Indium tin oxide transparent electrodes for broad-area top-emitting vertical-cavity lasers fabricated using a single lithography step

We report for the first time top emitting buried oxide vertical cavity lasers using transparent indium tin oxide electrodes, Our process enables broad-area VCSEL's to be fabricated in a single lithography step, thus allowing the fast turn-around time necessary for evaluating VCSEL epitaxial materials. The ITO contacts attain a peak transmission of 96%, a specific contact resistance of 10(-5) Omega . cm(2), and a sheet resistivity of 2.5x10(-4) Omega . cm. Under room temperature CW pumping, the devices exhibit a minimum threshold current density of 1.2 kA/cm(2) at a wavelength of 801 nm, and have a maximum light output power of 5.2 mW.