Study on the weldability of stainless steel fabricated by powder metallurgy and metal injection molding for optoelectronic packages

To reduce the cost of optoelectronic modules, powder metallurgy (PM) and metal injection molding (MIM) are employed to fabricate metal housings for optoelectronic packages. During the laser welding of PM steel, the rising gas pressure pushes the molten metal out of the welding regions, resulting in weak and unstable joints. Metal parts fabricated by the MIM method provide good weldability, shape complexity, low cost, and long-term reliability. By using the MIM method, defect-free welding joints and postwelding-shifts of less than 1 μm are achieved, and the optoelectronic packages are reliable. Employment of MIM not only gives optoelectronic module designers more design flexibility due to the advantage of shape complexity, but also makes low-cost triple-directional optoelectronic modules realizable.