CN110771027B - 功率半导体装置及使用该装置的电力转换装置 - Google Patents

功率半导体装置及使用该装置的电力转换装置 Download PDF

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CN110771027B
CN110771027B CN201880039030.XA CN201880039030A CN110771027B CN 110771027 B CN110771027 B CN 110771027B CN 201880039030 A CN201880039030 A CN 201880039030A CN 110771027 B CN110771027 B CN 110771027B
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power semiconductor
insulating member
semiconductor device
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CN110771027A (zh
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露野円丈
岛津博美
难波明博
松下晃
宝藏寺裕之
西原淳夫
石井利昭
平尾高志
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Hitachi Astemo Ltd
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Abstract

本发明的目的在于确保功率半导体装置的可靠性并且提高生产率。本发明的特征在于，具备：电路体，其包含半导体元件和导体部而构成；第1绝缘构件和第2绝缘构件，它们隔着所述电路体相互对置；第1基座和第2基座，它们隔着所述电路体、所述第1绝缘构件和所述第2绝缘构件相互对置；壳体，其形成有由所述第1基座覆盖的第1开口部以及由所述第2基座覆盖的第2开口部；以及距离限制部，其设置在所述第1基座和所述第2基座之间的空间内，并且通过与该双方的基座接触来限制该第1基座和该第2基座之间的距离。

Description

功率半导体装置及使用该装置的电力转换装置
技术领域
本发明涉及一种搭载有功率半导体元件的功率半导体装置以及具有该功率半导体装置的电力转换装置。
背景技术
通过功率半导体元件的开关来转换电力的装置由于转换效率高，因此被广泛用于民用、车载用、铁道用、变电设备等。该功率半导体元件通过通电而发热，因此要求高散热性。特别是在车载用途中，为了小型化和轻量化，采用使用了液体的制冷剂的高效率的冷却系统。例如，关于在电力转换装置中使用的、将树脂模制后的半导体装置收纳在壳体中的功率模块，公开了专利文献1。
现有技术文献
专利文献
专利文献1：日本专利特开2011-233606号公报
发明内容
发明要解决的问题
专利文献1所记载的功率模块在具有包围散热板的薄壁部的壳体中收纳有密封了半导体元件的密封体，因此在将密封体与壳体压接后，需要通过浇注树脂对密封体和壳体之间进行密封的工序。
本发明的课题在于，在不降低功率半导体装置的可靠性的情况下，提高生产率。
用于解决问题的技术手段
本发明的特征在于，具备：电路体，其包含半导体元件和导体部而构成；第1绝缘构件和第2绝缘构件，它们隔着所述电路体相互对置；第1基座和第2基座，它们隔着所述电路体、所述第1绝缘构件和所述第2绝缘构件相互对置；壳体，其形成有由所述第1基座覆盖的第1开口部和由所述第2基座覆盖的第2开口部；以及距离限制部，其设置在所述第1基座和所述第2基座之间的空间内，并且通过与该双方的基座接触来限制该第1基座和该第2基座之间的距离。
发明的效果
根据本发明，能够在不降低功率半导体装置的可靠性的情况下提高生产率。
附图说明
图1是本实施方式的功率半导体装置300的整体立体图。
图2是构成功率半导体装置300的集电极侧基板810的立体图。
图3是构成功率半导体装置300的发射极侧基板820的立体图。
图4是本实施方式的壳体805的立体图。
图5(a)是从图4的平面A的箭头方向观察到的壳体805的截面图。
图5(b)是表示将集电极侧基板810从下侧搭载在壳体805上的状态的截面图。
图5(c)是表示将电路部件的一部分搭载在集电极侧基板810上的状态的截面图。
图5(d)是表示将发射极侧基板820从下侧搭载在壳体805上的状态的截面图。
图6(a)是表示第2基座821的加工工序的截面图。
图6(b)是表示图6(a)的加工部分的放大截面图。
