We present 6.1 W of output power from a flip-chip semiconductor disk laser (SDL) emitting in the 1.3 mu m wavelength region. This is the first demonstration of a flip-chip SDL in this wavelength range with output powers that are comparable to those obtained with intracavity diamond heat spreaders. The flip-chip configuration circumvents the optical distortions and losses that the intracavity diamond heat spreaders can introduce into the laser cavity. This is essential for several key applications of SDLs. (C) 2014 Optical Society of America