SMD-type IRM high shielding structure and making process thereof

Abstract

The invention belongs to the technical field of infrared signal receiving and particularly relates to a SMD-type IRM high shielding structure which comprises a PCB (printed circuit board). A pluralityof on holes are penetratingly formed in the PCB, a copper column is plugged in each on hole, a PD wafer is arranged on the front of the PCB, an IC chip is arranged on the back of the PCB, and one endof each copper column is connected onto the PD wafer through a bonding wire while the other end of the same is connected onto the IC chip through a bonding wire; packaging glue is cured on each of two sides of the PCB, and the PD wafer and the IC chip are arranged in the packaging glue on the two sides of the PCB. The SMD-type IRM high shielding structure has the advantages that material and process cost of an inner shielding cover or an outer shielding cover is saved while light interference is blocked; the making process is simplified, multiple processes are reduced when compared with plug-in products and SMD support-type products, and high-cost electrotinning procedures causing wastewater and waste gas pollution are reduced; compared with SMD-type PCB products, assembly difficulty andlabor cost of the outer shielding cover are reduced.

Description

technical field [0001] The invention belongs to the technical field of infrared signal reception, and in particular relates to a patch type IRM high shielding structure and a manufacturing process thereof. Background technique [0002] IRM is an infrared receiving module, which has a photosensitive PD chip inside, and a processing and amplifying IC chip in series, which can receive 940nm infrared light, and process, rectify, decode, and amplify the signal using infrared light as a carrier wave, and send The optical signal is converted into an electrical parameter model. Because the processing and amplification of the IC chip will also be interfered by other light in the external natural light, the packaging colloid is used in black epoxy glue. The black colorant component can filter out visible light and part of infrared light, up to 860nm Infrared light below, but because the pass rate of filtered red light is about 80%, there are still high-wavelength spectra in sunlight, ...

AI Technical Summary

Problems solved by technology

The patch type is divided into bracket type and PCB type. The patch type bracket type copper or iron bracket is also a bent inner shield structure; and the IRM type PCB structure is designed with an external iron shell as a shield cover. All three types of packaging have the problems of complex production process, low yield and high cost

[0004] First of all, the IRM with bracket bending structure is limited by equipment, the product density is generally 20PCS conjoined, up to 40PCS conjoined, the production efficiency is extremely low

[0005] The UPH of a single production line is only 5-10K / h, and there are many production processes for brackets, including die bonding, wire bonding, bending shields, sealing, removing glue, laser coding, water jetting (or sandblasting), electroplating, and rib cutting , Bottom rib cutting, testing, full corner cutting and packaging require 13 procedures, especially electroplating tin is a heavy polluting industry. At present, environmental protection requirements are getting higher and higher, electroplating factories are gradually decreasing, and later costs will increase, and mistakes in one process will result. Affect the overall yield

[0006] SMD stent packaging is the same as the above-mentioned packaging production process, only the density is increased, but the maximum density is between 80-120pcs, the improved efficiency is also very small, but the cost of the stent is increased by 2-3 times, the overall cost is higher than the plug-in IRM

[0007] SMD PCB packaging reduces the number of processes on the finished package, including die bonding, wire bonding, glue sealing, cutting, testing, iron casing (manual and automatic, but the efficiency is very low) and tape, a total of 7 processes, but Installing an external iron shell requires additional costs, and a soldering iron is required to weld the iron shell and the IRM product to prevent it from falling off. At the same time, the contact time of the high temperature (about 380°C) during welding needs to be controlled within 10s, which further increases the difficulty of production.

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