Abstract: A light emitting device (10) incorporates a layer (12) of porous silicon of low dimensionality surmounted by a discontinuous layer of silver in the form of discrete islands (20). A digitated electrode (13) is connected to the islands (20). The islands (20) have diameters in the range 5 nm to 20 nm and spacings in the range 10 nm to 50 nm, and they form a Schottky diode structure on the silicon (12). Under electrical bias, the diode structure conducts and light is generated. The device (10) is produced by vacuum deposition of silver onto a silicon wafer at a temperature which provides for the silver to separate into individual balls (20). The wafer is then anodized to produce a porous layer incorporating columns of silicon and silicon dioxide surmounted by respective silver islands (20). Each silver island (20) protects the underlying silicon (21) from the anodizing medium, and subsequently provides an electrical contact to the silicon.