CN103000670B - 具有高沟道迁移率的SiC-MOSFET - Google Patents

具有高沟道迁移率的SiC-MOSFET Download PDF

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CN103000670B
CN103000670B CN201210345929.9A CN201210345929A CN103000670B CN 103000670 B CN103000670 B CN 103000670B CN 201210345929 A CN201210345929 A CN 201210345929A CN 103000670 B CN103000670 B CN 103000670B
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polysilicon layer
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CN103000670A (zh
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安东·毛德
罗兰·鲁普
汉斯-约阿希姆·舒尔茨
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Infineon Technologies AG
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Abstract

半导体装置(100)具有SiC(碳化硅)制成的半导体本体(101)以及场效应晶体管。场效应晶体管具有形成在SiC制成的半导体本体(101)内的漂移区(102)以及半导体本体(101)上的多晶硅层(103),其中,多晶硅层(103)具有10nm至50μm的范围内的平均粒度,并且包括源区(103s)以及体区(103b)。此外,场效应晶体管具有与体区(103b)邻接的栅结构(104)。

Description

具有高沟道迁移率的SiC-MOSFET
技术领域
本申请涉及一种半导体装置以及一种制造半导体装置的方法。
背景技术
碳化硅(SiC)是一种半导体材料,其具有许多用途所需的特性。所需的SiC的这些特性包括高的最大电子速度、高热导率以及高电击穿场强;高的最大电子速度实现高频率下的SiC元器件的运行,高热导率为SiC元器件简化多余热量的排放,而高电击穿场强为SiC元器件实现在高电压水平下的运行。
特别地,需要SiC场效应晶体管元器件,该SiC场效应晶体管元器件提供小的导通电阻,然而希望其中避免巨大的半导体器件并且基本上也不会对元器件的阻断能力产生不良影响。
发明内容
接下来,本发明的实施例涉及一种SiC半导体装置,该SiC半导体装置在反型沟道中具有提高了的迁移率,其中,尽管由此导致反型沟道中导通电阻或者说电阻的降低,元器件的阻断能力仍得以保持。其它实施例说明相应的用于半导体装置的制造方法。
本发明通过独立权利要求限定。本发明的改进方案在从属权利要求中。
一种实施方式涉及一种半导体装置,该半导体装置具有由碳化硅(SiC)制成的半导体本体以及场效应晶体管。场效应晶体管具有形成在半导体本体内的漂移区以及半导体本体上的多晶硅层,其中,多晶硅层具有10nm至5μm的范围内的平均粒度,并且包括源区以及体区。此外,场效应晶体管具有与体区邻接的栅结构。
用于制造根据本发明的实施方式所述的半导体装置的方法包括在由SiC制成的半导体本体上形成多晶硅层,其中,多晶硅层具有10nm至5μm的范围内的平均粒度。根据该方法,在多晶硅层内形成体区和源区,并且形成与体区邻接的栅结构。
附图说明
图1示出一种半导体装置的横截面图,该半导体装置具有场效应晶体管和由SiC制成的半导体本体,而场效应晶体管具有多晶硅层,在多晶硅层内有沟道在横向方向延伸。
