Channel glass waveguide detectors with grafted GaAs film in embedded configuration

Embedded metal-semiconductor-metal photodetectors have been fabricated by grafting a 250 nm thick GaAs layer within the core of glass channel waveguides. Using this new configuration, edge, rather than vertical, coupling is achieved resulting in a substantial increase in the absorption coefficient and providing a protective layer for the detector. Absorption coefficients of 37.8 cm−1 and responsivities of 0.06 A/W for 50 μn long detectors have been measured at λ = 633 nm.