CN115995426A - 用于形成互连结构的方法 - Google Patents

用于形成互连结构的方法 Download PDF

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CN115995426A
CN115995426A CN202211265933.4A CN202211265933A CN115995426A CN 115995426 A CN115995426 A CN 115995426A CN 202211265933 A CN202211265933 A CN 202211265933A CN 115995426 A CN115995426 A CN 115995426A
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G·西布罗特
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Interuniversitair Microelektronica Centrum vzw IMEC
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Abstract

提供了一种用于形成用于第一晶体管和第二晶体管的互连结构的方法,其中第一晶体管包括水平延伸的第一沟道部分(112),且所述第二晶体管包括水平延伸的第二沟道部分(122),并且其中所述沟道部分在基板上被堆叠在彼此上方。该方法包括:形成在第二沟道部分的旁边和下方延伸的导电线(130);在导电线上形成用于电接触第一沟道部分的第一垂直互连结构(132);以及从背面减薄基板以从下方露出导电线。该方法还包括形成从下方露出第二沟道部分的通孔(146);用导电材料填充所述通孔以形成第二垂直互连结构(142);以及在第二垂直互连结构上形成导电结构(140)。

Description

用于形成互连结构的方法
技术领域
本发明概念一般涉及半导体加工,且尤其涉及互连结构的形成。
背景技术
为了提供更具面积效率的电路设计,正在开发垂直堆叠的半导体器件。一个示例是所谓的互补场效应晶体管(FET)设计,其中两个水平沟道晶体管相互堆叠,使得第一晶体管的水平沟道部分被布置在另一晶体管的水平沟道部分之上。
然而,垂直堆叠设计的发展给形成用于互连不同垂直水平处的器件和结构的电气互连结构带来了挑战。可布置在绝缘材料层中的互连结构可包括不同互连层上的水平导电路径或线路,通过垂直延伸于各层之间的导电通孔互连。由于导电通孔的长度随由该通孔互连的各层的垂直间隔而变化,因此不同通孔之间的电阻也有变化。由于电阻往往随着通孔长度的增加而增加,因此平衡不同通孔之间的电阻并避免某些互连层之间的电阻过高是有挑战性的。
发明内容
本发明概念的一个目的是提供一种允许互连结构优选地具有经改进的电阻特性的替换方法和器件。可从下文中理解其他目的或另外一些目的。
根据本发明概念的一方面,提供了一种用于形成垂直地堆叠在基板上的第一晶体管和第二晶体管的互连结构的方法,其中第一晶体管包括水平延伸的第一沟道部分,且第二晶体管包括水平延伸的第二沟道部分,并且其中第一沟道部分被布置在第二沟道部分的上方。该方法包括:
在基板中形成在第二沟道部分的旁边和下方延伸的导电线;
在导电线上形成用于电接触第一沟道部分的第一垂直互连结构;
从背面减薄基板以从下方露出导电线;
形成从下方露出第二沟道部分的通孔;
用导电材料填充通孔以形成第二垂直互连结构;以及
在第二垂直互连结构上形成导电结构。
根据第二方面,提供了一种半导体器件,该半导体器件包括垂直地堆叠在基板上的第一晶体管和第二晶体管,其中第一晶体管包括水平延伸的第一沟道部分,且第二晶体管包括水平延伸的第二沟道部分,并且其中第一沟道部分被布置在第二沟道部分的上方。该半导体器件还包括布置在基板中并且在第二沟道部分的旁边和下方延伸的导电线,布置在导电线上且用于接触第一沟道部分的第一垂直互连结构,布置在第二沟道部分下方的导电结构,以及在第二沟道部分和导电结构之间延伸的第二垂直互连结构。