图2A至2C示出根据图1的半导体装置的在相应区域的布置的替换实施方式的示意性俯视图。
图3A和3B示出场效应晶体管的示意性横截面图,该场效应晶体管具有多晶硅层,而多晶硅层具有垂直沟道和由SiC制成的半导体本体。
图4A至4C示出场效应晶体管装置的示意性横截面图,作为图1内所示出的实施方式的替换设计方案。
图5示意性示出具有用于制造半导体装置的方法的方法步骤的流程图。
具体实施方式
接下来,根据图示,进一步阐述实施例。然而,本发明并非仅限于具体说明的实施方式,而是能够以合适的方式进行修改和变换。一种实施方式的单个特征和特征组合能够恰当地与另一实施方式的特征和特征组合相结合,只要这种结合没有明确被排除。
在接下来根据图进一步阐述实施例之前,要注意:图中相同的元件用相同或者相似的参考标号标记,并且不会重复说明该元件。除此之外,不必忠实于比例地显示图,因为图的重点在于基本原理的图解和阐述。
接下来,定义pn结作为半导体本体内的位置,在该位置上,n型的掺杂剂浓度低于p型的掺杂剂浓度,或者p型的掺杂剂浓度低于n型的掺杂剂浓度,或者说p和n掺杂剂浓度之间的差别改变其符号。通过n-、n、n+、n++或者说p-、p、p+、p++精确说明掺杂剂浓度,其中,n-掺杂小于n掺杂,n掺杂小于n+掺杂,而n+掺杂小于n++掺杂。然而,统一用n标记的不同区域可以有不同的浓度值,但是,这些浓度值全部小于用n+或者n++标记的区域的数值,并且全部大于用n-标记的区域的数值。
图1示出半导体装置100的示意性横截面图,该半导体装置100具有场效应晶体管和由SiC制成的半导体本体101。场效应晶体管具有形成在由SiC制成的半导体本体101内的漂移区102和在半导体本体101的第一面109a(例如顶面)上的多晶硅层103。多晶硅层103具有10nm至5μm,特别是50nm至1μm的范围内的平均粒度。除此之外,多晶硅层103具有源区103s和体区103b。另外,场效应晶体管还具有与体区103b邻接的栅结构104。
如图1中所示,半导体本体101在SiC漂移区102旁具有SiC衬底105,以及SiC漂移区内的SiC屏蔽区106。与第一面109a相对的第二面109b(例如半导体本体101’的背面)上,布置有漏接触107,例如由金属和/或金属化合物制成的层或者层叠。横向方向例如与第一或者说第二面109a、109b平行地延伸,并且垂直方向与横向方向垂直。在根据图1的实施例中,SiC衬底105为n+掺杂,SiC漂移区102为n掺杂,体区103b为p掺杂,并且每个SiC屏蔽区106都是p掺杂。其中,源区103s是n+掺杂,并且在导通的情况下(im Leitungsfall),在体区103b中产生n型的反型沟道。显然,载流子类型也可以完全颠倒过来,以便场效应晶体管设计为p沟道场效应晶体管。换句话说,在此说明了用于n沟道增强型场效应晶体管的实施方式,然而,在相应的方式下,相似的也适用于p沟道增强型场效应晶体管。
在由SiC制成的半导体本体101上,布置有多晶硅层103。作为半导体装置100的场效应晶体管的栅结构104,在多晶硅层103上布置有介电层104d,介电层104d围绕栅极104g(例如多晶硅栅104g)。介电层104d能够包括多个部分,这些部分能够在不同的方法步骤中形成,并且也能够由不同的介电材料制成。介电层104d的一部分是形成在栅极104g和多晶硅层之间的栅介质。栅介质可以例如通过多晶硅层103的表面热氧化,通过氧化硅的CVD沉积或者通过这些方法的组合制得。然而,也可能由另一种材料制成介电层104d的栅介质,如作为高k介质,为栅极104g提供足够的绝缘特性。
