Abstract
In this thesis, we use the atomic-layer-deposition (ALD) technique to prepare high-κ dielectrics, including HfO2 and HfO2 incorporated with Al into different structures, on H-terminated silicon substrate、hydrous-plasma-treated Pt and TiN bottom electrodes for MOSFET gate oxide and DRAM capacitor application.In the beginning, we start our study with the deposition of HfO2 thin film by ALD using Hf[N(C2H5)(CH3)]4 and H2O vapor as precursors on the H-terminated silicon substrate and investigate the material and electrical properties of HfO2 thin film as gate oxide in detail. Satisfactory results are discussed and illustrated in the Chapter 2. In addition, we study the effect of the incorporation of Al atom into HfO2 thin film in the form of HfAlOx alloy and HfO2/Al2O3 stack structures for comparison in the Chapter 3. The results show that the HfAlOx alloy exhibits the best performance against the thermal degradation due to its amorphous structure compared with pure HfO2 and HfO2/Al2O3 stack. Besides, in Chapter 4, the DRAM capacitors are prepared with HfO2、HfAlOx alloy and (HfO2/Al2O3)*3 nanolaminate as insulators by ALD on the hydrous-plasma-treated Pt and TiN electrodes. The results show that the (HfO2/Al2O3)*3 nanolaminate exhibit lowest leakage current performance in these oxides and higher capacitance density than HfAlOx alloy. It indicates that the (HfO2/Al2O3)*3 nanolaminate is more suitable for DRAM application. In Chapter 5, the deposition of TiO2 thin film by ALD using Ti[N(CH3)2]4 and H2O vapor as precursors on the H-terminated silicon substrate are also demonstrated. In addition, the performance of incorporation of Al into TiO2 forming TiAlOx alloy and Al2O3/TiAlOx/Al2O3 sandwich structure as gate oxide are also investigated. The result show that the TiAlOx alloy and Al2O3/TiAlOx/Al2O3 sandwich exhibit pretty low EOT value (less than 1nm) which are suitable for 45~32nm technology MOSFET application.