CN107154335A - 通用处理套件 - Google Patents

通用处理套件 Download PDF

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CN107154335A
CN107154335A CN201710124363.XA CN201710124363A CN107154335A CN 107154335 A CN107154335 A CN 107154335A CN 201710124363 A CN201710124363 A CN 201710124363A CN 107154335 A CN107154335 A CN 107154335A
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inner ring
process kit
thermo
contact pad
ring
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CN107154335B (zh
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O·茹贝尔
J·A·肯尼
S·斯利尼瓦萨恩
J·罗杰斯
R·丁德萨
V·S·阿楚沙拉曼
O·鲁赫尔
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Applied Materials Inc
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Abstract

本文所述实施方式一般涉及适合在半导体处理腔室中使用的处理套件,与常规处理套件相比,所述处理套件用单个边缘环减小边缘效应并加宽处理窗口。所述处理套件一般包括设置为邻近于并且围绕在等离子体腔室中的半导体基板周边的边缘环。所述基板和所述边缘环之间的间隙的尺寸小于约1000μm,并且所述基板和所述边缘环之间的高度差小于约(+/‑)300μm。所述环的电阻率小于约50Ohm‑cm。

Description

通用处理套件
技术领域
本公开的实施方式一般涉及半导体处理,并且更具体地涉及一种用于半导体处理腔室中的处理套件。
背景技术
在等离子体处理腔室中执行各种半导体制造工艺,诸如等离子体辅助的蚀刻或化学气相沉积。基板支撑件在半导体处理腔室内的处理位置处支撑基板。在所述半导体处理腔室内维持包括一或多种处理气体的等离子体区域,以对设置在所述基板支撑件上的基板执行半导体制造工艺。
等离子体鞘是由空间电荷形成的强电场的薄区域,所述等离子体鞘将等离子体与材料边界分隔。在等离子体蚀刻期间,等离子体鞘形成于等离子体和正被蚀刻的基板、半导体处理腔室的壁以及半导体处理腔室的与所述等离子体区域接触的所有其他部分(包括所述处理套件)之间。
等离子体鞘的厚度(d)由如下所示等式1表示:
d=(2/3)(E/i)1/2(2e/m)1/4(VP-VDC)3/4
(等式1)
在等式1中,“i”为离子电流密度,“ε”为真空介电常数,“e”为元电荷,“m”为离子质量,以及“VP”为等离子体电位。如图所示,等离子体鞘的厚度可通过调整等离子体参数(即源功率和偏压功率)来增加或减小,所述源功率和偏压功率分别影响离子电流“i”和“VDC”。在等离子体区域中产生的离子沿垂直于所述等离子体鞘的轨道在等离子体鞘中加速。因为等离子体鞘一般平行于基板的平面,所以穿过所述等离子体鞘的离子一般沿垂直方向冲击所述基板。相反地,等离子体鞘形状的扰动(例如由位于基板边缘的处理套件的存在引起)局部地改变离子通量,使得穿过等离子体鞘的离子沿非垂直方向冲击基板,从而产生蚀刻不均匀性。
因此,本领域中需要改进的处理套件。
发明内容