在栅结构104(或者更精确地说,其介电层104d)与由SiC制成的半导体本体101的漂移区102之间,除了源区103s和体区103b以外,多晶硅层103还具有p+掺杂的体触点103k(Bodykontakt)以及n掺杂的导通区103a(Ableitgebiet)。导通区103a实现了电导通(Ableitung),例如从沟道到SiC漂移区102的低阻抗的电子导通。
SiC半导体本体101设计为例如单晶的,然而硅层103,还有可选地栅极104g由多晶硅制成。由于其多晶结构,与单晶硅层相比,多晶硅层103可以例如以更小的张力(Verspannung)涂覆到SiC衬底或者说由SiC制成的半导体本体101上。由于晶格失配,单晶硅层在SiC衬底上的外延沉积导致张力。特别地,相较于例如拉伸地在SiC上生长的单晶硅层,多晶硅层中的缺陷更平均地分布,以便能够减少在单元区域的单元(cell)中电特性的波动并且因此改善可靠性。
在多晶硅层103中,特别是在落在体区103b上的部分中,在半导体装置100的运行中,在接通状态下,形成反型沟道。通过已说明的10nm至5μm,特别是50nm至1μm的范围内的平均粒度,实现例如大于50cm2/Vs或者说甚至超过250cm2/Vs的半导体材料中的电子迁移率。常见的迁移率位于约50cm2/Vs至700cm2/Vs范围内,或者也可以位于250cm2/VS至700cm2/Vs范围内。不同于非晶硅结构,由于较大的晶粒结构以及与此相关的低相界数量,实现改善了的多晶硅的电子迁移率。可以通过继续粗化晶粒,相应地提高电子迁移率,这能够通过例如非晶硅的沉积和接下来的激光照射实现。其中,例如融化非晶层。在激光照射后,产生具有对应于加工或者说处理参数的粒度的多晶硅结构。此类多晶硅也被称作低温多晶硅(LTPS)。可能的LTPS的电子迁移率位于约100cm2/Vs至700cm2/Vs的范围内。
此外,也可以使用例如所谓的连续晶粒硅(CGS)作为多晶硅层,连续晶粒硅能够提供更高的电子迁移率。对于CGS,能够达到约600cm2/Vs或更高的电子迁移率,以便大概能够达到体硅(Bulk-Si)的数值,即便SiC作为衬底存在。
多晶硅层103只设置在例如反型沟道的范围内,而没有设置在场效应晶体管或者说半导体装置100的边缘终端区域(Randabschlussbereich)内。反型沟道位于所谓的单元区域(Zellenfeld)内,单元区域代表相应元器件的中心功能组成部分并且在该方面与相应的边缘终端区域相区分,而边缘终端区域用于例如在阻断运行中电场的横向衰减。从连接到多晶硅层103的单晶SiC结构101,102方向看去,多晶硅层103例如横向邻接源连接区域108(Source-Anschlussbereic)(例如源金属)。
对于作为MOSFET显示的该实施方式,典型的沟道区域的阻断能力只位于几伏特或者几十伏特的范围,然而尽管载流子迁移率相对于纯SiC半导体装置有所改善,该阻断能力还是不应减弱。由于p掺杂SiC屏蔽区106更深地伸入或者说掩埋的pn结屏蔽沟道区域,因此反向电压的主要部分由SiC半导体本体101承受。该屏蔽对应于例如混合肖特基二极管(Merged-Schottky-Diode)或者纯SiC MOSFET下的实现。
对于半导体装置,多晶硅层103的厚度d位于例如10nm至600nm或者30nm至250nm的范围内。导通区103a也能够理解为沟道区域103a,并且根据图1的实施方式,与连续的体区103b或者彼此隔开的单个体区相邻。
图1中两个被称为屏蔽区106的p掺杂区域能够设计为例如连续的屏蔽区106或者设计为彼此隔开的屏蔽区。其中,屏蔽区106具有与由SiC制成的半导体本体101的导电类型相反的导电类型。屏蔽区106的底面到多晶硅层底面的距离能够为电有源漂移区102(elektrisch aktiven Driftzone)的厚度的约5%至20%或者10%至20%。
屏蔽区106能够在其顶面电接触,并且电触点通过多晶硅层103中的开口接触屏蔽区106的顶面。在屏蔽区106的顶面终结的触点能够例如横向地接触源区103s和/或体触点103k。
