding is a stage of pressure-molding the fluorescent membrane; and the second inflection point is an initial point for warming, and the temperature after warming is a temperature for the fluorescent membrane to melt and flow.

5. The method for pressure-molding the anti-overheating CSP fluorescent membrane according to claim 1 , wherein in the step 4, the pressurizing is to pressurize the pressure to 1000-2000 Pa; the warming is to warm the temperature to 118-122° C.; and the maintaining the temperature and pressure lasts for 2-3 minutes.

Assignees

• Univ South China Tech

Inventors

• Li Zongtao
• Lin Qinghong
• Tang Yong
• Yu Shudong
• Wang Huiyu
• Liang Guanwei
• Lu Longsheng

Classifications

• H10P72/7624

  characterised by the mechanical construction of the susceptor, stage or support · CPC title

• H10H20/0361

  of wavelength conversion means · CPC title

• H10H20/8514 Primary

  characterised by their shape, e.g. plate or foil · CPC title

• H10H20/85

  Packages · CPC title

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title