Abstract: A method of fabricating quantum dot structures and devices including the steps of: (i) forming a quantum well membrane on a substrate; (ii) on the quantum well membrane forming a masking layer including a plurality of dot-shaped mask regions which protect the underlying quantum well membrane; (iii) using thermal etching to evaporate portions of the quantum well membrane that are not protected by the dotted mask regions of the masking layer so as to form a plurality of quantum dots; and (iv) after thermal etching, covering the plurality of quantum dots with a layer of material having an energy gap that is greater than the energy gap of the quantum well membrane. The quantum dot produced by this invention is found to generate ten times more illumination than the prior art when measured by photoluminescence.