此外,可能的还有:屏蔽区106在其顶面电接触,并且通过掺杂的体终端区域以及体触点103k建立电接触,其中,体触点103k还建立与体区103b的电接触。
围绕多晶硅栅极104g的介电层104d布置在多晶硅层103的沟道区域或者说导通区103上,并且根据不同的实施方式,形成栅介质的介电层104d的部分能够由例如氧化硅或者高k介质制成。
根据图1的实施方式所述,导通区103a具有对应于体区103b并且与源区103s相反的导电类型,其中,体区(Bodygebiet)103b有时形成在源区103s和导通区103a之间并且与二者邻接。如上文所提及的,可是,单个区域、范围或者说层也能够全部为分别相反的导电类型。
多晶硅层内的沟道区域的形成实现了具有高沟道迁移率的SiC场效应晶体管,由于在边缘终端区域中掏空(ausgesparten)的多晶层以及承受阻断电压的屏蔽区106,该SiC场效应晶体管没有阻断能力的损失。
图2A示出一种半导体装置200的实施方式的示意性俯视图,半导体装置200具有由SiC制成的包括场效应晶体管的半导体本体。与根据图1的实施方式相同,场效应晶体管具有形成在由SiC制成的半导体本体中的漂移区202以及半导体本体上的多晶硅层203,其中,多晶硅层203具有10nm至5μm的范围内的平均粒度和多个源区203s以及多个体区203b。在该实施例中,源区203s为n+掺杂,并且体区203b为p掺杂,其中,两个区域都由多晶硅制成,并且都形成在多晶硅层203中。
在多晶硅层203中,同样形成有多个由多晶硅制成的p+掺杂的体触点203k,体触点203k与源区203s一同交替地布置,并且与源区203s有相反的载流子类型。源区203s和体触点203k交替的方向例如垂直于图1中示出的布置的标号层面延伸。在图2a的左侧上,相关于接触沟槽220,分别有另一源区203s与一个源区203s相对设置。相应的,相关于接触沟槽220,还分别有另一体触点203k与一个体触点203k相对设置。这是示例性设计方案,并且在图2A的右侧显示对此的替换方式,在该替换方式中,相关于接触沟槽221,并没有另一源区与一个源区203s相对设置,而是体触点203k与一个源区203s相对设置。与此相应的,关于接触沟槽221,源区203s与每个体触点203k相对设置。多晶硅层同样能够在体区和导通区之间延伸(未在图2A中显示,参见图1)。在图2A中示出的布置是条形的单元设计。
半导体装置300的实施方式的另一示例性俯视图在图2B中示出。该图示出两个单元区域,这两个单元区域由连续的栅格状的接触沟槽320围绕。对于图2B左侧的单元,在中心示出n型的漂移区302,该n型的漂移区302被p掺杂的体区303b围绕。而体区303b自身又被源区303s以及体触点303k围绕,源区303s和体触点303k交替布置,并且形成体区303b的边缘。在该实施方式中,每个源区303s再次都是n+类型,而每个体触点303k都是p+类型。
根据图示2B左侧所示的源区303s和体触点303k的布置只是示范性的,并且因此在图2B的右侧,示出相应的源区303s或者说体触点303k的与此不同的布置,源区303s和体触点303k围绕体区域303b,而体区域303b自身又围绕漂移区302。特别地,图2B显示的两个单元示出:源区303s和体触点303k能够不同密度地依次布置。换句话说,能够设置不同数量的源区303s和体触点303k,以围绕相应的体触点303b。仅仅举例而言,源区303s的数量对应于体触点303k的数量。
在根据图2C中的示意性俯视图所示的半导体装置400的实施方式中,体区403b被接触区420围绕,其中,对体区403b而言,体区403b围绕多个依次布置的彼此相反掺杂的源区403s和体触点403k,而源区403s和体触点403k一同再次围绕另一接触区域421。
