An integral vertical cavity surface emitting laser (VCSEL) and power
monitor assembly. The assembly is beneficially fabricated by
anisotropically etching a silicon substrate having substantially flat top
and bottom surfaces to form a cavity defined by an inwardly sloping wall
that extends through the silicon substrate, beneficially to a membrane. A
photodetector (light sensor) is formed adjacent the cavity (such as on a
membrane), and a VCSEL is attached to the silicon substrate such that
light from the VCSEL irradiates the photodetector. Beneficially, the
photodetector is a metal-semiconductor-metal photodetector. An optical
element (a lens) and the end of an optical fiber are beneficially located
in the cavity. The optical element couples light that passes through the
photodetector into the optical fiber.