本发明技术允许用于形成互连结构的替换技术,其中第一沟道部分被互连到第一导电线(第一导电线也可以称为第一埋入式功率轨),借助于形成在埋入式功率轨顶部上并一直延伸到第一沟道部分的垂直水平的第一垂直互连结构。第一垂直互连结构可以设置有允许获得特定电阻的横向尺寸。优选地,第一垂直互连结构的横向尺寸可以大于传统通孔结构的横向尺寸,以降低电阻。
本发明技术还允许借助于第二垂直互连结构从下方接触第二沟道部分。此后,第二导电线(也可称为第二埋入式互连)可被形成在第二垂直互连结构上,并因此可与第二沟道部分对准。与第一垂直互连结构类似,第二垂直互连结构的尺寸可以允许获得特定的电阻。
将明白,第一和第二沟道部分水平地(即沿着基板的延伸部的主平面)延伸,并且可以在与基板的延伸部的主平面正交的垂直方向上布置在彼此上方。此外,将明白,第一和第二沟道部分布置在基板的同一侧上。第一和第二沟道部分中的每一者可以包括一层或若干层,诸如纳米片,这取决于要形成的所得晶体管器件的设计和配置。此外,如本文所使用的,术语“沟道部分”可理解成包括至少部地分封装沟道部分的互连结构。因此,上述第一/第二垂直互连结构可被布置成经由至少部分地封装相应沟道部分的栅极结构或源极/漏极互连结构来电接触第一/第二沟道部分。
术语“基板”可理解成例如硅或介电材料的底层,其上布置有第一和第二沟道部分。
第一导电线也称为埋入式功率轨,可以通过在由第一和第二沟道部分形成的堆叠旁边的位置处将凹槽或沟槽蚀刻在基板中并用导电材料填充该凹槽来形成。在一些示例中,第一导电线可以形成在延伸穿过绝缘层(诸如布置在基板上方的层间电介质ILD)的沟槽中。所得的导电线由此可以被部分地布置在基板中,部分地布置在绝缘层中。此外,将明白,虽然第一导电线的至少底部可以被埋在基板中,但导电线可以具有垂直延伸部,从而允许导电线的上部被布置在与第二沟道部分相同的垂直水平处或布置在其上方。
在一些示例中,第一导电线可以被布置在由第一和第二沟道部分形成的堆叠的两侧上。
第一导电线可以在形成第一和第二沟道部分之后,例如通过借助于一系列光刻和蚀刻步骤对基板(以及可能布置在基板上的任何绝缘层)进行图案化,来被形成。在替换示例中,第一导电线或其部分可以在形成第一和第二沟道部分的堆叠之前被形成。在后一情形中,第一导电线例如可以在沉积从中形成第一和第二沟道部分的层之前被形成。
第一垂直互连结构可以通过在覆盖第一和第二沟道部分以及第一导电线的堆叠的绝缘层中蚀出凹槽或沟槽来被形成。绝缘层可以被向下蚀刻直至第一导电线以露出其至少一部分,诸如沟道部分的栅极结构,从而允许第一导电线与沉积在凹槽中的导电材料电接触,以形成第一垂直互连结构。第一垂直互连结构的尺寸和配置可以取决于要实现的所需电阻来选择,这将在下文更详细地描述。
第二沟道部分连接到的导电结构可通过翻转基板(即将其倒置)从下方形成,并从背面将基板减薄以从下方露出导电线。导电结构和第二垂直互连可以在分开的工艺中被形成或者在共同的沉积工艺中被形成,如下面也将进一步详细讨论的。此外,取决于互连结构在后续的后段制程BEOL工艺中将要使用的方式,导电结构可形成类似于上述导电线的线路或插头。
因此,将明白,在本公开的上下文中,可以根据基板的正面和背面来描述基板,其中第一和第二沟道部分布置在正面,并且从背面进行的加工可以理解为与在其上布置第一和第二沟道部分的一侧相对的一侧的加工。“从背面”加工也可以称为“从下方”,无论基板是否翻转。
可以沉积绝缘层以覆盖第一导电线以及第一和第二沟道部分。随后可以在绝缘层中蚀出沟槽以露出第一导电线以及第一和第二沟道部分。此后,在用导电材料填充沟槽以形成与第一沟道部分接触的第一垂直互连结构之前,可以在第一和第二沟道部分的侧壁处形成隔墙(spacer)。