根据图2A、2B和2C所示的布置是示范性的,并且除了条形或者说矩形的单元几何形状,自然还可以有其它单元几何形状,例如六边形的、正方形的或者圆形的单元形状,对于这些单元形状,存在漂移区、体区以及源区和体触点的相应的形状。
图3A示出半导体装置500的另一实施方式,该半导体装置500具有场效应晶体管和由SiC制成的半导体本体501,其中,场效应晶体管具有形成在半导体本体501中的n掺杂的漂移区502和p掺杂的多晶硅层503,多晶硅层503代表体区503b,具有10nm至50μm范围内的平均粒度,并且包括n+掺杂的源区503s、p+掺杂的体触点503k以及n型导通区503a。此外,场效应晶体管具有与体区503b邻接并且设计在沟槽内的栅结构504。源区503s、导通区503a和体触点503k都以虚线显示在多晶硅层503内,因为它们通过多晶硅层形成或者说在其内通过掺杂形成。多晶硅层503的厚度位于例如0.5μm至3μm或者1μm至2μm的范围内。
如从图3A中所见,场效应晶体管设计为沟槽晶体管(Trench-Transistor),沟槽晶体管具有从多晶硅层503的表面伸入并终结在多晶硅层503中或者说其导通区503内的沟槽,其中,栅结构504与其栅极504g(例如多晶栅极)和围绕其的介电层504d一同形成在该沟槽内。在与沟道邻接的体区503b的部分中的沟道区域延伸在n+掺杂的源区503s和导通区503a之间。如图1所示,在该改进方案下,在SiC半导体本体501内也形成了由p掺杂的SiC制成的屏蔽区506,以保证场效应晶体管的阻断能力。
半导体装置600的对此替换的设计方案示出在图3B中,该半导体装置600具有设计为沟槽晶体管的场效应晶体管。该设计方案基本上对应于根据图3A所示的设计方案,然而,场效应晶体管具有从多晶硅层603的表面穿过多晶硅层603伸入到由SiC制成的半导体本体601中的沟槽。在该沟槽中,再次形成了具有介电层604d和栅极604g的栅结构604。与图3A相比,根据图3B的替换的沟槽相应地如此设计,即该沟槽完全穿过多晶硅层603。沟道区域因此终结在多晶硅层603到由SiC制成的半导体本体601的过渡区或者说结上。
图4A至4C示出所示出的(特别是根据图1的)半导体装置的其它替换700、800、900的示意性剖面图。因此,为相应的特征701、702、703、703s、703b、703k、704、704g、704d、705、706、707、708,或者说801、802、803、803s、803b、803k、804、804g、804d、805、806、807、808,或者说901、902、903、903s、903b、903k、904、904g、904d、905、906、907、908配备图1中特征101、102、103、103s、103b、103k、104、104g、104d、105、106、107、108的对应的参考标号,并且在此不再重复说明。
在图4A中,所显示的栅极704g设计为两部分,以便为了n+掺杂的源区703s的区域以及为了p+掺杂的体触点703k的区域,分别提供合适的栅极704g。此外,n掺杂的导通区703a没有设计为连续的。另外,除了栅极704g,在栅结构704的介电层704d中形成有具有正载流子的电荷岛777(Ladungsinseln),电荷岛777,例如通过涂覆Cs,形成在例如栅极704g的结构化之后。正载流子导致由多晶硅制成的n掺杂的导通区703a中的电子积聚,以及导致由SiC制成的半导体本体701中、在与具有电荷岛777的介电层704d的一部分的接触面上的电子积聚。通过电荷岛777引起的电子积聚改善了通过Si/SiC异质结的载流子流量。