公开了一种适合在半导体处理腔室中使用的处理套件。在一个实施例中,处理套件包括边缘环。所述边缘环包括内环和外环。所述内环包括具有与第二表面相对的第一表面的非金属导电体。所述非金属导电体具有小于约50Ohm-cm的电阻率。所述内环进一步包括沿所述内环的内径设置的凹口。所述凹口具有上升小于约1200μm的垂直分量和在约1300μm与约2500μm之间延伸的水平分量。所述外环耦接到所述内环并且环绕所述内环的周边。所述外环包括具有与第四表面相对的第三表面的石英主体。
在另一实施例中,公开了用于对基板执行半导体处理的等离子体腔室。所述等离子体腔室包括基板支撑组件和处理套件。所述处理套件适合于邻近基板支撑组件使用并且耦接到所述基板支撑组件的凸缘。所述处理套件包括边缘环和导电构件。所述边缘环包括沿所述边缘环的内径设置的凹口。所述凹口具有上升小于约1200μm的垂直分量和在约1300μm和约2500μm之间延伸的水平分量。另外,所述导电构件耦接到所述边缘环。
在又一实施例中,适合在处理腔室中使用的处理套件包括边缘环、至少一个热接触垫和导电构件。所述边缘环环绕基板支撑组件的周边,所述基板支撑组件被设置在处理腔室中。所述边缘环包括内环和外环。所述内环设置为邻近于所述基板支撑组件并且包含非金属导电材料。所述内环进一步包括沿所述内环的内径设置的凹口,其中所述凹口具有上升小于约1200μm的垂直分量和在约1300μm和约2500μm之间延伸的水平分量。所述外环耦接到所述内环并且环绕所述内环的周边。所述外环包含石英材料。所述至少一个热接触垫耦接到所述内环并且设置在形成于所述内环中的槽内。另外,所述导电构件耦接到所述外环。
附图说明
因此,为了能够详细理解本公开的上述特征结构所用方式,可以参考各个实施方式更具体的描述上文所简要概述的本公开,所述实施方式中的一些示出于附图中。然而,应当注意,附图仅示出本公开的示例性实施方式,并且因此不应视为限制本公开的范围,且本公开可允许其他等效实施方式。
图1示出了根据本文所述实施方式的等离子体处理腔室的示意性剖面图。
图2A和图2B分别示出了图1的处理套件的示意性剖面图和示意性放大剖面图。
图3示出了图1的处理套件的示意性俯视图。
图4A和图4B示出了相对于偏压功率使用高源功率执行的氮化物蚀刻速率和相对于偏压功率使用低源功率执行的氮化物蚀刻速率的示意图表。
为了便于理解,在尽可能的情况下,使用相同的附图标记来标示图中共有的相同元素。可以预期一个实施方式的元素和特征可以有益地并入其他实施方式中而无须赘述。
具体实施方式
本文所述实施方式一般涉及适合在半导体处理腔室中使用的处理套件,与常规处理套件相比,所述处理套件用单个边缘环减小边缘效应。所述处理套件一般包括设置为邻近于并且围绕在等离子体腔室中的半导体基板的周边的边缘环。所述基板和所述边缘环之间的间隙尺寸小于约1000μm,并且所述基板和所述边缘环之间的高度差小于约(+/-)300μm。所述环的电阻率小于约50Ohm-cm。
如本文所述,“基板”或“基板表面”一般指对其执行处理的任何基板表面。例如,根据应用,基板表面可包含硅、二氧化硅、掺杂硅、硅锗、锗、砷化镓、玻璃、蓝宝石和任何其他材料(诸如金属、金属氮化物、金属合金和其他导电或半导电材料)。基板或基板表面亦可包含诸如二氧化硅、氮化硅、有机硅酸盐和碳掺杂氧化硅或氮化物材料的电介质材料。术语“基板”可进一步包括术语“晶片”。基板本身不限于任何特定大小或形状。尽管本文描述的实施方式一般参考圆形基板进行,但是根据本文描述的实施方式可以使用其他形状,诸如多边形、正方形、矩形、弯曲的或其他非圆形工件。
对处理腔室的一般描述
图1示出了在其中可使用本实施方式的半导体处理腔室100的一个实施例的示意性剖面图。所示出的半导体处理腔室100为适用于蚀刻或者化学气相沉积(chemical vapordeposition,CVD)的磁性增强等离子体腔室。
