CW/QCW (Continuous Wave/Quasi-Continuous Wave) laser diode vertical stacks are high-power semiconductor laser devices that consist of multiple laser diodes integrated into a single package in a vertical configuration. These devices are commonly used in materials processing, medical equipment, printing, and imaging applications where high output power and beam quality are required.
Each laser diode in a vertical stack typically contains several individual laser emitters, and the total output power of the device can range from a few watts to hundreds of watts, depending on the number of laser diodes and the design of the device.
The fabrication process for CW/QCW laser diode vertical stacks is similar to that of other laser diode chips and modules. It involves epitaxial growth of the active and cladding layers on a substrate, followed by lithography and etching to define the device structure. The individual laser diodes are then formed by cleaving or dicing the device into smaller pieces, each containing one or more laser emitters.
The orientation of the laser diodes in a vertical stack allows for efficient cooling of the device, as the heat generated by the high power output can be dissipated through a larger surface area. In addition, the vertical configuration enables easy coupling of the output light into an optical fiber or other delivery system.
CW/QCW laser diode vertical stacks can be designed to emit light in a continuous wave (CW) mode or in a quasi-continuous wave (QCW) mode. In CW mode, the laser diodes emit a continuous stream of light, while in QCW mode, the laser diodes emit short bursts of high-intensity light with a duty cycle of typically less than 50%.