Over the last few years thin disks lasers have shown breakthrough records in both average power and peak power [1,2]. The optimization of the bonding process for mounting the laser disk to the base heat sink is key to achieving these impressive levels of performance. Processes using UV-adhesive bonding on diamond [1] or soldering [3] have regularly been reported. Direct-bonding is a promising solution to further improve the thermal contact between the disk and the substrate [3,4], but to the best of our knowledge this process has not been applied to thin disk lasers for high power, single mode operation. In this work, we characterize an Yb:YAG thin disk bonded on silicon carbide (SiC) using an adhesive-free, direct-bonding process developed by Crystalline Mirror Solutions (CMS). We employ this thin disk in a laser cavity to obtain 178 W of CW output power in a single TEM00 mode beam.