Lid for functional part and process for producing the same

Abstract

The invention provides a solder layer as a substitute for a high-temperature solder which bonds a functional-part package to a lid and has a solidus temperature of 250 DEG C or higher. It is obtained by: applying a solder paste obtained by mixing a copper-based metal powder having a solidus temperature of 400 DEG C or higher with a tin-based solder powder to a lid made of a material difficult to solder and plated beforehand with a material having excellent solderability; and heating the solder past applied. The solder layer formed on the deposit comprises the copper-based metal powder, an intermetallic compound of Cu6Sn5, and the lead-free solder. This solder layer functions as a high-temperature solder because the intermetallic compound is bonded to the material difficult to solder and particles of the intermetallic compound are connected to one another. Although high-temperature solders have poor soldering properties, this problem can be avoided with the solder layer.

Description

technical field [0001] The present invention relates to a cap for hermetically sealing a package of a functional component, particularly a functional component in which an element is accommodated, and a method for manufacturing the same. Background technique [0002] Functional components such as crystal oscillators, SAW filters, and sensors are housed in a package, and the package is covered with a cap to make it airtight. In order to seal this package in an airtight state with a lid, adhesive, brazing material, and solder are used, but solder is preferably used in terms of ease of sealing work and economical efficiency of materials. The package is made of ceramics such as alumina, aluminum nitride, mullite, glass ceramics, etc., and cannot be directly joined by solder. In order to join such a package to a lid, the joint portion of the package is metallized with tungsten, molybdenum, etc., and then plated with Ag-Pt, Ni, Au, etc. that can be soldered. [0003] On the othe...

AI Technical Summary

Problems solved by technology

[0019] However, Cu-mixed high-temperature solder has poorer solderability than conventional high-temperature solders with a main component of Pb

In addition, Cu-mixed high-temperature solder pastes are problematic in the packaging of functional parts and soldering of covers

[0020] Therefore, even if a Cu-mixed high-temperature solder is used for the soldering of the package and the cover of the functional part, the above-mentioned solder paste for the Cu-mixed high-temperature solder cannot join the cover with poor solderability. Is there a problem in the soldering of the package with the functional part

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