在图4B中,与图4A相同,导通区803a没有设计为连续的。在每个导通区803a与半导体本体801的漂移区802之间,分别设计有简并区888(Entartungsgebiet),对于在此示例性配属的导电类型,简并区888具有n++掺杂。简并区888至少部分地形成在硅制的多晶层中,并且能够伸入由SiC制成的半导体本体801中。高度掺杂的简并区导致简并的Si/SiC异质结(Heterouebergang),并且因此改善通过异质结Si/SiC的载流子流。简并区通过例如离子注入和/或掺杂剂扩散产生。
在图4C中,同样以非连续的形式形成导通区903a。替代如图4B中的简并区888,形成金属区999。该金属区999能够设计为金属弯形物的形式,例如沉积并且结构化的金属喷涂的形式,并且在导通区903a和漂移区902之间建立电接触。举例而言,包括例如NiAl的金属区形成与由多晶硅制成的导通区903的欧姆接触,以及与由SiC制成的半导体本体901的欧姆接触。此外,可以在金属区999下铺设p掺杂的SiC屏蔽区906。这能够如此实现,即如此横向确定所显示的屏蔽区906的尺寸,即屏蔽区906也布置在金属区999下方。对此,可以改善例如半导体装置900或者说对应的场效应晶体管的阻断能力。金属区999能够理解为导通区903a和与导通区903a邻接的半导体本体901,特别是半导体本体901的漂移区902之间的金属短路。
图5示意性示出一种方法的方法步骤的流程,该方法用于制造根据上述实施方式所述的半导体装置。通过该方法,制造场效应晶体管,其中,进行下列步骤:在由SiC制成的半导体本体上形成多晶硅层,其中,多晶硅层具有10nm至5μm,特别是50nm至1μm的范围内的平均粒度(步骤S1);在多晶硅层内形成体区和源区(步骤S2);以及形成与体区邻接的栅结构(步骤S3)。
由SiC制成的半导体本体优选地由单晶SiC制成,其中,不同区域能够在原位(in-situ),即在相应的晶体生长期间,和/或例如通过离子注入和/或扩散已经进行掺杂。例如,体区能够在原位掺杂,并且源区、体触点区域和导通区通过离子注入进行掺杂。同样地,多晶硅层内的所有区域都能通过离子注入进行掺杂。如前文所述,硅层设计为多晶,并且具有10nm至5μm,特别是50nm至1μm的范围内的粒度。对此,能够首先沉积非晶硅,并且接下来用激光恰当地进行照射,以便产生相应的粒度。非晶层能够例如通过激光照射融化在SiC半导体本体上,并且再结晶,或者在分离的过程中,首先转化成晶粒结构,并且紧接着涂覆到SiC半导体本体上。通过激光照射,产生具有对应于加工参数的粒度的多晶硅结构。如此形成的多晶硅作为例如低温多晶硅(LTPS)而为人所知。可能的LTPS的电子迁移率位于约100至700cm2/Vs的范围内。
对于根据图5所示的方法的改进方案,场效应晶体管的边缘终端区域内的多晶硅层被移除。
在SiC半导体本体内,在例如形成多晶硅层之前,通过扩散和/或离子注入,形成掺杂的屏蔽区,以保证待生产的装置的阻断能力。与半导体本体相反地掺杂屏蔽区。

Claims (17)

1.半导体装置,包括:
SiC制成的半导体本体;
场效应晶体管,所述场效应晶体管具有:
形成在SiC制成的所述半导体本体内的漂移区(102);
在所述漂移区内的SiC屏蔽区(106);
所述半导体本体上的多晶硅层,其中,所述多晶硅层具有10nm至50μm的范围内的平均粒度并且包括源区(103s)以及体区(103b);以及
与所述体区(103b)邻接的栅结构,
其中,所述屏蔽区(106)通过电触点与所述源区电接触,
其中,所述多晶硅层的厚度d位于0.5μm至3μm的范围内,并且在所述体区中能够通过场效应控制的沟道在垂直方向上延伸
其中,所述场效应晶体管是沟槽晶体管,所述沟槽晶体管具有从所述多晶硅层的表面伸入至所述多晶硅层内并且终止在所述多晶硅层内的沟槽,所述沟槽具有形成在其内的栅结构。
2.根据权利要求1所述的半导体装置,其特征在于,所述体区(103b)中的载流子迁移率μ位于50cm2/(Vs)至700cm2/(Vs)的范围内。
3.根据权利要求1所述的半导体装置,其特征在于,所述多晶硅层形成在单元区域内,但是没有形成在所述场效应晶体管的边缘终端区域。
