FOSEM Co., Ltd. was established in November 2017 to commercialize optical devices such as laser diodes and photodetectors based on compound semiconductors, including GaAs and InP.
Unlike single-crystal semiconductors such as Si and Ge, compound semiconductors are crystalline materials formed by combining two or more different elements. By controlling their composition ratios, they can form various types of bandgaps.
In particular, direct-bandgap compound semiconductors offer the advantage of enabling optical devices across a wide range of wavelengths, from visible blue, green, and red light to invisible ultraviolet and infrared regions.

FOSEM’s CEO and CTO are experts with over 18 years and 12 years of experience, respectively, in the field, bringing extensive expertise and technical knowledge.
FOSEM possesses knowledge and manufacturing technologies for 850nm VCSELs, which are used in short-distance optical communications such as data centers, as well as GaAs PIN Photo Diodes capable of receiving these signals. The company also has technologies for InGaAs PIN PDs, which are used for medium-distance optical communications in the 1300–1550nm wavelength range, and InGaAs APDs, which are used for long-distance optical communications.
In addition, FOSEM has secured development technology for 20W-class high-power laser diode chips capable of continuous operation in the 970nm wavelength band.

High-power laser diodes and avalanche photodiodes are key components of LiDAR sensors, which serve as core sensor modules for autonomous vehicles and are foundational technologies of the Fourth Industrial Revolution.
To commercialize these products, all members of FOSEM are dedicated to moving forward with passion and commitment.