本文選題：二氧化鋯　切入點(diǎn)：二氧化鉿　出處：《大連理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：以HfO：和ZrO2為基的二元氧化物材料因具有高介電常數(shù)(High-k),在微電子領(lǐng)域早已成為研究熱點(diǎn)并被實(shí)際大規(guī)模應(yīng)用,已廣泛取代SiO2作為金屬氧化物半導(dǎo)體(CMOS)晶體管柵介質(zhì)和動(dòng)態(tài)隨機(jī)存儲(chǔ)器(DRAM)電容器介質(zhì)。近幾年的研究發(fā)現(xiàn),使用特殊工藝制備的HfO2基薄膜具有優(yōu)異的鐵電性質(zhì)。若采用該類鐵電材料取代Pb(Zr,Ti)O3 (PZT)、SrBi2Ta2O9(SBT)和(Bi1-xLax)4Ti3O12 (BLT)等傳統(tǒng)的鈣鈦礦結(jié)構(gòu)基鐵電材料來制備鐵電半導(dǎo)體器件如鐵電非易失性存儲(chǔ)器,預(yù)計(jì)在存儲(chǔ)密度和性能方面或?qū)⒂兄卮笸黄啤１菊撐囊约{米薄膜材料的相變理論為指導(dǎo),采用對(duì)設(shè)備條件要求不高、操作簡單的純水基溶膠-凝膠法制備HfxZr1-xO2(x=0、0.5、1)薄膜。實(shí)驗(yàn)中,對(duì)純水基溶膠-凝膠法制備工藝進(jìn)行了探索和優(yōu)化,利用熱重/差熱同步分析儀分析溶膠的熱性能；利用甩膠法制備薄膜；利用原子力顯微鏡(AFM)以及掃描電鏡(SEM)測(cè)定薄膜的表面形貌：利用X射線反射(XRR)法對(duì)薄膜厚度、密度及表面粗糙度進(jìn)行分析；利用掠入射X射線衍射(GIXRD)法對(duì)薄膜物相進(jìn)行分析；利用X射線光電子能譜(xPS)分析薄膜各元素含量和化學(xué)鍵結(jié)合情況；利用鐵電性能測(cè)試分析儀對(duì)薄膜電容器的極化曲線、漏電流密度等電性能進(jìn)行測(cè)試。實(shí)驗(yàn)結(jié)果表明,純水基溶膠-凝膠法可實(shí)現(xiàn)對(duì)薄膜厚度的精確控制。表面AFM形貌圖顯示薄膜表面光滑、平整且無明顯的氣孔和微裂紋。XPS結(jié)果顯示薄膜各元素含量比符合化學(xué)計(jì)量比。GIXRD結(jié)果顯示60.0nm的Zr02薄膜在550℃-600℃發(fā)生晶化,室溫下呈四方相,60.0nm厚的Hf02薄膜在600℃-700℃發(fā)生晶化,室溫下呈單斜相。由于表面能效應(yīng),薄膜厚度與相組成密切相關(guān),隨著薄膜厚度的增加,Hf0.5Zr0.5O2薄膜在室溫下的結(jié)晶相由四方相逐漸向單斜相轉(zhuǎn)變。ZrO2的添加有助于Hf02四方相的穩(wěn)定,在12.9nm以下,Hf0.5Zr0.5O2薄膜在室溫下完全結(jié)晶為四方相。相組成與薄膜介電常數(shù)密切相關(guān),反映到P-E測(cè)量曲線中,14.7nm HfO2、12.9nm Hf0.5Zr0.5O2和29.5nm ZrO2薄膜室溫下的結(jié)晶相為單斜相向四方相轉(zhuǎn)變,對(duì)應(yīng)于介電常數(shù)依次增大,分別為13.6、27.8和42.1,薄膜漏電流密度在場(chǎng)強(qiáng)為1MV/cm下分別為2.4×10-6、3.5×10-6和2.2×10-6A/cm2。
[Abstract]:Due to their high dielectric constant, the binary oxide materials based on HFO: and ZrO2 have become a hot spot in the field of microelectronics and have been widely used in many fields. SiO2 has been widely replaced as gate dielectric of metal oxide semiconductor (MOSFET) transistor and capacitor dielectric of dynamic random access memory (DRAM). HfO2 based thin films prepared by special process have excellent ferroelectric properties. Traditional perovskite-based ferroelectric materials such as PbBZZrTiO3 / PZTO _ 3, SrBi2Ta2O9SBTand Bi1-xLaxTi3O12) are used to fabricate ferroelectric semiconductor devices such as ferroelectric nonvolatile memory. It is expected that there will be a great breakthrough in storage density and performance. HfxZr1-xO2O2HfxZr1-xO2OXO00.51) thin films are prepared by pure water-based sol-gel method, which is guided by phase transition theory of nanocrystalline thin films. The preparation process of pure water based sol-gel method was explored and optimized. The thermal properties of sols were analyzed by thermogravimetric / differential thermal synchronous analyzer (TG-DTA), and the films were prepared by gelation method. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to determine the surface morphology of the films. The thickness, density and surface roughness of the films were analyzed by X-ray reflectance (XRR) method, and the phase of the films was analyzed by grazing incident X-ray diffraction (GIXRD) method. X-ray photoelectron spectroscopy (XPS) was used to analyze the element content and chemical bond binding of the film, and the polarization curve, leakage current density and other electrical properties of the thin film capacitor were measured by ferroelectric property analyzer. The pure water based sol-gel method can accurately control the film thickness. The surface AFM topography shows that the film surface is smooth. The results of flat and no obvious porosity and microcrack. XPS showed that the content ratio of each element in the film was in accordance with stoichiometric ratio. The results showed that 60.0nm Zr02 film crystallized at 550 鈩，

本文編號(hào)：1614732