A surface mount inductance device and wafer-level manufacturing method thereof

Abstract

The invention relates to a surface-mounted inductance device and a wafer-level manufacturing method thereof, belonging to the field of passive device manufacturing. It includes a substrate (110), more than one layer of metal wiring layers (200) forming the inductance structure of the central inductance coil area, and electrodes (300) in the electrode areas on both sides, and different metal wiring layers (200) are separated by a dielectric Layer through holes (401) are electrically connected, and two layers of metal wiring layer I (210) and metal wiring layer II (220) of the metal wiring layer (200) extend to the electrode areas on both sides, and are respectively equal to the two sides of the electrode area. The electrodes (300) are connected, and the surface protection layer (500) is covered on the surface of the uppermost metal wiring layer (200). The present invention manufactures structures such as inductance and electrodes on the surface of the wafer through the wafer-level rewiring process, and the obtained surface mount inductive device has higher inductance accuracy, thinner thickness, and higher reliability, and can overcome one-sided warping of mounting Defects, to achieve high-density placement.

Description

technical field [0001] The invention relates to a surface-mounted inductance device and a wafer-level manufacturing method thereof, belonging to the field of passive device manufacturing. Background technique [0002] Inductors are essential components in electronic devices. With the miniaturization trend of electronic devices, especially handheld electronic devices such as mobile phones, the size of inductors is getting smaller and smaller. At present, the RF inductor models for wireless communication mainly have 0201 size and 0402 size (imperial system). Among them, the package length of the 0201 size model is between 500 microns and 700 microns, the width is between 250 microns and 350 microns, and the height is 250 microns. Microns to 350 microns; 0402 size models have packages with lengths between 900 microns and 1100 microns, widths between 400 microns and 600 microns, and heights between 450 microns and 550 microns. Traditional inductors are mainly made by multi-laye...

AI Technical Summary

Problems solved by technology

like figure 2 As shown in the figure on the right, as the inductance device continues to shrink, its own weight becomes lighter and lighter. If the wetting force between the two electrodes of the inductance and the solder is unbalanced during the surface mount process, one end of the inductance will warp, resulting in poor assembly. , greatly reducing the assembly yield

In addition, since the solder will climb to the side wall of the electrode, if the two inductors are too close to each other during assembly, solder bridges will easily appear. Therefore, the distance between the two devices needs to be opened when designing the circuit board, which will lose The circuit board area cannot achieve high-density mounting

[0003] In the LTCC process, the metal circuit used to form the inductor coil is formed by printing and sintering. Due to the limitation of the printing process capability, the dimensional accuracy of the metal circuit is not high, and it is impossible to achieve narrow-pitch circuit printing. Therefore, this process is used. Inductors have low precision, usually less than 4nH, the precision can only reach + / -0.3nH, which cannot meet the needs of high-efficiency RF systems

Additionally, if image 3 As shown, the inductor using the LTCC process is usually a multi-layer structure, and the lines are distributed in the entire thickness range of the inductor, so it is difficult to achieve ultra-thin packaging

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