Understanding Photoluminescent Properties of Silicon Based Nanosheets

We present a study of photoluminescence in silicon nanosheets, finding strong evidence that emission of light is dependent on surface passivation and temperature. These findings have implications in optoelectronic devices and understanding the affects that nanosheet surface bound molecules have on photoluminescence. Our analysis shows that the average lifetime of the emission is well within the nano-second scale and that the temperature directly affects the overall intensity of emission. Our kinetic modeling of the photoluminescence of different silicon nanosheets was done to investigate how the difference in structure changes the nature of photoluminescent decay. Temperature and molecules bound to the surface of the nanosheets causes the electronic environment on the surface to change. These changes affect how easily the electrons can be excited by light, when those electrons relax they re-emit light. Understanding how this excitation and relaxation occurs is very useful for applications in circuits and computers. While computers are faster than ever before there are limiting issues that come from heat that is generated from the materials used in the electronic components. The benefit that silicon nanosheets would lend to computing is that instead of electric conductors, like copper, which generate heat, we would be able to use light to carry information and further increase computing power.