Silicon microcavity light emitting devices

Abstract We report the optical and electrical properties of all-silicon microcavity light emitting devices (LEDs) made of a thin, high-porosity porous silicon active layer sandwiched between two Bragg reflectors made of several pairs of low index/high index of refraction porous silicon layers of lower porosities. The design and passivation of the structures are discussed. The electroluminescent properties are examined in detail, including the strong narrowing of the spectrum, the widely tunable peak position, the emission directionality, the power efficiency, and the stability. The possible uses of these silicon microcavity LEDs are considered and the challenges that need to be met in terms of materials science and device design are examined.