处理腔室100包括圆柱形侧壁102、圆形底壁104和圆形顶壁106。阳极电极108安装在顶壁106的底部并且可电接地。阳极电极108可经穿孔以充当气体入口,处理气体穿过所述气体入口进入半导体处理腔室100。半导体处理腔室100的壁102、壁104和壁106的每一个都为金属,尽管壁102、壁104、壁106的一些或全部可包括半导体或电介质材料。不为电介质的任意壁102、壁104、壁106可电接地并且充当阳极电极108的部分。
基板支撑组件120设置在处理腔室100中。基板支撑组件120具有面向阳极电极108的基本上平坦的前表面140。基板支撑组件120的前表面140在处理期间支撑基板110。基板支撑组件120可由半导体处理腔室100的底壁104支撑。基板支撑组件120具有金属基板支撑主体122,所述金属基板支撑主体122充当下文描述的阴极电极,但如果设置在基板支撑组件120内的另一电极被配置成作为阴极电极进行操作,则基板支撑主体122不需要为金属。
可通过机械夹具、真空、重力或通过静电力将基板110固定在基板支撑组件120上的适当位置。在一个实施例中,基板支撑组件120包括静电卡盘126,可激励静电卡盘126以在处理期间将基板110抵靠基板支撑组件120的前表面140牢固地固定。
静电卡盘126包括由电介质材料142围绕的至少一个卡紧电极124。静电卡盘126的电介质材料142使卡紧电极124与基板110并且与金属基板支撑主体122电绝缘,从而使得能够当卡紧电极124通电时产生对基板110的静电引力。用于操作静电卡盘126的功率由电源128供应。
支撑基板110的静电卡盘126的部分144的直径可小于基板110的直径(即,基板110略突出于支撑基板110的静电卡盘126的部分144的周边)。
基板支撑组件120进一步包括设置在静电卡盘126下方的基板支撑主体122。基板支撑主体122可为圆柱形形状并且可由诸如阳极化铝的金属材料组成。基板支撑主体122具有比静电卡盘126更大的半径以提供凸缘146来促进将静电卡盘126紧固到基板支撑主体122。
真空泵(未示出)将气体从处理腔室通过排气歧管130排出并且将腔室中的总气压维持在足够低的程度以促进等离子体的形成,例如在约10毫托至20托的范围内,其中在所述范围的下限端和上限端的压力分别更适于蚀刻处理和CVD处理。
在基板110的处理期间,将等离子体维持在被限定在基板110和阳极电极108之间的处理腔室100的区域148中。所述等离子体通过将处理气体混合物激发至等离子体状态来形成。所述等离子体可在处理腔室内产生(原位等离子体),或在另一腔室中产生(远程等离子体源)并且被泵送到所述处理腔室内。
射频(radio frequency,RF)电源132通过一或多个串联耦合电容器134连接到以下腔室部件中的一或多个:基板支撑主体122、卡紧电极124或附加电极(诸如线网),所述附加电极嵌入在静电卡盘126中。这些组件的任何一个连接到所述RF电源以共同组成所述处理腔室的阴极电极。在一个实施例中,基板支撑主体122连接到RF电源132以便充当阴极电极。
RF电源132在阴极电极和接地阳极电极108之间提供RF电压,其帮助供应用以维持等离子体所需的激发功率。相对于阳极电极和等离子体,施加到阴极的RF电压也在阴极电极上产生时均负DC偏压,这使离子化的处理气体成分加速朝向阴极电极,从而促进对基板110的处理。
在一个示范性实施方式中,由基板支撑组件120支撑的基板110可为200mm、300mm或450mm的硅晶片。标准200mm基板一般具有约725μm的厚度。标准300mm基板一般具有约775μm的厚度。标准450mm基板一般具有约925μm的厚度。
通用处理套件
图2A示出了适合在图1的半导体处理腔室100中使用的处理套件200的示意性剖面图。图3示出了图1的处理套件200的示意性俯视图。参看图2A和图3两者,处理套件200设置在半导体处理腔室100中以改进等离子体处理并在处理期间保护腔室部件。在一些实施例中,处理套件200可耦接到基板支撑组件120和/或由基板支撑组件120支撑或可邻近于基板支撑组件120使用。处理套件200进一步绕基板110的周边延伸和/或设置为邻近于基板110。
