Resistive Switching Of Mn-doped ZnO Based On PET Flexible Substrate

With the growth of society and technology, people have more and more electronic products, such as cameras, smart phones, tablets and so on, which totally change our life. In an era with explosive information, it is more and more necessary for us to deal with it and our demand for storing information becomes larger and larger. Although Flash technology still plays an important role in non-volatile memory, its technological bottlenecks greatly limit the development of nonvolatile memories. Hence finding a new generation of nonvolatile memories becomes a hot topic in many famous semiconductor companies and research institutions. Some nonvolatile memories like magnetic random access memory(MRAM), ferroelectric random access memory(FRAM) and phase change random access memory(PRAM) have been reported currently. However, resistive switching random access memory(RRAM)is no doubt a promising candidate for replacing the Flash memory considering its overwhelming advantage.RRAM based on binary transition metal oxides, due to its high compatibility of CMOS, remarkable Noise Tolerance and so on, is regarded as the strongest competitor of memory replacing the Flash technology. Therefore, studying materials with resistive switching characters to prepare high-performance RRAM has its great significance. As a wide-bandgap semiconductor material, ZnO has been most widely studied. ZnO is one of the most important binary transition metal oxides with wurtzite structure, 3.37 eV bandgap and 60 mV exciton binding energy at room temperature. Hence ZnO has great application prospects in fields of laser diodes, short-wavelength light-emitting diodes and low threshold current devices. In addition, its high mobility and transparency meets the need of application in micro-electronics. Therefore, ZnO was chosen as resistive-switching material in this thesis.In this thesis, ZnO were deposited on PET flexible substrate by pulsed laser deposition. The resistance switching(RS) behavior of ZnO grown with different O2 pressure, laser energy and thickness has been studied. Afterwards Mn-doped ZnO thin films were prepared and tested on electrical performance after top electrodes have grown. The study shows:1. ZnO thin films grown on 10 Pa O2 pressure, 140 mJ laser energy and 100 nm thickness have better structure and RS performance than other parameters;2. ZnO thin film’s best growth parameters can well transplant into Mn-doped Zn O. The electrical-performance test show that doping Mn can well increase ZnO initial resistance and greatly enhance ZnO thin films’ RS window.3. The I-V relationships of ZnO thin films have been studied and their I-V curves fit well in theoretical curve of Schottky emission mechanism, indicating that charge modification of the Schottky barrier interface effect theory can well explain the conductive mechanism of ZnO thin films.