沟槽可以借助于一系列光刻和蚀刻步骤来限定,并且沟槽的横向宽度和长度定义了所得的垂直互连结构的横截面。例如,增加横截面的面积可帮助降低垂直互连结构的电阻。沟槽可以在由第一和第二沟道部分形成的堆叠的一侧处被形成,或者优选地在堆叠的两个相对侧处被形成,以便容纳整个堆叠。可以提供隔墙以将第一互连结构与第二沟道部分分隔开。因此,隔墙可以由介电材料形成,该介电材料提供在第二沟道部分与第一垂直互连结构的导电材料之间的电绝缘。例如,隔墙可以由氧化物(诸如氧化硅)形成,并且可以作为共形层提供,该共形层随后受到各向异性蚀刻,从而在沟槽的垂直侧壁上限定隔墙,同时暴露出第一导电线和至少第一沟道部分的顶部。优选地,隔墙垂直凹陷以露出第一沟道部分的侧壁的至少一部分,从而增加导电材料和第一沟道部分之间的接触表面。
可沉积导电材料以至少部分地从上方接触第一沟道部分,和/或在第一沟道部分的未被隔墙覆盖的露出侧部分处。
本技术可以与传统的通孔形成相对比,在传统通孔形成中,对准挑战和纵横比限制有缩短第二沟道部分的风险。通过对相对较大的沟槽进行开口,垂直互连结构和第二沟道部分之间的最小横向间隔可由隔墙的厚度来限定。由于隔墙可以通过例如共形沉积工艺形成,因此可以按更准确和精准的方式控制该间隔。
结合层可以被形成在第一垂直互连结构上方。结合层可被用于结合载体晶片,从而允许基板倒置以便于加工第二垂直互连结构和导电结构,从下方互连第二沟道部分。
加工第二垂直互连结构可涉及在基板背面形成凹槽或沟槽,其中沟槽可与第二沟道部分对准。可以在沟槽的底部形成通孔,从而使第二沟道部分的一部分暴露出来,以允许第二互连结构接触它。然后,通孔可由导电材料填充,从而形成第二垂直互连结构。在一些示例中,可沉积导电材料以也填充沟槽,从而同时也形成导电结构(也称为第二埋入式功率轨)。与第一垂直互连结构类似,通孔的横向尺寸可以限定第二垂直互连结构的横截面积并从而影响其电阻。由于第二沟道部分是布置在更靠近基板背面的那一个,所以第二垂直互连结构可以比第一垂直互连结构短并且因此可具有更小的横截面积。
优选地,互连第一沟道部分的导电线和互连第二沟道部分的导电结构可以被布置在同一垂直水平上。这可以理解成每个结构的至少一部分被布置在同一水平上,诸如举例而言在基板背面处露出的相应部分。这可便于后续的后段制程BEOL加工。
第一和第二沟道部分可以通过外延地形成包括交替的沟道材料和牺牲材料层的堆叠结构来被形成。然后,可以将堆叠结构图案化成鳍,并从鳍的至少一部分移除牺牲材料层,以便剩余的沟道材料部分形成第一和第二沟道部分。沟道材料和牺牲材料可以相对于彼此是具有蚀刻选择性的,以允许释放沟道部分。在一些示例中,沟道材料可以由硅形成,而牺牲材料由硅锗形成,或反之。
沟道部分可以包括一个或多个栅极层,例如被布置在栅极层堆叠中,从而形成栅极结构。栅极结构可至少部分地封闭沟道部分。栅极层可以包括栅极电介质(例如包括低k电介质和/或高k电介质)以及一个或多个导电栅极层或金属层。例如,栅极层可以在沟道部分释放之后或者在用于形成第一垂直互连结构的沟槽形成之后被沉积。
基板可以包括蚀刻停止层,在形成第一导电线的沟槽时充当蚀刻停止。在一示例中,基板可以由硅形成,而蚀刻停止层由硅锗形成。蚀刻停止层可以在减薄工艺中被去除,在减薄工艺中,第一导电线从背面露出。
附图说明
通过参考附图的说明性和非限制性的以下详细描述,将更好地理解本发明构思的以上以及其他目的、特征和优点。在附图中,除非另有说明,否则相似的附图标记将用于相似的元件。
图1-10解说了用于形成互连结构的方法。
具体实施方式
现在将参考附图1-10描述用于形成适用于例如半导体器件的互连结构的方法。该方法将结合形成由鳍结构形成的相应水平地布置的场效应晶体管FET的第一和第二沟道部分的互连结构来描述。然而,将注意,该方法通常可适用于形成垂直地堆叠的导电结构的互连结构,诸如半导体器件触点(例如源极/漏极触点)。
参考图1,示出了中间结构或器件的垂直横截面。该结构可以横向地或水平地延伸超过所示部分。除非另外指明,该部分的延伸穿过该结构的所示平面在所有附图中是共用的。注意到,所示元件的相对尺寸,尤其是各层的相对厚度仅是示意性的,并且可出于阐示清楚目的与物理结构不同。此外,将明白,可能省略了其他特征和层,并且附图中可只包括与解说如所附权利要求中所定义的本发明概念相关的那些元素。