图6(c)是表示激光焊接的工序的截面图。
图6(d)是表示通过传递模塑进行树脂密封的工序的截面图。
图7是与图5(c)工序对应的功率半导体装置300的制造工序过程中的立体图。
图8是与图6(c)工序对应的功率半导体装置300的制造工序过程中的立体图。
图9(a)是其他实施方式的功率半导体装置的截面图。
图9(b)是其他实施方式的功率半导体装置的截面图。
图9(c)是其他实施方式的功率半导体装置的截面图。
图10是图1至图9所示的任一功率半导体装置的电路图。
图11是搭载了本实施方式的功率半导体装置300的电力转换装置200的截面立体图。
具体实施方式
以下，作为本发明的结构体的实施方式，对车辆搭载用的电力转换装置所使用的功率半导体装置进行说明。在以下说明的功率半导体装置的实施方式中，参照附图对作为发热体的功率半导体元件、搭载功率半导体元件的导体部、具有与该发热体热连接的作为散热板的散热片部的基座、以及作为固定该发热体和该散热板的树脂材料的密封树脂等各构成要素进行说明。此外，在各图中，对于相同的要素标注相同的符号，并省略重复的说明。
图1是本实施方式的功率半导体装置300的整体立体图。功率半导体装置300具备：金属制的壳体805、具有散热片的金属制的基座860、收纳于壳体805中的密封树脂850、直流端子315B及直流端子319B、交流端子320B、信号端子325U、信号端子325L及信号端子325S。
信号端子325U向构成逆变电路的上臂的功率半导体元件传递信号。信号端子325L向构成逆变器电路的下臂的功率半导体元件传递信号。信号端子325S构成电流检测用的端子和温度检测用的端子。
壳体805形成密封部800和密封部801，该密封部800形成在交流端子320B等贯通的开口附近，该密封部801形成在直流端子315B及直流端子319B贯通的开口附近。焊接部809设置在壳体805和基座860的边界部。
在壳体805中，冷却水与由密封部800与密封部801夹着的区域接触。冷却水通过壳体805、基座860和焊接部809这样的金属制材料与密封树脂850隔离。
由此，能够防止由冷却水引起的密封树脂850的吸湿，确保高可靠性。信号端子325L、信号端子325U、信号端子325S以及交流端子320B从功率半导体装置300的一面突出成一列。由于它们与控制电路、驱动电路、电流传感器连接，因此通过从一面突出，而具有能够简化逆变器布局的效果。
另外，直流端子315B和直流端子319B从功率半导体装置300的一面突出成一列。通过使直流端子315B与直流端子319B相邻，具有使输入输出的电流接近而降低电感的效果。另外，由于直流端子315B和直流端子319B与连结在电池上的电容器模块连接，因此通过从一个面突出，而具有能够简化逆变器布局的效果。
图2是构成功率半导体装置300的集电极侧基板810的立体图。
导体部813具有搭载功率半导体元件的元件搭载部和搭载直流端子315B等的端子搭载部。第1基座811是形成散热片的金属制构件。第1绝缘构件812形成在导体部813和第1基座811之间，使导体部813和第1基座811绝缘。另外，在第1绝缘构件812上设置有后述的距离限制部807、807a。
第1基座811只要是金属材料就没有特别限制，但从散热性这一点考虑，优选铜或铝，进一步考虑与图1所示的壳体805的焊接性，则最优选铝。
由于第1基座811的散热片与冷却水接触，因此从防腐蚀性这一点出发，最表面优选处理成铝、防蚀铝或镍等。
导体部813只要是具有导电性的材料就没有特别限制，但优选导电性优异的铜或铝。为了提高钎焊连接性，导体部813的一部分或整体优选实施包含镀镍的电镀。另外，为了提高导体部813与密封树脂850的密合性，优选实施粗化等加工。
导体部813a通过未图示的Al线与功率半导体元件的栅极电极连接。导体部813b与图1所示的信号端子325U连接。通过连结这些导体部813a和导体部813b，使集电极侧基板810小型化。
在该情况下，当用于连接导体部813b和信号端子325U的接合构件流出到导体部813a时，Al线的连接变得困难。因此，导体部813a的宽度形成得比导体部813b的宽度小。由此，抑制连接信号端子325U的接合材料流出到连接Al线的导体部813a。
另外，导体部813c和导体部813d与导体部813b连接。即,从导体部813b分支出多个导体部813c和导体部813d。特别是导体部813c和导体部813d在相互远离的方向上形成。
由此，防止在以2个并联的方式搭载功率半导体元件的情况下的Al线的立体交叉，防止传递模塑时的引线变形引起的短路。
第1绝缘构件812只要是绝缘性材料就没有特别限制，但从耐热性及热传导性的观点出发，优选陶瓷。在第1绝缘构件812为陶瓷的情况下，为了提高与密封树脂850的密合性，优选利用激光等进行表面粗化、形成有机薄膜等。
