Relationship between applied voltage to cause discharge and movement of carriers for rhodium-plated contact reed switches

Reed switches have been used in various fields of application due to excellent reliability and compactness. The progress of electronics is leading to increasing demand for enhanced functions of the reed switch. One such demand is high breakdown voltage between contacts. To achieve the improvement in breakdown voltage, fundamental research on discharge phenomena is very important. We studied the relationship between applied voltage to cause discharge and movement of carriers for rhodium-plated contact reed switches. Using Auger electron spectroscopy (AES), we analyzed contact surfaces before and after discharge caused by various applied voltages. Amount of nitrogen and amount of oxygen were found to increase on the cathode surface and on the anode surface, respectively, after discharge. Furthermore, we found that this increase was accelerated by enhancing applied voltage to cause discharge. On the contrary, amount of oxygen was found to decrease on the cathode surface after discharge. We found that this decrease was also accelerated by enhancing applied voltage to cause discharge. These results revealed that the nitrogen cation and oxygen anion moved as carriers through discharge and that this movement was accelerated by increasing applied voltage to cause discharge.