4.根据权利要求1至3中任一项所述的半导体装置,其特征在于在SiC制成的所述半导体本体内的屏蔽区(106),其中,所述屏蔽区具有与所述漂移区的导电类型相反的导电类型。
5.根据权利要求4所述的半导体装置,其特征在于,所述屏蔽区(106)的底面与所述多晶硅层的底面之间的距离为电有源漂移区(102)的厚度的5%至20%。
6.根据权利要求4所述的半导体装置,其特征在于,所述屏蔽区(106)在其顶面电接触,并且所述电触点通过所述多晶硅层中的开口接触所述屏蔽区(106)的顶面。
7.根据权利要求5所述的半导体装置,其特征在于,所述屏蔽区(106)在其顶面电接触,并且所述电触点通过所述多晶硅层中的开口接触所述屏蔽区(106)的顶面。
8.根据权利要求4所述的半导体装置,其特征在于,所述屏蔽区(106)在其顶面电接触,并且通过掺杂的体连接区域(103k)建立电接触,其中,所述体连接区域(103k)还形成与所述体区(103b)的电接触。
9.根据权利要求5所述的半导体装置,其特征在于,所述屏蔽区(106)在其顶面电接触,并且通过掺杂的体连接区域(103k)建立电接触,其中,所述体连接区域(103k)还形成与所述体区(103b)的电接触。
10.根据权利要求1至3中任一项所述的半导体装置,其特征在于形成在所述体区(103b)上的栅介质,所述栅介质由氧化硅和高k介质组成的组中的材料构成。
11.根据权利要求1至3中任一项所述的半导体装置,其特征在于所述多晶硅层内的导通区,其中,所述导通区具有与所述源区(103s)一致的并且与所述体区(103b)相反的导电类型,并且所述体区(103b)形成在所述源区(103s)和所述导通区之间并且与二者邻接。
12.根据权利要求11所述的半导体装置,其特征在于所述导通区和与所述导通区邻接的SiC制成的所述半导体本体之间的金属短路(999)。
13.根据权利要求11所述的半导体装置,其特征在于电荷积聚区(777),所述电荷积聚区(777)介电地与位于所述导通区和与所述导通区邻接的SiC制成的所述半导体本体之间的结隔开,并且适合于通过场效应诱发所述导通区和与所述导通区邻接的SiC制成的所述半导体本体之间的结上的载流子积聚。
14.根据权利要求11所述的半导体装置,其特征在于,所述导通区与所述半导体本体之间的边界区域中的所述导通区和/或SiC制成的所述半导体本体被掺杂直至简并。
15.根据权利要求1至3中任一项所述的半导体装置,其中,所述场效应晶体管是在所述源区(103s)与漏区(107)之间具有垂直通过电流的n沟道场效应晶体管,所述n沟道场效应晶体管在所述半导体本体的第一表面(109a)上具有所述源区(103s),并且在SiC制成的所述半导体本体的与所述第一表面(109a)相对的第二表面(109b)上具有所述漏区(107)。
16.一种用于制造半导体装置的方法,包括:
制造场效应晶体管,包括:
在SiC制成的半导体本体上形成多晶硅层,其中,所述多晶硅层具有10nm至50μm的范围内的平均粒度,所述半导体本体具有漂移区(102);
在所述漂移区(102)内形成SiC屏蔽区(106);
在所述多晶硅层内,形成体区(103b)和源区(103s),并且
形成与所述体区(103b)邻接的栅结构,
其中,所述屏蔽区(106)通过电触点与所述源区电接触,
其中,所述多晶硅层的厚度d位于0.5μm至3μm的范围内,并且在所述体区中能够通过场效应控制的沟道在垂直方向上延伸,
其中,所述场效应晶体管是沟槽晶体管,所述沟槽晶体管具有从所述多晶硅层的表面伸入至所述多晶硅层内并且终止在所述多晶硅层内的沟槽,所述沟槽具有形成在其内的栅结构。
17.根据权利要求16所述的方法,其特征在于
移除所述场效应晶体管的边缘终端区域内的所述多晶硅层。
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