A new quantum cascade laser is reported with very high performance at high temperatures. These high performances are obtained by a design combining low doping, a funnel injector and a three well vertical transition active region. A molecular beam epitaxy grown InP top cladding layer is also used to optimize heat transport. Peak pulsed optical power of 200 mW and average power of 6 mW are obtained at 300 K and at a wavelength lambda = 5.2 mu m. The devices operate also in continuous wave up to 140 K with 2 mW of optical power.