处理套件200包括边缘环202。边缘环202包括内环204和外环206。然而,可以预期的是,在一些实施例中,内环204和外环206可形成单个环。边缘环202环绕基板支撑组件120的周边150。边缘环202包括沿边缘环202和/或内环204的内径212设置的凹口210。
内环204设置为邻近于基板支撑组件120。内环204包括第一表面214和第二表面216,其中第二表面216与第一表面214相对。内环204由非金属和/或具有小于约100Ohm-cm(例如,小于约50Ohm-cm)的电阻率的导电材料制造。内环204可由碳化硅材料、硅材料、非金属材料、和/或它们的混合物和组合制造。
内环204进一步包括凹口210。在一些实施例中,凹口210在内环204的内径212中形成。凹口210包括由图2A中的参考箭头“V”表示的垂直分量。垂直分量V可具有小于约1500μm(例如,小于约1200μm)的上升。凹口210进一步包括由图2A中的参考箭头“H”表示的水平分量。水平分量H可具有在约1000μm和约3000μm之间延伸(例如,在约1300μm和约2500μm之间,诸如约1800μm)的长度(run)。凹口210可在处理期间支撑基板110和/或防止基板110运动。
图2B为图2A所示的边缘环202的凹口210的放大剖面图。为了不扰动在基板110的边缘处的等离子体鞘,处理套件200的尺寸可精确地形成在精密公差内。因而,基板110和边缘环202的内环204之间的间隙E的尺寸小于约1000μm,例如,小于约850μm,诸如小于约800μm。另外,边缘环202的内环204的高度F经选择成使得基板110的顶表面240和内环204的第一表面214大约位于相同的平面上。在一些实施例中,大约在相同平面中包括在由基板110的顶表面240形成的平面和由内环204的第一表面214形成的平面之间的垂直距离距彼此约(+/-)400μm内,例如,距彼此约(+/-)300μm内,诸如距彼此(+/-)200μm内。
返回到图2A和图3,外环206耦接到内环204,并且可环绕内环204的周边218。在一些实施例中,外环206可通过沿外环的内周边222形成的支撑凸耳220支撑内环204。另外,外环206包括第三表面224和第四表面226。第三表面224可与第四表面226相对。外环206可包含石英材料。
处理套件200可进一步包括至少一个热接触垫208。在一些实施例中,热接触垫208可为可选的。尽管在图2A中仅示出了一个热接触垫208的部分,但可预期的是,可使用多个热接触垫208,如图2B中所示。热接触垫208可由硅树脂(聚合物)材料制造。另外,热接触垫208和边缘环202可各自共用类似的热导率。热接触垫208的益处包括促进边缘环202和静电卡盘126之间良好的热接触。
热接触垫208可耦接到内环204。每个热接触垫208与内环204的第二表面216接触,并且在一些实施例中,每个热接触垫208可具有不连续的(即,分段的)环形状,如图3所示。因而,热接触垫208可包括类似于边缘环202的环形状,然而,所述热接触可能不完全绕边缘环202延伸。然而,可以预期的是,在一些实施例中为连续环并且具有连续环形状的一个热接触垫208可完全绕边缘环202延伸。然而,在其他实施例中,热接触垫208可为任何适合的形状。
另外,如图3所示,多个热接触垫208可与内环204接触。如图3中所示有四个热接触垫208,但可以预期,可以使用任意数目的热接触垫208。每个热接触垫208可促进在边缘环202和静电卡盘126之间的良好的热接触。
