Manufacturing method for improving packaging and positioning precision of two-piece type frame

Abstract

The invention provides a manufacturing method for improving the packaging and positioning precision of a two-piece type frame. The method comprises the steps of a, positioning a lower frame (15); b, coating a proper amount of soldering paste on the carrying table of the lower frame (15); c, attaching a chip to the lower frame (15); d, coating a proper amount of tin paste on the carrying table of an upper frame (14); e, covering the upper frame (14) onto the lower frame (15); f, carrying out high-temperature welding on the upper frame and the lower frame; g, encapsulating the frames by using resin; h, rib-cutting and forming. During the resin encapsulation step, an upper positioning hole and a lower positioning hole are unequal in diameter, so that the dislocation between the frames and anencapsulation mold is prevented from further expanding. The positioning precision between the frames and the encapsulation mold in the resin encapsulation step is effectively improved. The damage to the frames caused by the encapsulation mold in the resin encapsulation step is effectively avoided. The high-precision product appearance control is achieved. As a result, the condition that the left and right pins of a product are inconsistent in length due to the large positioning deviation in the rib-cutting and forming step is avoided.

Description

technical field [0001] The invention relates to a manufacturing method for improving the positioning accuracy of a two-piece frame package. Background technique [0002] With the continuous expansion of the application requirements of electronic components in various industries and the continuous reduction of procurement costs, some small SMD electronic components are developing towards high efficiency and low cost. Among them, the use of high-density, matrix frame is becoming an industry trend, especially the upper and lower two-piece combination form is more prominent in cost saving, and has been widely accepted by the industry. [0003] However, in the traditional two-piece frame design, the positioning holes of the upper and lower frames are equal in diameter, which has the problems of positioning accuracy and positioning error accumulation: in the welding process of the first step, due to the hole making Due to the control accuracy and the gap margin of the positioning...

AI Technical Summary

Problems solved by technology

[0003] However, in the traditional two-piece frame design, the positioning holes of the upper and lower frames are equal in diameter, which has the problems of positioning accuracy and positioning error accumulation: in the welding process of the first step, due to the hole making Due to the control accuracy and the gap margin of the positioning pin, the misalignment of the upper and lower frames after welding can only be controlled within ≤0.04mm

For the same reason, due to the dislocation of the upper and lower frames caused by the chip welding step, and after high-temperature welding, the upper and lower frames can no longer move relative to each other. If the hole has been misaligned) to locate, the phenomenon of further expansion of the positioning deviation will inevitably occur, resulting in different lengths of the pins of the product after cutting and forming, that is, the so-called "long and short pins".

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