We have demonstrated high density, 2D (4x12) VCSEL arrays operating at an aggregate data rate of over 480Gb/s in an aerial density of 1400x3750 μm2, or 9.14 Tbs/cm2. These flip-chip, bottom-emitting 990nm VCSELs have low drive voltage, low electrical parasitics, improved thermal impedance and 2D scalability over their wire-bonded top emitting counterparts. Excellent high speed performance was obtained through the use of 1) compressively strained InGaAs MQW active region 2) low parasitic capacitance oxide-confined VCSEL structures and 3) low series resistance, high index contrast AlGaAs/GaAs mirrors. 10Gb/s operation was obtained with low operating current density of ~6kA/cm2 at 70C. Our best results to date have achieved data rates greater than 12.5Gb/s @70C at a current density less than 10kA/cm2. The device results show good agreement with theoretically calculated/simulated values.
This work was partially supported by DARPA under contract MDA972-03-3-0004.