In the ideal situation,a single photon is produced by the emission of quantum dot single photon source.A quantum dot single photon emission device is achieved when we combine the self-organized growth method with optical microcavity structure on patterned substrate.When we adopt a pyramid-shaped substrate to prepare quantum dots,quantum dot growth with a high degree site-controlled is achieved,and single photon source quantum dots are easy to prepare and isolate.The problem of multiple quantum dots occupyin...