ZnO film is of great interest for short-wavelength optoelectronic application because ZnO semiconductor with a wide band gap of 3.34 eV has a large exciton binding energy of 60 meV at room temperature.However

there is almost no application based on the active function as a compound semiconductor.The primary reason is because most active functions in semiconductors come from the characteristic properties of p-n junction but the preparation of p-ZnO is in difficulty.There is of interest in the p-n heterojunction diode fabricated by using a combination of p-type oxide conductor and n-type ZnO.In this paper Cu

2

O was chosen to compose p-n heterojunction with n-type ZnO.Cu

2

O as a p-type direct-gap semiconductor with a bandgap energy of 2.1 eV

has been regarded as one of the most promising materials used for optoelectronic applications recently.Cu

2

O is a potential photovoltaic material due to the low cost

non-toxicity and the natural abundance of the base material.Furthermore

Cu

2

O is one of the few oxide semiconductors that are p-type.The nature of the p-type conductivity of Cu

2

O is originated from the presence of Cu vacancies which form an acceptor level above the valence band.The heterojunction was prepared by two step cathodic electrodeposition.Electrodeposition is a simple and convenient method.It has several advantages also

such as low processing temperature

higher deposition rates

controllable film thickness and morphology.Uniform films can be formed on various substrates with complex shapes and employed with inexpensive equipments.The kinetics of electrodepostion of Cu

2

O was discussed.X-ray diffraction

scanning electron microscopy

UV-Vis transmittance technologies were used to investigate the structural properties of the heterojunction.The electrical properties were also studied by measuring the I-V characteristic.The results showed that this simple electrochemical route was a favorable method to fabricate Cu

2

O/ZnO heterojunciton.