图1示出了堆叠结构,该堆叠结构包括用于相应晶体管器件的第一沟道部分112和第二沟道部分122,在操作期间,该晶体管器件沿水平方向(在该附图的平面外)传导电流通过沟道部分。第一沟道部分112和第二沟道部分122垂直地堆叠在基板100上,其中第一沟道部分122布置在第二沟道部分122上方,如从基板100沿法线方向看到的。
在本示例中,沟道部分112、122可以由堆叠结构102形成,该堆叠结构包括交替的形成相应的沟道部分112和122的沟道材料层以及布置在其间的牺牲材料106层。例如,层堆叠102可以通过外延生长来形成,诸如包层外延工艺,并被图案化成例如图1所示的鳍。鳍可以例如用光刻和蚀刻步骤的序列形成,也称为光刻-蚀刻序列。光刻-蚀刻序列通常包括在要被图案化的层(即“目标层”)上形成光致抗蚀剂掩模层。可以在光致抗蚀剂层中通过光刻来限定图案(例如,开口、沟槽或线的图案),并随后在将经图案化的光致抗蚀剂膜用作蚀刻掩模的同时,通过蚀刻将其转移到目标层中。此后,可以从目标层剥离光致抗蚀剂层。沟道材料和牺牲材料可被选择成允许选择性地去除牺牲材料,例如借助于选择性蚀刻。沟道材料可以例如由Si形成,而牺牲材料由SiGe形成。由于SiGe和Si可以按不同的蚀刻速率被蚀刻,所以蚀刻速率的对比可被用来通过选择性地去除中间的牺牲层106来释放沟道部分112、122。
基板100例如可以是Si基板,其上可以形成沟道材料层和牺牲材料层的堆叠结构。出于本公开的目的,沟道材料层可被视为布置在基板的正面,其中第一沟道部分112布置在第二沟道部分122上方,因此第二沟道部122位于第一沟道部分122和基板100的上表面之间。
在图2中,在第一和第二沟道部分112、122的相应侧处形成了一对导电线130。虽然本附图解说了两个导电线130,但将明白,本发明概念也适用于不对称配置,例如包括单个导电线130。在一些示例中,导电线路130可以称为埋入式功率轨。导电线130可以形成于在基板100中延伸的沟槽中,并且在一些示例中,可以沿着第一和第二沟道部分112、122的至少一部分形成。沟槽可以例如被向下蚀刻到蚀刻停止层104。如本附图所示,导电线130可以垂直地布置在第一沟道部分112的下方和横向侧边,并且优选地也在第二沟道部分122的下方和旁边。此外,导电线130还可以至少部分地在布置在基板100上方的绝缘层150(例如层间电介质ILD)中延伸。导电线130可分两步形成,其中导电线130的底部部分形成于基板100中的沟槽中,而导电线130的其余部分形成于绝缘层150中的沟槽中。或者,导电线230是在单个填充工艺中形成的,在该填充工艺中,沟槽被形成于绝缘层150中并一直延伸到基板100中。导电线130可以包括一个或若干个层,诸如举例而言布置在基板100和形成导电线130的导电材料之间的阻挡层136。
绝缘层150可以是介电层,诸如氧化硅层或某一其他常规低k介电层。作为一个示例,绝缘层150可以通过化学气相沉积(CVD)来被沉积。
第一和第二沟道部分112、122可包括沟道部分互连结构134,和/或至少部分被沟道部分互连结构134封装。例如,沟道部分互连结构134可以被布置在晶体管结构的源极/漏极部分处,或者在相应的沟道部分112和122处形成栅极结构134。栅极结构134可以包括一个或多个栅极层,这取决于沟道部分112、122构成其一部分的晶体管结构的类型和配置。例如,栅极层可以形成包括栅极介电层的栅极层堆叠,栅极介电层由任何常规栅极介电材料形成,诸如HfO2、ZrO2、Al2O3或其他一些高-k介电材料。栅极介电材料可以通过任何常规沉积工艺(例如通过ALD)来被沉积成共形薄膜。栅极层还可以包括至少第一导电栅极层,该第一导电栅层随后被形成在栅极介电层上。第一导电栅极层可以由有效功函数金属(EWF)形成。例如,第一导电栅极层可以由一个或多个p型EWF金属(诸如TiN、TaN、TiTaN)或一个或多个n型EWF金属(诸如Al、TiAl、TiC或TiAlC)或复合层(诸如TiN/TiAl或TiN/TaN/TiA1)形成。第一导电栅极层可通过任何常规沉积工艺(例如通过ALD、CVD或PVD)来被沉积。栅极层还可包括第二导电栅极层,例如W、Al、Co、Ni、Ru或者两种或更多种所述材料的合金,以提供具有所需电属性的栅极电极。第二导电栅极层可通过任何常规沉积工艺(例如通过CVD)或通过电镀来被沉积。
