High-brightness ultrathin light semiconductor device

Abstract

LED chip (A) (InGan / GaN) is glued on Die PAD CUP of lead frame by using insulated transparent chip adhesive (E) (UV Cure). Light beam in inverse direction emitted by LED passing through insulated transparent epoxy resin adhesive is reflected back by Die PAD CUP with high reflectivity Ag being coated. Thus, much light-beam is in the direction wanted so as to obtain microminiature LED with higher brightness. Moreover, the invention also reduces stress caused by thermal shock.

Description

Technical field: [0001] The invention belongs to the technical field of semiconductors, and in particular relates to an ultra-small (Small Size) and ultra-thin (Thin Thichness) light-emitting diode. In more detail, it is to directly paste the InGaN / GaN light-emitting diode chip (Chip) on the silver-plated lead frame Die PAD Cup, make full use of the reverse rate of silver, and improve the brightness of the ultra-small package (Package) LED. The invention of the Package structure. Background technique: [0002] Generally speaking, optical semiconductor devices are products that utilize the photoelectric conversion characteristics of semiconductors to transmit photoelectric signals. Optical semiconductor devices are distinguished from light-emitting devices (350nm-990nm) that emit light forward after converting electrical signals into optical signals like light-emitting diodes, and photosensitive devices that receive optical signals and convert them into electrical signals (p...

AI Technical Summary

Problems solved by technology

[0008] The above-mentioned representative surface mount device (Surface Mounting Device) ultra-small light-emitting diode devices generally use thicker printed circuit boards (PCB substrates), and these printed circuit boards (PCB substrates) (J) have relatively low heat resistance , the thermal shock (Stress) that occurs during the production of light-emitting diodes causes thermal deformation of the printed circuit board (PCB substrate) (J), resulting in weakened adhesion between PCB and epoxy resin, so the reliability of such light-emitting diodes is difficult Guaranteed

[0009] In the production of printed circuit boards (PCB substrates), if you want to ensure reliability, first of all, the manufacturing process will become very complicated, which will increase the manufacturing cost

Secondly, it is impossible to realize the thinning and lightening of ultra-small CHIP LED due to the use of thick PCB

In addition, the light inversion rate of the printed circuit board (PCB substrate) is very low, and the inversion rate of gold (Gold) plated on the DIE PAD is not good, so the surface emitting chip (InGaN / GaN LED CHIP) (390nm -470nm) cannot produce products with higher brightness

In addition, the substrates of these PCBs are 100% imported, so the unit price of raw materials is high, and gold (Gold), a precious metal, is used, so the manufacturing cost becomes expensive.

[0010] Also, in practical applications such as mobile phones (Handy Phone), the Souder Reflow process is used to install chip (CHIP) LED optical devices, but the Souder Reflow process is carried out at 220 ° C ~ 320 ° C , and the heat distortion temperature of the PCB substrate is within 220°C, so the SolderRefolw process has brought a fatal thermal shock to the surface mount (SMD) ultra-small light-emitting diode (Chip LED) devices so far, making Gold Wire (A1) ( A2) and AgEpoxy (E2) fall off from the printed circuit board (PCB substrate)

Therefore, the surface mount type (SMD) ultra-small ChipLED device with the latest technology is difficult to guarantee its life.

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