Ceramic Capacitor with Predeposited Solder

Ceramic Capacitor with Predeposited Solder

Predeposited AuSn capacitors gain in popularity for semiconductor products as communication speeds increase.

Wireless communication continues to develop rapidly on a global scale. The 5th generation mobile communication system, known as 5G, is set to be so astonishingly fast. So much so, that downloading videos that took 30 seconds on 4G will be capable of being completed in 3 seconds. Among the semiconductor products that are the key to this acceleration are “AuSn ceramic capacitors”. Switching the method used to mount capacitors on circuit boards from epoxy resin to AuSn solder enables an increase in thermal conductivity and consequently reduced failure rate due to decreased temperature rise during operation.

The Challenge:

Creating a mounting method that eliminates the handling issues surrounding AuSn preforms, the current alternative to epoxy resin.

Conventional die-attach using AuSn solder requires a plate-like preform of AuSn solder to be positions between the single layer ceramic capacitor and the circuit board instead of dispensing epoxy resin. However, because the AuSn preform is very small and ultra-thin, it is difficult to handle and gives rise to the risk of shorting due to misalignment in installation position.

AuSn preform

The Solution:

Development of a “ceramic capacitor with predeposited AuSn” product.

Tecdia developed a metal deposition technique to realize “ceramic capacitors with predeposited AuSn” in which AuSn solder is deposited to the backside of the capacitor at the wafer level. This eliminates the need for discrete AuSn solder preforms to be purchased or handled, improving yields and simplifying the die-attach process.

AuSn Preform Comparison

In addition to solving the handling issues, “ceramic capacitors with predeposited AuSn” contribute to a reduction in cost as the number of parts required for mounting decreases. Moreover, this leads to a reduction in manufacturing processes and effectively shortens product lead time. Although the conventionally used AuSn preforms are 20 to 30 μm thick, our “ceramic capacitor with predeposited AuSn” have an AuSn solder layer that is 10um thick. This reduces restrictions on installation locations and mounting in narrow places becomes possible due to the reduced solder spillage.

The Result:

We have succeeded in creating a component that reduces product lead times by reducing die-attach costs and simplifying manufacturing processes.

Client Information

[Client Industries]
Wireless communication device manufacturers