图3示出了在绝缘层中形成沟槽152以露出导电线130以及第一和第二沟道部分112、122后,图2中的布置。例如,沟槽152可以使用如上所述的光刻-蚀刻序列来被形成。在本示例中,如果导电线130被布置在沟道部分112、122的堆叠的相应侧上,则沟槽可被布置成在沟道部分112、122的堆叠的两侧上横向地延伸,以允许两个导电线130在沟槽152的底部处被暴露出。在图4和图5中,隔墙154形成于第一和第二沟道部分112、122的侧壁处。例如,隔墙154可以由绝缘材料形成,例如氧化物,其可被共形地沉积在沟槽152中。如图4所示,共形绝缘材料层因此可以覆盖沟槽152的横向和水平表面这两者。为了形成隔墙154,绝缘材料层可以经受各向异性蚀刻,以暴露出水平结构,诸如沟槽152底部中的导电线130的顶面以及第一沟道部分112的顶面,同时将绝缘隔墙154留在例如第二沟道部分122的垂直侧壁上。因此,隔墙154可以向第二沟道部分122提供电绝缘。
在图6中,沟槽152已被填充导电材料,形成了第一垂直互连结构132。因此,第一垂直互连结构132可以从导电线130一直延伸到第一沟道部分112。至少部分地封装了第一沟道部分112的栅极结构134可以由第一垂直互连结构132至少从上方接触,并且还可以从第一沟道部分112的侧壁的未被隔墙154覆盖的部分处接触。因此,第一垂直互连结构132在第一沟道部分(或顶部沟道部分)112和导电线130(也称为顶部埋入式功率轨)之间提供电互连。同时,隔墙154可以防止第二沟道部分122与在第二沟道部122旁边经过的第一垂直互连132接触。
例如,导电线130和第一垂直互连结构132可以在镶嵌类工艺中形成,其中沟槽(诸如沟槽152)被填充了导电材料(例如钨)、通过例如化学机械抛光来凹陷、并由例如氧化物的绝缘层来覆盖。图6中示出了所得的结构。
在随后的加工中,例如后段制程BEOL部分,金属化层170可被添加在第一沟道部分112和第一垂直互连132的上方,如图7所示。为了允许从下方(即从背面)继续进行加工,基板100可以翻转并结合到载体晶片162。在图7的示例中,基板100优选地借助于布置在基板100和载体晶片161之间的结合层160来面朝下地被结合到载体晶片162。BEOL金属化层170是出于示例目的来示出的。如图7中进一步所示,基板100可以从背面减薄,优选地减薄到蚀刻停止层104,然后进行平面化步骤(诸如CMP)以从下方露出导电线130。图8中示出了所得的结构。
在图9中,剩余的基板材料已被移除,优选地是在利用基板材料和周围绝缘层150之间的蚀刻选择性的蚀刻工艺中进行。如本附图所示,形成了通孔或凹槽144,其与第二沟道部分122对准。凹槽144可以具有如下限定的形状:在第一横向方向上,在两个导电线130之间,由先前移除的基板材料的横向延伸部(例如,对应于图1中所示的鳍的宽度)来限定,并且在平行于导电线130的第二横向方向上,由光刻工艺限定。
在凹槽144的底部,可以形成通孔146,向下延伸到至少部分封装了第二沟道部分122的栅极结构134。因此,通孔146可被蚀穿绝缘材料以露出底层的第二沟道部分122,并允许其与第二垂直互连结构接触,如图10所示。第二垂直互连结构142可由(例如通过镶嵌式工艺)沉积在通孔146并延伸至凹槽144的导电材料形成。在一些示例中,凹槽144可由与通孔146相同的材料并在同一加工步骤中填充,但在其他示例中,可由分开的材料和/或工艺填充。图10所示的经填充凹槽144形成导电结构或第二埋入式功率轨,其可以布置在与导电线130类似的垂直水平并提供到第二沟道部分122的类似互连。
