Highly reliable double-sided heterogeneous composite electrode chip capacitor

Abstract

The present invention provides a highly reliable double-sided heterogeneous composite electrode chip capacitor. The chip capacitor comprises a capacitor ceramic substrate, a surface electrode and a bottom electrode. The surface electrode and the bottom electrode are respectively disposed on two surfaces of the capacitor ceramic substrate. The surface electrode is a silver layer, and the bottom electrode is formed by laminating a titanium tungsten layer, a copper layer and a gold layer on the capacitor ceramic substrate from the inside to the outside. The invention also relates to a method forpreparing the high reliability double-sided heterogeneous composite electrode chip capacitor. The chip capacitor is suitable for requirements of the reflow soldering process, the surface is suitable for routing bonding, and the chip capacitor has the advantages of good bonding effects, high temperature resistance, high reliability and high stability.

Description

technical field [0001] The invention relates to the technical field of electronic components, in particular to a highly reliable double-sided heterogeneous composite electrode chip capacitor and a preparation method thereof. Background technique [0002] Single-layer ceramic chip capacitors (Single-layer capacitors, SLC) have the advantages of small size, thin thickness, low equivalent series resistance, low loss, etc., and their applicable frequency can reach 100MHz-100GHz. occasions have broad application prospects. Single-layer ceramic chip capacitors are widely used in microwave communication lines, microwave power amplifiers, modules (Bluetooth modules, integrated circuit external components, hybrid integrated circuit modules, radio microwave communication modules), oscillation circuits, timing delay circuits, coupling circuits, suppression High-frequency noise circuits, RF bypass and microwave integrated circuits are high-reliability and high-stability products for mi...

AI Technical Summary

Problems solved by technology

[0006] However, the chip capacitors with double-sided silver electrodes have the following problems in the bonding process and actual use of solder paste reflow soldering: the silver surface electrodes are suitable for bonding with aluminum wires, copper wires or gold wires, and the soldering The effect is good, but when the silver bottom electrode is welded on the circuit board by solder paste reflow soldering technology, there is a silver eating phenomenon (silver migration). A slight silver eating phenomenon will cause a sudden change in the electrical performance of the chip and a decrease in reliability, and the silver eating phenomenon is serious. At this time, there is no silver attached to the bottom of the chip, which exposes the ceramic body, causing the chip to separate from the circuit board after soldering, which directly leads to product failure. In addition, when silver and tin are welded together, a tin-silver alloy will be formed, resulting in a change in the electrode performance of the chip.

Images