A method of manufacturing a substrate with reduced threading dislocation density is disclosed, which comprises: (i) at a first temperature, forming a first layer of wafer material on a semiconductor substrate, the first layer arranged to be doped with a first concentration of at least one dopant that is different to the wafer material; and (ii) at a second temperature higher than the first temperature, forming a second layer of the wafer material on the first layer to obtain the substrate, the second layer arranged to be doped with a progressively decreasing concentration of the dopant during formation, the doping configured to be decreased from the first concentration to a second concentration. The wafer material and dopant are different to silicon. A related substrate is also disclosed.