图10所示的所得互连结构允许第一沟道部分112通过(在本示例中是两个)导电线130电连接,并且第二沟道部分122通过布置在两个导电线130之间的导电结构140被电连接。第一垂直互连结构132可以具有如下横截面积:该横截面积的尺寸至少在一定程度上补偿由于第一沟道部分被布置在与第二沟道部分122不同的垂直水平处而引起的高度差所增加的电阻。

Claims (12)

1.一种用于形成垂直地堆叠在基板(100)上的第一晶体管和第二晶体管的互连结构的方法,其中所述第一晶体管包括水平延伸的第一沟道部分(112),且所述第二晶体管包括水平延伸的第二沟道部分(122),并且其中所述第一沟道部分被布置在所述第二沟道部分的上方,所述方法包括:
在所述基板中形成在所述第二沟道部分的旁边和下方延伸的导电线(130);
在所述导电线上形成用于电接触所述第一沟道部分的第一垂直互连结构(132);
从背面减薄所述基板以从下方露出所述导电线;
形成从下方露出所述第二沟道部分的通孔(146);
用导电材料填充所述通孔以形成第二垂直互连结构(142);以及
在所述第二垂直互连结构上形成导电结构(140)。
2.根据权利要求1所述的方法,其特征在于,还包括:
沉积覆盖所述导电线和所述第一和第二沟道部分的绝缘层(150);
在所述绝缘层中蚀刻出沟槽(152)以露出所述导电线以及第一和第二沟道部分;
在第一和第二沟道部分的侧壁处形成隔墙(154);以及
用导电材料填充所述沟槽,从而形成至少部分地从上方接触所述第一沟道部分的所述第一垂直互连结构。
3.根据权利要求1或2所述的方法,其特征在于,还包括:
在所述第一垂直互连结构上方形成结合层(160);
将载体晶片(162)结合到所述结合层;以及
翻转所述基板,以允许从所述基板的背面进行加工。
4.根据权利要求3所述的方法,其特征在于,还包括:
从所述背面形成与所述第二沟道部分对准的沟槽(144);
在所述沟槽的底部形成所述通孔(146);以及
沉积所述导电材料以填充所述通孔和所述沟槽,从而形成所述第二垂直互连和所述导电结构。
5.根据前述权利要求中的任一项所述的方法,其特征在于,所述导电线的露出部分和所述导电结构线的露出部分被布置在同一垂直水平上。
6.根据前述权利要求中的任一项所述的方法,其特征在于,还包括:
外延地形成包括交替的沟道材料层和牺牲材料层的堆叠结构(102);
将所述堆叠结构图案化成鳍;以及
从所述鳍的至少一部分移除牺牲材料层,其中所述沟道材料的剩余部分形成第一和第二沟道部分。
7.根据权利要求6所述的方法,其特征在于,所述沟道材料是由Si形成的,并且所述牺牲材料是由SiGe形成的。
8.根据权利要求6或7所述的方法,其特征在于,还包括形成至少部分地封闭所述第一和第二沟道部分的栅极结构(134)。
9.根据前述权利要求中的任一项所述的方法,其特征在于,所述基板包括蚀刻停止层(104),并且其中形成所述导电线包括向下蚀刻到所述蚀刻阻止层。
10.根据前述权利要求中的任一项所述的方法,其特征在于,包括在所述基板中在所述第二沟道部分的相对侧上形成第一和第二导电线,其中所述第一垂直互连结构被布置成将所述第二沟道部分与所述第一和第二导电线中的每一者互连。
11.一种半导体器件,包括:
垂直地堆叠在基板(100)上的第一晶体管和第二晶体管,其中所述第一晶体管包括水平延伸的第一沟道部分(112),且所述第二晶体管包括水平延伸的第二沟道部分(122),并且其中所述第一沟道部分被布置在所述第二沟道部分的上方;
布置在所述基板中并且在所述第二沟道部分的旁边和下方延伸的导电线(130);
布置在所述导电线上且用于接触所述第一沟道部分的第一垂直互连结构(132);
布置在所述第二沟道部分下方的导电结构(140);以及
在所述第二沟道部分和所述导电结构之间延伸的第二垂直互连结构(142)。
12.根据权利要求11所述的半导体器件,其特征在于,所述导电线和底部和所述导电结构的底部被布置在同一垂直水平处。
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