内环204的第二表面216可包括在第二表面中至少部分地形成的至少一个槽228。每个槽228可容纳热接触垫208的相应一者。因而,在内环204的第二表面216中形成的热接触垫208的数目和槽228的数目可为相同的。每个热接触垫208可完全地容纳在每个槽228内,然而,在一些实施例中,每个热接触垫208可部分地从相应的槽228延伸出而突出到内环204的第二表面216外。每个槽228保护相应热接触垫208并且最小化热接触垫208与其他部件的干扰。
在一些实施例中,处理套件200可进一步包括导电构件230。导电构件230可耦接到外环206的第四表面226。在一些实施例中,外环206可包括在第四表面226中形成的通道232。导电构件230可至少部分地设置在通道232内,使得外环206耦接到导电构件230。
执行测试并且结果指示通过使用本文公开的处理套件最小化了离子聚焦和散焦效应,如图4A和图4B的示意图所示。如进一步示出,所述基板的表面相对于所述环的顶表面的位置对最小化基板边缘处的等离子体鞘的扰动是关键的。如果将所述边缘环加工为使得所述基板位于所述边缘环的平面上方,则所述等离子体鞘可向外弯曲。离子垂直于所述等离子体鞘移动,并且因此偏离基板边缘,这使得蚀刻速率减小。另一方面,如果将所述边缘环加工为使得所述基板位于所述环的平面下方,则所述鞘可向内弯曲从而将离子聚焦在所述晶片的边缘上,这使得蚀刻速率增大。使用本文公开的处理套件将所述基板定位于与所述边缘环相同的平面上,并且因此最小化等离子体鞘的弯曲。此外,所述等离子体鞘的弯曲能力取决于所述等离子体鞘的厚度,以及因此取决于等离子体条件——主要为源功率和偏压功率(参照等式1)。图4A和图4B示出,当使用相对于偏压功率(例如,在约50瓦特和约500瓦特之间)的高源功率(例如,约1000瓦特以上)或使用相对于偏压功率(例如,在约50瓦特和约500瓦特之间)的低源功率(例如,约500瓦特以下)测试本公开的处理套件时,所述处理套件的几何形状最小化边缘效应,而不管所述等离子体条件如何。
本公开的益处包括减小在基板边缘处的等离子体鞘的扰动的处理套件。所述边缘环可包括导电环和非导电环,所述导电环和非导电环都可被加工为与基板齐平。因而,处理套件作用以减小归因于不均匀的等离子体鞘的等离子体蚀刻中的变化,从而改进所述处理均匀性。
总体来说,本文描述的实施方式一般涉及适合在半导体处理腔室中使用的处理套件,与常规处理套件相比,所述处理套件使用单个边缘环减小边缘效应并加宽处理窗口。所述处理套件一般包括设置为邻近于并且围绕在等离子体腔室中的半导体基板的周边的边缘环。所述基板和所述边缘环之间的间隙的尺寸小于约1000μm,并且所述基板和所述边缘环之间的高度差小于约(+/-)300μm。所述环的电阻率小于约50Ohm-cm。
尽管上述内容针对本公开的实施方式,但也可在不脱离本公开的基本范围的情况下设计本公开的其他和进一步的实施方式,并且本公开的范围由随附的权利要求书确定。元件符号列表
100 半导体处理腔室
102 圆柱形侧壁
104 底壁
106 顶壁
108 阳极电极
110 基板
120 基板支撑组件
122 基板支撑主体
124 卡紧电极
126 静电卡盘
128 电源
130 排气歧管
132 射频电源
134 串联耦合电容器
140 前表面
142 电介质材料
144 部分
146 凸缘
148 区域
150 周边
200 处理套件
202 边缘环
204 内环
206 外环
208 热接触垫
210 凹口
212 内径
214 第一表面
216 第二表面
218 周边
220 支撑凸耳
222 内周边
224 第三表面
226 第四表面
228 槽
230 导电构件
232 通道
240 顶表面

Claims (20)

1.一种适合在半导体处理腔室中使用的处理套件,所述处理套件包括:
边缘环,所述边缘环包括:
内环,所述内环包括:
