Study on low damage engraving of ultra-fine/high aspect ratio hole for ULSI process

ULSI工艺超细/高深宽比孔低损伤雕刻研究

• 批准号: 11555179
• 负责人: HORIIKE Yasuhiro
• 金额: $ 8.9万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11555179/
• 关键词: Flow-FET; ultra high aspect ratio; dry etching; down flow; dry cleaning; DNA electrophoresis; pillar chi@; Bosch method; コンタクト孔底部損傷; フロロカーボン; 壁との相互作用; 超高圧透過型電子顕微鏡; ビィア孔; Cu配線; コンタクトホール; プラズマエッチング; レジスト側壁; ダメージ層; 水素添加; エッチ・ストップ

This study was carried out by the purpose that SiO2 contact hole in the ULSI device process was engraved satisfying high aspect ratio, low damage and good reproducibility. The study consists of ultra-high voltage TEM observation of contact holes, interaction between fluorocabon plasmas and an inner wall of a reactor and a sidewall protection etching. At first, bottoms of 0.1μm diameter holes engraved by the magnetron RIE employing were observed by a cross sectional TEM. The spot-like defects were observed, while these defects were annealed out at 500℃. This shows that serious defects are not induced so much. However, it is reported that actual contact resistance for the as-etched bottom surface is increased. This implies requirement of further efforts to improve the defects reduction. Next, to study the wall interaction of fluorocarbon species in C_4F_8 ICP (inductively coupled plasma), an ICP reactor equipped with a small scaled QMS, OES and a temperature controlled metal stage was de … More veloped and dependences of stage temperature, distance from the stage, bias voltage added to the stage and residence time on densities of fluorocarbon species near the stage surface. As a result, total densities of CF_x(x=l-3) radicals increased at any distance with increasing stage temperature. This increase was larger as the gap was closer to the stage surface and especially CF_3 radicals indicated the most increase. In addition, Variations of radical densities with change in temperatures could be suppressed by shorter residence time. Finally, we studied a new method achieving high aspect ratio feature by protection of the mask side wall erosion during etching. For the goal, we preserved the resist mask feature by deposition of species on the resist side wall at a glancing angle. As a result, reduction of the mask thickness and expansion of the opening width could be minimized, thus engraving holes with 0.15μm diameter and 15 of aspect ratio successfully. The method was applied to etching of ultra-high aspect ratio Si trench by improving the Bosch method. To transfer the result to fabricate a bio chip, the Si surface was oxidized and an electroosmosis pump was developed. Furthermore, a new "Flow-FET" was fabricated by forming a Au electrode on the back side of the Si substrate. Consequently, positive and negative Zeta potentials were controlled freely by adding 0 and 5 volts to the electrode. Less

本研究的目的是在ULSI器件工艺中刻制出高深宽比、低损伤、重复性好的SiO_2接触孔。该研究包括接触孔的超高压透射电子显微镜观察、氟碳等离子体与反应堆内壁的相互作用以及侧壁保护腐蚀。首先，采用磁控刻蚀技术对直径为0.1μm的孔底进行了横截面观察。观察到了斑点状缺陷，这些缺陷在500℃的温度下被完全消除。这表明，严重的缺陷并没有诱发那么多。然而，据报道，蚀刻时底部表面的实际接触电阻增加了。这意味着需要进一步努力改进缺陷减少。其次，为了研究C_4F_8电感耦合等离子体中氟碳化合物的壁面相互作用，采用小型QMS、OES和温控金属段组成的电感耦合等离子体反应器De…阶段温度、距阶段的距离、添加到阶段的偏置电压和停留时间对阶段表面附近的氟碳化合物的密度有更大的发展和依赖关系。结果表明，CFx(x=L-3)自由基的总密度随阶段温度的升高而增加。间隙越靠近舞台表面，增加幅度越大，尤其是CF3自由基的增加幅度最大。此外，较短的停留时间可以抑制自由基密度随温度变化的变化。最后，我们研究了一种新的方法，通过保护刻蚀过程中掩模侧壁的侵蚀来实现高纵横比特征。为了达到这个目的，我们通过以掠视的角度在抗蚀剂侧壁上沉积物种来保留抗蚀剂掩模特征。结果，掩模厚度的减小和开口宽度的扩大都可以最小化，从而成功地雕刻出直径为0.15μm、长宽比为15的孔。通过对Bosch方法的改进，将该方法应用于超大长径比硅槽的刻蚀。为了将结果转化为生物芯片，对硅表面进行了氧化处理，并研制了电渗泵。此外，通过在硅衬底背面形成Au电极，制作了一种新的“Flow-FET”。因此，通过向电极添加0和5伏，可以自由地控制正和负Zeta电位。较少

项目成果

堀池靖浩(分担): "次世代ULSIプロセス技術"リアライズ社. 825 (2000)

Yasuhiro Horiike（撰稿人）：“下一代 ULSI 工艺技术”Realize Inc. 825 (2000)

堀池靖浩(分担): "半導体大事典"工業調査会. 2011 (1999)

Yasuhiro Horiike（撰稿人）：《半导体百科全书》工业研究组 2011 年（1999 年）。

Hiroyuki Yoshiki, Yasuhiro Horiike: "Capacitively Coupled Microplasma Source on a Chip at Atmospheric Pressure"Jpn. J. Appl.Phys.. 40・4A. L360-L362 (2001)

Hiroyuki Yoshiki、Yasuhiro Horiike：“大气压下芯片上的电容耦合微等离子体源”Jpn. Appl.Phys.. 40・4A (2001)。

Hiroyuki Yoshiki, Akio Oki, Hiroki Ogawa, Yasuhiro Horiike: "Generation of a capacitively coupled microplasma and its application to the inner-wall modification of a poly(ethylene terephthalate) capillary"J. Vac. Sci. Technol.. A20(1). 24-29 (2002)

Hiroyuki Yoshiki、Akio Oki、Hiroki Okawa、Yasuhiro Horiike：“电容耦合微等离子体的生成及其在聚对苯二甲酸乙二醇酯毛细管内壁改性中的应用”J。

Y.Chinzei,et al.: "High aspect ratio SiO_S etching with high resist selectivity improved by Addition of organaosilane to tetrafluoroethyl trifluoromethyl ether"J.Vac.Sci.Technol.. A18(1). 158-165 (2000)

Y.Chinzei 等人：“通过将有机硅烷添加到四氟乙基三氟甲基醚中，提高了具有高抗蚀剂选择性的高纵横比 SiO_S 蚀刻”J.Vac.Sci.Technol.. A18(1)。