PHT.301 Physics of Semiconductor Devices

x-ray image of a diode

Discrete diodes often have two wire leads that can be inserted into holes in a printed circuit board. This is called Through-Hole Technology (THT). Below to the left is an image of a power diode and on the right is an x-ray image of what is inside. The extent of the black plastic packaging is shown by the dashed white lines.

C: metal wire leads that extend out side the black plastic packaging. D: Thicker metal parts to make contact to the semiconductor. S: The semiconducting die.