MKS Instruments is a company that provides instruments, subsystems, and process control solutions to measure, power, monitor, and analyze critical parameters of manufacturing processes. It operates through three business segments: Vacuum Solutions Division (VSD), Photonics Solutions Division (PSD), and Materials Solutions Division (MSD). The VSD segment delivers pressure and vacuum control, materials delivery, power, and plasma and reactive gas products. The PSD segment provides a range of instruments, components, and subsystems for semiconductor manufacturing, electronics, packaging, and specialty industrial applications. The MSD segment develops process and manufacturing technologies for advanced surface modification, electroless and electrolytic plating, and surface finishing.