A light-emitting diode packaging structure and packaging method

Abstract

The present application provides an LED encapsulation structure and encapsulation method. The LED encapsulation structure comprises: a heat dissipation substrate, an LED chip, a first fluorescent powder adhesive layer, a second fluorescent powder adhesive layer, a first buffer layer, a first light filter layer, a second buffer layer, a second light filter layer and a lens layer, wherein the LED chip is fixed on the heat dissipation substrate, the first light filter layer and the first buffer layer coat the LED chip, the first fluorescent powder adhesive layer coats the first light filter layer and the first buffer layer, and the second light filter layer, the second buffer layer and the second fluorescent powder adhesive layer successively coat the first fluorescent powder adhesive layer, thereby forming a sandwiched optical structure. In the LED encapsulation structure and encapsulation method provided in the present application, buffer layers and light filter layers are used. Thus, the direct contact between a chip and fluorescent powder is prevented, thereby solving the problem of the decrease of the quantum efficiency of the fluorescent powder due to a high temperature; and the problem of the decrease of the quantum efficiency of the fluorescent powder caused by mutual absorption of fluorescent powder layers is also prevented.

Description

technical field [0001] The invention relates to white light LED packaging technology and belongs to the technical field of semiconductors. Background technique [0002] Compared with traditional lighting sources, white LEDs have the advantages of low energy consumption, long life, small size, fast response, and no pollution. They are widely used in liquid crystal display backlight applications, mobile phones, signal lights, and solid-state lighting. At present, the way to realize LED white light is mainly realized by multi-chip combination or single-chip matching phosphor. Among them, the realization of white light LED by phosphor matching method has the advantages of simple preparation method, low cost, and easy industrialization, and has been widely used in the preparation of white light LED. The main ways to achieve white light by phosphor matching method are: blue chip + yellow phosphor or blue chip + green phosphor or yellow phosphor + red phosphor or ultraviolet chip ...

AI Technical Summary

Problems solved by technology

Among them, the blue light chip + yellow phosphor powder method cannot meet the requirements of high color rendering and high light efficiency at the same time because the color rendering index is too low; therefore, at present, two or more phosphor powders are usually used to achieve white light when a single chip is matched with phosphor powder.

Based on the above scheme, there must be overlapping coupling between phosphor spectra. In this case, mutual absorption will occur between phosphors. For example, part of the light of green phosphor is likely to be reabsorbed by red phosphor, resulting in a decrease in light efficiency.

In addition, due to the large difference in thermal matching between the LED chip and the phosphor, the quantum efficiency of the phosphor will inevitably decrease under high temperature conditions, which will further affect the light efficiency of the LED package.

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