Formex V01 is a formic-acid reflow lead-free solder paste engineered exclusively for formic-acid soldering processes. Formic-acid soldering is typically applied for preform solder foil bonding without flux. With no flux involved, there are no flux residues after soldering and no cleaning is required. Nevertheless, preform solder foils are non-tacky, which necessitates extensive tooling to position components or chips. Especially for products featuring numerous small pads, such as surface-mount devices and terminals, positioning of foils and components poses significant challenges to manufacturing processes.

To address the above challenges, Huaqing has developed Formex V01, a lead-free solder paste for formic-acid soldering. Like conventional solder pastes, it can be printed or dispensed, and it possesses tackiness to facilitate easy positioning of components and chips. Unlike standard solder pastes, most of the flux in Formex V01 volatilizes during soldering. As a result, it leaves no flux residues just like preform solder foils after bonding. No post-soldering cleaning is needed, and it will not interfere with subsequent processes such as wire bonding.

Formex V01 can be used to solder chips, surface-mount devices, terminals and other components under formic-acid atmosphere. It can also be applied together with preform solder foils. When used in combination with preforms, standard thermal profiles for preform soldering are applicable.

Core Advantages

• Zero or ultra-low flux residue 

• Excellent printability and dispensability 

• Wide process window, compatible with various thermal profiles

• Suitable for common metallic interfaces including copper, nickel, silver and gold 

• Minimal spattering and solder balls 

• No cleaning required after soldering