第1基座811及导体部813通过钎料与第1绝缘构件812连接，或者通过图案形成等与第1绝缘构件812连接。更具体而言，第1基座811及导体部813也可以由铝熔液形成在第1绝缘构件812的两面。在功率半导体装置300的组装前，通过预先粘接第1基座811及导体部813与第1绝缘构件812，能够在功率半导体装置300的组装工序中省略粘接工序，能够降低制造成本。
图3是构成功率半导体装置300的发射极侧基板820的立体图。
导体部823搭载功率半导体元件。在本实施方式中，导体部823a搭载构成逆变电路的上臂的两个IGBT和两个二极管。导体部823b搭载构成逆变电路的下臂的两个IGBT和两个二极管。
第2基座821具有散热片，并且由金属制构件构成。第2绝缘构件822形成在导体部823和第2基座821之间，使导体部823和第2基座821绝缘。
另外，在第2绝缘构件822上设置有后述的距离限制部807d至807f。
导体部823具有用于与功率半导体元件的发射极侧连接的第1突起部823c、用于与集电极侧基板810的布线连接的第2突起部823d。由此，具有如下的效果：使集电极侧基板810和发射极侧基板820的电连接部的接合构件的厚度均等，抑制连接时的倾斜，容易确保平行度。
图4是本实施方式的壳体805的立体图。壳体805形成用于供集电极侧基板810、发射极侧基板820插入的贯通孔805a、用于供直流端子315B等插入的贯通孔805b、用于供交流端子320B等插入的贯通孔805c。
壳体805只要是具有防水性的金属材料就没有特别限制，但考虑到加工性以及与基座的焊接性，最优选铝。
使用图5至图8说明本实施例的功率半导体装置300的制造工序。
图5(a)是从图4的平面A的箭头方向观察到的壳体805的截面图。
图5(b)是表示将集电极侧基板810从下侧搭载在壳体805上的状态的截面图。
图5(c)是表示将电路部件的一部分搭载在集电极侧基板810上的状态的截面图。
连接构件841设置在集电极侧基板810的导体部813上。进而，功率半导体元件804及交流端子320B等端子经由连接构件841而与导体部813连接。然后,将未图示的Al线与导体部813和功率半导体元件804连接。
图5(d)是表示将发射极侧基板820从下侧搭载在壳体805上的状态的截面图。此时，距离限制部807a和距离限制部807e的各自的顶面抵接。由此，能够使第1基座811和第2基座821的高度为不干扰壳体805的高度，能够防止第1基座811、第2基座821与壳体805的干扰。
并且，通过防止在利用连接构件841进行连接时与壳体805的干扰，能够提高电连接部的品质。另外，通过精密地规定第1基座811和第2基座821的高度，能够确保焊接第1基座811、第2基座821与壳体805所需的尺寸。
图6(a)是表示第2基座821的加工工序的截面图。图6(b)是表示图6(a)的加工部分的放大截面图。
第2基座821为不干扰壳体805的高度。因此，通过在第2基座821上设置弯折部806，使第2基座821的周缘接近壳体805。
此外，第1基座811和壳体805由于壳体805的自重而通过第1基座811相互接触。
图6(c)是表示激光焊接的工序的截面图。通过激光焊接连接第1基座811和壳体805、进而连接第2基座821和壳体805，分别形成焊接部809。
图6(d)是表示通过传递模塑进行树脂密封的工序的截面图。在壳体805与第1基座811及第2基座821的间隙中，通过传递模塑来密封密封树脂850。
由于壳体805与第1基座811、以及壳体805与第2基座821被焊接，因此密封树脂850不会向散热片侧流出。另外，通过用密封树脂850覆盖壳体805的端面805d及805e，能够使交流端子320B等端子与壳体805绝缘。然后，切割未图示的引线框的连接杆，形成端子，从而得到功率半导体装置300。
图7是与图5(c)工序对应的功率半导体装置300的制造工序过程中的立体图。
在集电极侧基板810上以2个并联的方式焊接有作为功率半导体元件的上臂侧的IGBT155A及155B、上臂侧的二极管156A及156B、下臂侧的IGBT157A及157B、下臂侧的二极管158A及158B。这里，IGBT是绝缘栅双极晶体管(Insulated Gate Bipolar Transistor)的缩写。IGBT155A等分别通过Al线840从栅极及温度读出与集电极侧基板810的导体部813b等连接。连接杆830至832将交流端子320B等端子彼此连接。
图8是与图6(c)工序对应的功率半导体装置300的制造工序过程中的立体图。
