Packaging structure and preparation method thereof

Abstract

The invention provides a packaging structure and a preparation method thereof. The preparation method comprises the steps: providing a substrate which is provided with a first surface and a second surface which are opposite to each other; and arranging a box dam on the first surface of the base plate, wherein the box dam comprises a lower layer dam body and an upper layer dam body, the lower layer dam body is arranged on the first surface of the base plate, the lower layer dam body is made of metal materials, the lower layer dam body is provided with a top face, an inner side face and an outer side face, and the upper dam body is arranged on the top face of the lower dam body and forms a step structure. A high-temperature sintering step is avoided, so the manufacturing cost is low; by the adoption of the modular design concept, the upper dam body and the lower dam body of various sizes can be manufactured independently through the same technology or different technologies, so that the preparation process of the box dam is more flexible, and the application range is wide; and the lower dam body made of a metal material can provide an inorganic packaging condition, is better in air tightness, can effectively resist UV irradiation, is high in strength, and can improve the stability of the whole packaging structure.

Description

technical field [0001] The present application relates to the technical field of circuit packaging, in particular to a packaging structure and a preparation method thereof. Background technique [0002] Sensors, crystal oscillators, resonators, lasers, camera devices, LED light sources and other devices are generally packaged with ceramic substrates. The commonly used packaging structure is to set a dam on a ceramic substrate with a circuit layer, and set a cover on the dam. The cover plate, the dam and the ceramic substrate form a sealed chamber, which is used to place various chips and other devices. By filling the sealed chamber with packaging glue, inert gas or directly vacuuming, the device is hermetically sealed. . [0003] At present, the dams are roughly divided into three types, 1. ceramic dams, 2. metal dams, and 3. plastic dams. Among them, ceramic dams are generally sintered by LTCC (Low Temperature co-fired ceramics, low temperature co-fired ceramics) technolo...

AI Technical Summary

Problems solved by technology

Among them, ceramic dams are generally sintered by LTCC (Low Temperature co-fired ceramics, low temperature co-fired ceramics) technology, so that the resolution of ceramic dam lines is not high, and the cost of forming through high-temperature sintering is high

There are generally three ways to make metal dams. The first method is that the metal dam is formed by stamping a single metal or alloy, and then the metal dam is bonded to the ceramic substrate. In this method, the metal dam and the ceramic substrate There is an organic connection between them, and the airtightness is not good; the second way is to weld the metal dam on the ceramic substrate through the metal kovar ring, which requires high welding technology, resulting in low product yield and high cost; the third way The first way is to make the dam on the ceramic substrate by electroplating. The width of the dam in this way is limited and the process is more complicated.

Plastic dams (including epoxy resin) are poorly resistant to UV (ultraviolet) radiation and cannot be welded on cover plates

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