Arsenic-Doped n-Type Diamond Grown by Microwave-Assisted Plasma Chemical Vapor Deposition

We grew n-type arsenic (As)-doped single-crystal diamond layers using tertiarybutylarsine as an As source. The n-type conduction of the As-doped layers was confirmed both in Hall measurements and from the current?voltage characteristics of the diodes. In the As-doped layers, electron concentration increased with As concentration in the layers. The ionization energy of the As donor decreased from 1.6 to 0.7 eV with As concentration from 1?1017 to 9?1019 cm-3. A diamond p?n junction diode with an n-type As-doped layer exhibited a rectification ratio of ?1000 at ?10 V at room temperature.