Thermoreflectance Imaging of Semiconductor Lasers With a Numerical Thermal Model

High resolution surface temperature maps of a slotted surface grating laser operating at approx. 1550 nm are obtained by means of CCD-thermoreflectance imaging. The resolution is such that the temperature of the 2 µm wide ridge can be determined. Experimental temperature profiles along the ridge and in the lateral direction are provided. A 2D numerical model is developed to simulate the steady state thermal distributions in the laser. There is good agreement between the experiment and simulation. This technique allows for high-resolution imaging and will be useful where hot spots occur on laser devices.