A semiconductor device sub-assembly comprising: a plurality of semiconductor units laterally spaced to one another; a semiconductor unit locator comprising a plurality of through-holes, wherein each semiconductor unit is located in a respective through-hole of the semiconductor unit locator; a plurality of pressure means for applying pressure to each semiconductor unit, wherein the pressure means comprises a spring; a conductive malleable layer located at the lower surface of the semiconductor unit locator between the plurality of pressure means and the plurality of semiconductor units located in the semiconductor unit locator; a spring locator comprising a plurality of through-holes, wherein each pressure means is located in a through-hole of the spring locator; and a first thrust pad and a second thrust pad within the through-holes of the spring locator on either side of the pressure means, wherein each second thrust pad is in contact with the conductive malleable layer, wherein the pressure means is selected such that a predetermined pressure is applied on each semiconductor unit at a threshold pressure limit when clamping the semiconductor device sub-assembly to apply a clamping pressure which compresses each pressure means to a degree that a lower most surface of the first thrust pad is in line with a lower most surface of the spring locator, and wherein, when a clamping pressure lower than the threshold pressure limit is applied, each first thrust pad is protruded from the lower most surface of the spring locator, and wherein when a clamping pressure above the threshold pressure limit is applied it is supported by the spring locator and the semiconductor unit locator a plurality of semiconductor units laterally spaced to one another; a semiconductor unit locator comprising a plurality of through-holes, wherein each semiconductor unit is located in a respective through-hole of the semiconductor unit locator; a plurality of pressure means for applying pressure to each semiconductor unit, wherein the pressure means comprises a spring; a conductive malleable layer located at the lower surface of the semiconductor unit locator between the plurality of pressure means and the plurality of semiconductor units located in the semiconductor unit locator; a spring locator comprising a plurality of through-holes, wherein each pressure means is located in a through-hole of the spring locator; and a first thrust pad and a second thrust pad within the through-holes of the spring locator on either side of the pressure means, wherein each second thrust pad is in contact with the conductive malleable layer, wherein the pressure means is selected such that a predetermined pressure is applied on each semiconductor unit at a threshold pressure limit when clamping the semiconductor device sub-assembly to apply a clamping pressure which compresses each pressure means to a degree that a lower most surface of the first thrust pad is in line with a lower most surface of the spring locator, and wherein, when a clamping pressure lower than the threshold pressure limit is applied, each first thrust pad is protruded from the lower most surface of the spring locator, and wherein when a clamping pressure above the threshold pressure limit is applied it is supported by the spring locator and the semiconductor unit locator