非金属导电体,所述非金属导电体具有与第二表面相对的第一表面,所述非金属导电体具有小于50Ohm-cm的电阻率,其中所述内环包括沿所述内环的内径设置的凹口,其中所述凹口具有上升小于1200μm的垂直分量和在1300μm与2500μm之间延伸的水平分量;和
外环,所述外环耦接到所述内环并环绕所述内环的周边,所述外环包括:
石英主体,所述石英主体具有与第四表面相对的第三表面。
2.如权利要求1所述的处理套件,其特征在于,所述内环包含碳化硅材料、硅材料、非金属材料、或它们的组合和混合物。
3.如权利要求1所述的处理套件,进一步包括:
至少一个热接触垫,所述至少一个热接触垫与所述内环的第二表面接触。
4.如权利要求3所述的处理套件,其特征在于,所述热接触垫和所述边缘环共用类似的热导率。
5.如权利要求3所述的处理套件,其特征在于,所述至少一个热接触垫具有不连续的环形状。
6.如权利要求3所述的处理套件,其特征在于,所述热接触垫包含硅树脂材料。
7.如权利要求1所述的处理套件,其特征在于,所述内环的所述第二表面包括至少部分在所述第二表面中镗过的至少一个槽,其中至少一个热接触垫容纳在所述槽内,并且其中所述至少一个热接触垫包含硅树脂材料。
8.如权利要求1所述的处理套件,进一步包括耦接到所述外环的所述第四表面的导电构件。
9.如权利要求8所述的处理套件,其特征在于,所述外环包括在所述第四表面中形成的通道,并且其中所述导电构件至少部分地被设置在所述通道内。
10.一种用于对基板执行半导体处理的等离子体腔室,所述等离子体腔室包括:
基板支撑组件;和
处理套件,所述处理套件适合于邻近所述基板支撑组件使用并且耦接到所述基板支撑组件的凸缘,所述处理套件包括:
边缘环,所述边缘环包括沿所述边缘环的内径设置的凹口,其中所述凹口具有上升小于1200μm的垂直分量和在1300μm和2500μm之间延伸的水平分量;和
导电构件,所述导电构件耦接到所述边缘环。
11.如权利要求10所述的等离子体腔室,其特征在于,所述边缘环包括:
内环,所述内环设置成邻近所述基板支撑组件,所述内环包含非金属导电材料;
外环,所述外环耦接到所述内环并环绕所述内环的周边,所述外环包含石英材料。
12.如权利要求11所述的等离子体腔室,其特征在于,所述内环具有小于50Ohm-cm的电阻率。
13.如权利要求11所述的等离子体腔室,其特征在于,所述内环包含碳化硅材料、硅材料、或它们的组合和混合物。
14.如权利要求10所述的等离子体腔室,进一步包括:
至少一个热接触垫,所述至少一个热接触垫耦接到所述边缘环并且被设置在形成于所述边缘环中的槽内。
15.如权利要求14所述的等离子体腔室,其特征在于,所述至少一个热接触垫包括硅树脂材料。
16.如权利要求10所述的等离子体腔室,其特征在于,所述导电构件至少部分地设置在形成于所述边缘环中的通道中。
17.如权利要求14所述的等离子体腔室,进一步包括第二热接触垫、第三热接触垫和第四热接触垫,其中每个热接触垫都被设置在形成于所述边缘环中的槽中。
18.一种适合在处理腔室中使用的处理套件,所述处理套件包括:
边缘环,所述边缘环环绕被设置在所述处理腔室中的基板支撑组件的周边,所述边缘环包括:
内环,所述内环被设置成与所述基板支撑组件相邻,所述基板支撑组件包括非金属导电材料和沿所述内环的内径设置的凹口,其中所述凹口具有上升小于1200μm的垂直分量和在1300μm和2500μm之间延伸的水平分量;
外环,所述外环耦接到所述内环并且环绕所述内环的周边,其中所述外环包含石英材料;
至少一个热接触垫,所述至少一个热接触垫耦接到所述内环并且设置在形成于所述内环中的槽内;和
导电构件,所述导电构件耦接到所述外环。
19.如权利要求18所述的处理套件,其特征在于,所述内环包含碳化硅材料、硅材料、非金属材料、或它们的组合和混合物。
20.如权利要求18所述的处理套件,其特征在于,每个热接触垫包含硅树脂材料。
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