A Partial Potting Process Method for Preventing Device Leakage

Abstract

The invention discloses a local plotting technique for preventing the current leakage of a device. The technique comprises the steps: setting a fence at an outer edge of the device; setting a lead of an integrated structure on the device; employing the local plotting silicon rubber technique for setting a plotting material between the lead and the fence; carrying out the plotting after vacuum processing, and carrying out the room temperature curing for completing the protection technological processing. The technique meets the requirements of large-mass and multi-lead secondary reinforcement. The conventional reinforcement measure of QFP and SOP packaging devices is just a measure of four-corner dipping and underlay reinforcement glue. For the QFP and SOP packaging devices with the interval being less than 0.55mm, the method can achieve the secondary reinforcement after protection, is suitable for the mechanical conditions in a better way, improves the application reliability of the devices, reduces the rejection rate of the devices, and saves the cost.

Description

technical field [0001] The invention belongs to the technical field of safety and reliability of electronic components, and in particular relates to a partial potting process method for preventing device leakage. Background technique [0002] Generally, in the fields of aerospace and military industry, the three-defense protection of printed circuit board assemblies of electronic products mainly adopts the process of coating protective coatings. For most products, this method can meet the general requirements of the product. However, for some domestic devices, the lead-out spacing is less than 0.5mm, and the model tasks using this type of device have strict requirements on water vapor and humidity environments, so the above method is insufficient. In QJ3259 "Technical Requirements for Protective Coating of Aerospace Electronic Products", the requirement for coating is "30μm~50μm". Such a thick coating is not enough to overcome the influence of water vapor intrusion for sen...

AI Technical Summary

Problems solved by technology

Such a thick coating is not enough to overcome the influence of water vapor intrusion for sensitive devices and harsh hot and humid environments, resulting in problems such as insulation drop and leakage between leads with too small pitch, such as figure 1 As shown, direct three-proof spraying, and the minimum spacing between the lead wires of this type of device is less than 0.5mm, and the leakage between the leads will be caused by the increase of humidity in the later test

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