Molecular beam epitaxial growth of copper phthalocyanine on Si (111)

Copper phthalocyanine (CuPc) thin films were deposited by molecular beam epitaxy on n-Si (111) substrates whose surface dangling bonds were terminated with hydrogen. The deposited films are found to be contaminated with oxygen and show p-type conductivity. The fabricated CuPc/Si p-n heterojunction diode exhibits rectification in the I-V characteristic with relatively large reverse leakage current, which is associated with trap-assisted tunneling via traps at the CuPc/Si interface resulting from incomplete hydrogen-termination of Si dangling bonds. It is also interesting to find strong blue-green light emission from the CuPc film exposed to the UV light