A multi-layer laser diode mount is configured with a submount made from thermo- and electro-conductive material. One of the opposite surfaces of the submount supports a laser diode. The other surface of the submount faces and is spaced from a heatsink. The submount and heatsink are configured with respective thermal expansion coefficients (“TEC”) which are different from one another. The opposite surfaces of the submount are electroplated with respective metal layers one of which is bonded to a soft solder layer.In one aspect of the disclosure, the mount is further configured with a spacer having the same TEC as that of the submount and bonded to the soft solder layer. A layer of hard solder bonds the spacer and heatsink to one another.In a further aspect of the disclosure, the electroplated metal layer in contact with the other surface of the submount is hundred- or more micron thick. The soft solder is directly bonded to the heatsink.In both aspects of the disclosure, a temperature of a p-n junction of the laser diode remains substantially constant within a 0 to 2° C. temperature range through a predetermined amount of several hundred of repeated thermo-cycles which is indicative of uncompromised integrity of the soft solder.