低压力Cu布线CMP速率的研究

采用低介电常数材料(低k介质)作为Cu布线中的介质层,已经成为集成电路技术发展的必然趋势.由于低k介质的低耐压性,加工的机械强度必须降低,这对传统化学机械抛光(CMP)工艺提出了挑战.通过对CMP过程的机理分析,提出了影响低机械强度下Cu布线CMP速率的主要因素,详细分析了CMP过程中磨料体积分数、氧化剂体积分数、FA/O螯合剂体积分数等参数对去除速率的影响.在4.33 kPa的低压下通过实验得出,在磨料体积分数为20%,氧化剂体积分数为3%,FA/O螯合剂体积分数为1.5%时可以获得最佳的去除速率及良好的速率一致性.     

直流磁控溅射制备非晶硅薄膜的研究

非晶硅薄膜(a-Si)是目前重要的光敏材料,在很多领域得到广泛应用.直流磁控溅射具有工艺简单,沉积温度低等优点,是制备薄膜的一种重要技术.采用直流磁控溅射工艺在玻璃基板上沉积薄膜,并对样品进行了退火处理.研究了沉积速率与溅射功率的关系.结果表明薄膜的沉积速率与溅射功率近似有线性关系.利用X射线衍射(XRD)对薄膜进行了分析鉴定,结果表明溅射的薄膜是非晶硅薄膜.利用扫描电子显微镜(SEM)对非晶硅薄膜的表面形貌进行了观察和分析,与X射线衍射测试的结果一致.所以,利用直流磁控溅射工艺能在常温下能快速制备出良好的非晶硅薄膜.     

CMP中酸碱度对InSb晶片粗糙度的影响

InSb是一种重要的半导体材料。研究了在压力、流量等工艺参数一定的条件下,通过改变有机碱在抛光液中的体积分数,得到了不同pH值的抛光液。采用化学机械抛光(CMP)对InSb进行了表面加工,并在原子力显微镜下观测了抛光后晶片的表面粗糙度,找到了适宜InSb抛光的最佳pH值,从而达到降低InSb表面粗糙度的目的,最后分析和讨论了实验结果及其有机碱在CMP中的作用,最终实现了工艺参数的优化。     

多晶Si太阳电池表面酸腐蚀制绒的研究

研究了采用HF和HNO3非择优腐蚀多晶硅表面制备绒面的机理。通过实验分析了酸混合液的体积浓度配比、添加剂、温度和时间等因素对腐蚀速率和腐蚀后表面形貌的影响;总结出了多晶Si的酸腐蚀规律,得到了制备理想绒面的酸混合液体积配比(V(HF):V(HNO3):V(CH3COOH)=1∶12∶6)。在此基础上提出了优化设计方案:采用廉价的水代替醋酸作为缓蚀剂,腐蚀过程置于超声槽中进行,利用超声波的振动使反应生成的气泡快速脱离多晶Si片表面,同时使腐蚀液浓度分布更加均匀,从而制备出效果更佳的多晶Si绒面。     

超滤和活性剂协同作用对铜阻挡层CMP后缺陷的控制机理研究

在铜互连阻挡层化学机械抛光(CMP)过程中,由于工艺和材料等因素会产生划伤和沾污等缺陷问题,造成器件失效、良率降低及潜在可靠性等问题.研究了抛光液中活性剂及超滤工艺对CMP后缺陷的影响,提出了活性剂和超滤协同控制CMP后缺陷的作用机理.通过粒径和大颗粒测试仪表征抛光液粒径和大颗粒数的变化,通过扫描电子显微镜(SEM)和...     

