Abstract: A semiconductor device includes an array of VCSEL devices with an annealed oxygen implant region (annealed at a temperature greater than 800° C.) that surrounds and extends laterally between the VCSEL devices. A common anode and a common cathode can be electrically coupled to the VCSEL devices, with the common anode overlying the annealed oxygen implant region. The annealed oxygen implant region can funnel current into active optical regions of the VCSEL devices and provide current isolation between the VCSEL devices while avoiding an isolation etch between VCSEL devices. In another embodiment, a semiconductor device includes an annealed oxygen implant region surrounding a VCSEL device. The VCSEL device(s) can be formed from a multi-junction layer structure where built-in hole charge Qp for an intermediate p-type layer relative to built-in electron charge Qn for a bottom n-type layer is configured for diode-like current-voltage characteristics of the VCSEL device(s).