为改进以醇盐为原料溶胶-凝胶制备LaNiO3(LNO)薄膜工艺中存在的诸多苛刻因素,本文以无机盐为原料,利用湿化学工艺在硅衬底上制备了LNO薄膜,La(NO3)3·6H2O和Ni(NO3)2·6H2O冰醋酸溶液通过配体交换形成金属醋酸盐的冰醋酸溶液,回流时用乙酸酐(CH3CO)2O除硝酸根和结晶水,而乙酰丙酮(AcAc)部分取代醋酸盐分子中的醋酸根而形成的M(OAc)n-x(AcAc)x(M=La3+或Ni2+)能部分水解形成M(OH)n-x(AcAc)x.该羟基金属离子通过羟基聚合并与甲基纤维素(MCL)形成线状结构LNO溶胶,易于成膜.LNO薄膜经过550-850℃/60min退火形成多晶膺立方钙钛矿结构,其晶格参数a=3.84(A).四引线法测定厚度0.6μmLNO薄膜电阻率与温度的变化在-163-150℃之间能符合ρ=ρ0+AT2关系式.在1KHz测试频率下,测得Pb(Zr0.52Ti0.48)O3(PZT)(52/48)薄膜剩余极化强度Pr在LNO/Pt/Ti/SiO2/Si衬底和Pt/Ti/SiO2/Si衬底上分别为19.6和23.5μC·cm-2,矫顽场分别为76.1和85.1 kV·cm-1.%Basing on improving harsh conditions of sol-gel process of alkoxides, a dense conductive LaNiO3 (LNO)films on SiO2/Si substrates were fabricated by sol-chemical process with corresponding inorganic salts. Lanthanum acetate and nickel acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate and nickel nitrate tetrahydrate after being refluxed, (CH3CO)2O removed nitrates and the crystallized H2O completely. Acetylacetone (AcAc) was partially bidentated with the metallic ion of the metallic acetates and formed M(OAc)n-x (AcAc)x, which were hydrolyzed into M( OH)n-x ( AcAc)xby adding 10ml 0. 4％ MCL ( methyl cellulose) solution. The M (OH)n-x (AcAc)x/2, polymerizing and combining with MCL, formed LNO sol precursor with heteropolymeric structure and filming easily. Perovskite LNO films were annealed at 550-850℃/60min and its lattice parameter is 0. 384 nm. The temperature dependence of resistivity for LNO film with 0. 6μm thickness that measured by the four-probe method can fit well by the ρ = ρ0 + AT2 between -163-150℃. The remnant polarizations and coereive rields for Ph( Zr0.52Ti0.48 )O3 (PZT)(52/48) thin films with LNO/Pt/Ti/SiO2/Si and Pt/Ti/SiO2/Si as substrates are 19. 6 and 23.5μC · cm-2 , 76. 1 and 85.1 kV ·cm-1 respectively at 1 KHz.
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