Broad area, high power CW operated InGaN laser diodes

We demonstrate the operation of wide-stripe InGaN laser diodes grown on bulk gallium nitride substrates obtained by high-pressure synthesis. The use of almost dislocation-free substrates resulted in very low defect densities of obtained laser structures - typically in the range of 10(5) cm(-2). We tested 3 types of devices of the dimensions: 20 mu mx500 mu m, 20 mu mx1000 mu m and 50 mu mx500 mu m. All three types of lasers showed good properties during pulse current experiments, exhibiting threshold currents of 400, 850 and 950 mA, respectively. The lasing wavelength varied between 405 and 420 nm, depending on the particular device. After p-down mounting on diamond heatspreaders, the first two types of lasers showed CW operation with a total output power reaching 200 mW. These devices, after optimization, offer good prognostics for reaching an optical power in the I W range needed for the applications in large area displays.