Development of p-type amorphous Cu1−xBxO2−δ thin films and fabrication of pn hetero junction

• Growth of p-type semiconducting amorphous Cu1−xBxO2−δ thin films by co-sputtering.
• Atomic percentage of Cu1−xBxO2−δ thin films from the XPS analysis.
• Variation of bandgap with boron concentration in Cu1−xBxO2−δ thin films.
• Demonstration of p–n hetero junctions fabricated in the structure n-Si/p-Cu1−xBxO2−δ/Au.

Transparent conducting amorphous p type Cu1−xBxO2−δ thin films were grown by RF magnetron co-sputtering at room temperature, using copper and boron targets in oxygen atmosphere. The structural, electrical as well as optical properties were studied. Composition of the films was analyzed by XPS. Amorphous structure of as deposited films was confirmed by GXRD. Surface morphology of the films was analyzed by AFM studies. p-Type nature and concentration of carriers were investigated by Hall effect measurement. Band gap of the films was found to increase with the atomic content of boron in the film. A p–n hetero junction using p-type Cu1−xBxO2−δ and n-type silicon was fabricated in the structure n-Si/p-Cu1−xBxO2−δ/Au which showed rectifying behavior. As deposited amorphous Cu1−xBxO2−δ thin films with lower carrier concentration can be used as a channel layer for thin film transistors.