01 Rectifier diode
Yesterday I saw the internal structure of a rectifier diode shown by others on the Internet, and I happened to have a few relatively large rectifier diodes on hand. Use diagonal pliers to remove the non-black epoxy resin on the outside and observe its internal structure. Two copper electrodes can be clearly seen, soldered to both ends of the internal semiconductor sheet. The exposed semiconductor appears to be a single piece. The structure of the internal P and N semiconductor fusion cannot yet be seen.
Using a multimeter, measure across the diode with the case open. You can see that its forward conduction voltage is about 0.35V, so this is a Schottky diode. That is, the PN junction formed by metal and P-type semiconductor. So the crystal inside the diode has only one P-type semiconductor. Measuring the resistance of the diode in reverse direction, you can see that it is about 300k ohms. This also reflects that the reverse leakage of Schottky diodes is larger than that of ordinary silicon diodes. In addition, it is also seen that the diode is not very sensitive to external light. Schottky diodes are relatively simple internally.
※ Summary ※
This article looks at a Schottky diode with its case open. See that there is only one semiconductor crystal inside. The forward conduction voltage of this diode is about 0.35V. Not sensitive to external light. Maybe it's because the infrared component of external light is relatively small.
