Abstract: This paper analyzed the load on a single compact in a PDC bit while drilling, and studied the improvement measures for the phenomenon such as separated out from the diamond layer and the carbide substrate. The shear force on the diamond layer in the compact is the main factor, which is related to shear cutting action on the carbide substrate and causes the diamond separated out from the carbide substrate. The results show that the shear stress can be increased by increasing the contact area between the diamond layer and the carbide substrate. Therefore, this paper still studied a suitable substrate structure and shape, through the development of the surface on the substrate by different groove shapes to increase the contact area between the two, so that it can be enough to get the connection strength. Lastly, some experimental analysis were enumerated for some PDC bits with checkerboard-like groove substrates.