机电控制技术应用相关前沿技术研究

现阶段的机电控制技术被广泛运用在各个领域,但作为应用类技术,该技术仍然存在一定的缺陷。机电控制技术在相关技术不断成熟的的基础上,机电设备性能得到了较大的提升。本文从机电控制技术各项技术入手,分别分析和探讨了信息处理技术、自动控制技术和远程控制技术,以提高机电控制技术的社会利用率。     

多层铜布线CMP后表面残留CuO颗粒的去除研究

This article introduces the removal technology of CuO particles on the post CMP wafer surface of multi-layered copper. According to the Cu film corrosion curve with different concentrations of HEO2 and the effect curve of time on the growth rate of CuO film, CuO film with the thickness of 220 nm grown on Cu a surface was successfully prepared without the interference of CuC12.2H20. Using the static corrosion experiment the type of chelating agent （FA/O II type chelating agent） and the concentration range （10-100 ppm） for CuO removal was determined, and the Cu removal rate was close to zero. The effect of surfactant on the cleaning solution properties was studied, and results indicated that the surfactant has the effect of reducing the surface tension and viscosity of the cleaning solution, and making the cleaning agent more stable. The influence of different concentrations of FA/O I type surfactant and the mixing of FA/O II type chelating agent and FA/O I type surfactant on the CuO removal effect and the film surface state was analyzed. The experimental results indicated that when the concentration of FA/O I type surfactant was 50 ppm, CuO particles were quickly removed, and the surface state was obviously improved. The best removal effect of CuO on the copper wiring film surface was achieved with the cleaning agent ratio of FA/O II type chelating agent 75 ppm and FA/O I type surfactant 50 ppm. Finally, the organic residue on the copper pattern film after cleaning with that cleaning agent was detected, and the results showed that the cleaning used agent did not generate organic residues on the film surface, and effectively removes the organic residue on the water.     

Electrochemical investigation of copper chemical mechanical planarization in alkaline slurry without an inhibitor

This work investigates the static corrosion and removal rates of copper as functions of H202 and FA/OIIconcentration, and uses DC electrochemical measurements such as open circuit potential （OCP）, Tafel ana- lysis, as well as cyclic voltammetry （CV） to study HaOa and FA/OIIdependent surface reactions of Cu coupon electrode in alkaline slurry without an inhibitor. An atomic force microscopy （AFM） technique is also used to measure the surface roughness and surface morphology of copper in static corrosion and polishing conditions. It is shown that 0.5 vol.% H202 should be the primary choice to achieve high material removal rate. The electro- chemical results reveal that the addition of FA/O II can dissolve partial oxide film to accelerate the electrochemical anodic reactions and make the oxide layer porous, so that the structurally weak oxide film can be easily removed by mechanical abrasion. The variation of surface roughness and morphology of copper under static conditions is consistent with and provides further support for the reaction mechanisms proposed in the context of DC electro- chemical measurements. In addition, in the presence of H202, 3 vol.% FA/O II may be significantly effective from a surface roughness perspective to obtain a relatively flat copper surface in chemical mechanical planarization （CMP） process.     

GLSI多层铜布线CMP后BTA去除研究

本文通过静态腐蚀速率的方法分析确立了碱性清洗剂中FA/OⅡ型螯合剂和FA/OⅠ型表面活性剂对BTA的去除规律。通过单因素实验和复合清洗剂的实验优化,确定了去除BTA的清洗剂配方,并通过接触角实验进一步证实实验结果的有效性。最后,将优化后的清洗剂配方在实际生产线上做试验,结果表明能有效去除BTA、CuO晶粒及磨料SiO2,且基本无界面腐蚀。解决了一直难以解决的多层铜布线CMP后有效去除BTA的难题,且该清洗剂成分简单,成本低而且环保。     

低PH值螯合剂在TSV抛光液中的应用

硅通孔技术(Through Silicon Via,TSV)是一种新兴的技术,与传统的封装技术相比,硅通孔技术实现了芯片的微型化,并且使摩尔定律得以进一步扩展。化学机械抛光(CMP)是TSV技术中的关键步骤之一,低压低磨料低PH值是CMP抛光液的主要发展趋势。本文研究了含有FA / O II型螯合剂的抛光液和含有FA / O IV型螯合剂的抛光液在CMP过程中的影响。本实验中使用的抛光液都是碱性抛光液,并且不含任何抑制剂。对比实验结果我们可以知道不论是在铜膜的去除速率还是抛光后铜膜表面的粗糙度,低PH值的FA / O IV型螯合剂都明显优于FA / O II类螯合剂。