Fabrication And Study Of Cu₂O/ZnO Junction For Application In Betavoltaics And Photovoltaics

Isotopic batteries and solar cells are two kinds of clean energy batteries which have been widely concerned and studied recently.The isotopic battery is a device that converts the decay energy of isotopes into electric energy.Because of its low output power and strong anti-interference,it mainly supplies electric energy for micro-electro-mechanical system（MEMS）in the extreme environment.However,mostβisotopic batteries use homojunction as the energy conversion unit,which have the problems of complex structure and manufacturing processes.Compared with isotopic decay energy,solar energy is a kind of energy obtained easily and distributed widely in the daily life,thus it has a faster development and fruitful results.As a new research direction of solar cell,the semi-transparent solar cell has a wide prospect.This paper studies the Cu₂O/Zn O heterojunction with simple fabrication process and structure as the energy conversion units of theβisotopic battery and the semi-transparent solar cell.This paper introduces the research history and current situation of the isotopic battery and the solar cell,as well as the characteristics of semiconductor material and working principle of p-n heterojunction,finally verifies the possibility of Cu₂O/Zn O heterojunction working as the energy conversion units in theβisotopic battery and the semi-transparent solar cell.The main research contents and achievements are as follows:By using direct current magnetron sputtering technique,Zn O thin films with high transmittance in visible and near infrared spectral are fabricated.In the spectral region of400～1100nm,the highest average transmittance reaches 82%.By controlling of Ar/O₂ gas flow ratio,the（002）preferred orientation Zn O thin films with good crystallinity are obtained.By using direct current magnetron sputtering technique,the（110）,（111）and（200）preferred orientation Cu₂O are fabricated.By controlling of Ar/O₂ gas flow ratio,Cu₂O thin films with the average transmittance varying from 31%～49%in the spectral region of500～1100 nm are obtained.The thickness of Cu₂O thin film is measured by scanning electron microscope.The deposition rate of Cu₂O thin film is much higher than that of Zn O thin film,by calculating the deposition rate of them.Fabrication factors of Cu₂O/Zn O heterojunction are determined by analyzing the properties of Zn O and Cu₂O.The thickness of heterojunction is accurately measured by energy dispersive analysis of X-rays together with scanning electron microscope.The Cu₂O/Zn O heterojunctions with diode characteristic are obtained by changing the thickness of layers,which have certain conversion ability of converting decay energy and light energy into electric energy respectively,under the irradiation of ⁹⁰Srβradioactive source with activity of 10.27m Ci and the irradiation of AM1.5 standard simulated sunlight source.The results show that this project provide a certain basis on the application of Cu₂O/Zn O heterojunction in the isotopic battery and the semi-transparent solar cell.