HAMAMATSU realized MSM (Metal-Semiconductor-Metal) photodetector having ultrafast response. The GaAs MSM Photodetector G4176 features 30 ps response time for both rise and fall while keeping a low dark current (100 pA at Ta-25 °C). The rise time of the InGaAs MSM Photodetector G7096 is 40ps. Symmetrical and interdigital Schottky contacts are fabricated at the sensitive area, whose size can be larger than other kinds of fast response photodetectors. This makes easier to set up with optics. Therefore, MSM photodetectors are suited for measurements of optical high-speed waveform and optical communications. There is no electrical polarity in MSM photodetectirs, that is, both polarities of a bias voltage are available, and the polarity of an output signal depends on its connection. Two kinds of packages are prepared for each MSM photodetector. The package of G4176 & G7096 is a coaxial metal type (patent : Japan 2070802), which is easy to connect with an electrical SMA-connector. That of G4176-01 & G7096-01 is a TO-18, which is very common. An optical fiber or connector input types are available as a custom option. Contact your local representative for more information.