Conducting slurry for direct laser writing

Abstract

The conducting slurry for direct laser writing includes adhesive phase, conducting phase, organic solvent and organic filming matter, and the adhesive phase moltable glass powder with softening temperature of 200-450 deg.c and meltable metal powder of smelting point of 180-300 deg.c and accounting for 25-100 wt% of the total adhesive phase. The conducting slurry of the present invention is used in direct laser writing to produce conducting wire and the conducting wire has base board combining strength of about 5 MPa and resistivity smaller than 10 omega cm. The laser used is small-power continuous or quasi-continuous laser, the wiring speed is up to 20 mm / s, and the wire witdth is adjustable in 0.01-2 mm.

Description

technical field [0001] The invention relates to a conductive paste, in particular to a conductive paste for laser direct writing. Background technique [0002] With the development of electronic and electrical products in the direction of ultra-large-scale integration, digitalization, lightweight, small batches, and diversification, traditional printed circuit board (PCB: Printed Circuit Board) and thick film circuit manufacturing methods include photochemical methods and Stencil (or silk screen) printing method can not meet the requirements more and more. Specifically reflected in: there are many manufacturing processes, which easily lead to large errors for high-density and high-precision printed circuit boards; the minimum line width and line spacing are greatly restricted; many conductive materials are removed by corrosion, resulting in a lot of waste of precious metals; electroplating , Corrosion and other processes using the solution will cause great pollution to the ...

AI Technical Summary

Problems solved by technology

The softening temperature of such conductive paste is too high for laser direct writing, which greatly limits the wiring speed and increases the damage to the substrate surface. It is easy to cause the substrate to break due to the excessive temperature difference between the substrate surface and the core.

Oxide bonding paste needs to be sintered at a temperature close to the melting point of the metal to maintain high adhesion strength, so it has the same disadvantages as high softening temperature glass bonding paste

Organic conductive paste, also known as conductive adhesive, uses the principle of resin curing to provide adhesion, and is more suitable for organic substrates, such as epoxy resin substrates, phenolic resin substrates, etc. The curing temperature is very low, but the use temperature is also very low Generally, when used at a temperature higher than 200°C, thermal decomposition will gradually occur; and the bonding strength of the resin on substrates such as glass and ceramics is not very high

So organic conductive paste is not suitable for glass, ceramic or semiconductor substrates