Fabrication of hyperboloid-drum structure for electrically pumped laser of sub-micrometer to nanometer diameter active areas

Abstract

This article proposes a method of fabricating a hyperboloid-drum structure, which can be applied to develop an electrically pumped laser with an active-layer diameter as small as 100 nm, while maintaining a wide contact area for easy electrical connection. The structure is fabricated using conventional photolithography and the chemically assisted ion-beam etching (CAIBE) process with an Ar:Cl2:BCl3=5:2:3 gas mixture. The process conditions for CAIBE and the size of etch mask are adjusted to obtain the required structure with a height of ∼8 μm, an active layer diameter of 0.1–2.0 μm, and a contact diameter larger than 4 μm. It is demonstrated that a laser device with an active layer diameter as small as 600 nm and a contact layer diameter of ∼5 μm can also be fabricated with the proposed method.