焊接部809设置在第2基座821与壳体805相接的边界部。通过焊接壳体805与第1基座811及第2基座821，能够防止由冷却水引起的密封树脂的吸湿，确保高可靠性。
图9(a)是其他实施方式的功率半导体装置的截面图。第1基座811和第2基座821的距离能够通过距离限制部207保持固定。
本实施方式的距离限制部207由第1绝缘构件812、从壳体805的一部分延伸的隔板805d、形成于第2绝缘构件822上的导体部823e、以及第2绝缘构件822构成。导体部823e以比其他导体部823a等更接近第1绝缘构件812的方式突出。
图9(b)是其他实施方式的功率半导体装置的截面图。第1基座811和第2基座821的距离能够通过距离限制部307保持固定。
本实施方式的距离限制部307由第1绝缘构件812、形成于第1绝缘构件812上的导体部814f、直流端子315B、形成于第2绝缘构件822上的导体部823f、以及第2绝缘构件822构成。此外，也可以是直流端子315B以外的直流端子319B、交流端子320B等端子。在本实施方式中，端子作为距离限制部307的一部分发挥作用，能够抑制部件数量的增加、装置的大型化。
图9(c)是其他实施方式的功率半导体装置的截面图。第1基座811和第2基座821的距离能够通过距离限制部407保持固定。
距离限制部407由从第1基座811突出的第1突出部811a和从第2基座821突出的第2突出部821a构成。第1突出部811a也可以与第1基座811一体地构成。第2突出部821a也可以与第2基座821一体地构成。通过减少构成距离限制部407的构件，能够减小尺寸公差，或者提高对于破裂等破坏的可靠性。
图10是图1至图9所示的任一功率半导体装置的电路图。
直流端子315B从上臂电路的集电极侧输出，与电池或电容器的正极侧连接。信号端子325U从上臂电路的IGBT155的栅极及发射极读出输出。
直流端子319B从下臂电路的发射极侧输出，与电池或电容器的负极侧或GND连接。信号端子325L从下臂电路的IGBT157的栅极和发射极读出输出。交流端子320B从下臂电路的集电极侧输出，与马达连接。在进行中性点接地的情况下，下臂电路不与GND连接，而与电容器的负极侧连接。
本实施方式的功率半导体装置是将上臂电路及下臂电路这两个臂电路一体化为一个模块的结构即2in1结构。除了2in1结构以外，在使用3in1结构、4in1结构、6in1结构等的情况下，能够减少来自功率半导体装置的输出端子的数量，实现小型化。
图11是搭载了本实施方式的功率半导体装置300的电力转换装置200的截面立体图。
本实施方式的电力转换装置200的外观由上表面或底面为大致长方形的框体12、设置在框体12的短边侧的外周的一个上的上部壳体10、用于堵塞框体12的下部开口的下部壳体16构成。
通过将功率半导体装置300设置在由壳体12及流路形成体100构成的结构体上而形成流路。在插入功率半导体装置300后，组装层叠电极引线框700，焊接交流电极端子320B与层叠电极引线框。
接着，组装搭载有安装部件的控制电路172、驱动电路174，与信号端子325U等连接。位于功率半导体装置300的下部的直流端子与电容器模块500焊接。然后，搭载下部壳体16、上部壳体10。通过将功率半导体装置300接近排列，在上部设置控制电路，在下部设置电容器模块，能够紧凑地配置并实现小型化。在功率半导体装置300的密封部800、801上设置有O形环等弹性体。
符号说明
10…上部壳体、12…壳体、16…下部壳体、155A…IGBT、155B…IGBT、156A…二极管、156B…二极管、157A…IGBT、157B…IGBT、158A…二极管、158B…二极管、200…电力转换装置、207…距离限制部、300…功率半导体装置、307…距离限制部、315B…直流端子、319B…直流端子、320B…交流端子、325L…信号端子、325U…信号端子、325S…信号端子、800…密封部、801…密封部、804…功率半导体元件、805…壳体、805a～805c…贯通孔、805d…隔板、806…弯折部、807a～807f…距离限制部、809…焊接部、810…集电极侧基板、811第1基座、811a…第1突出部、812…第1绝缘构件、813…导体部、813a…导体部、813b…导体部、813c…导体部、813d…导体部、813e…导体部、813f…导体部、820…发射极侧基板、821…第2基座、821a…第2突出部、822…第2绝缘构件、823…导体部、823a…导体部、823b…导体部、823c…第1突起部、823d…第2突起部、823e…导体部、823f…导体部、830…连接杆、831…连接杆、832…连接杆、840…Al线、841…连接构件、850…密封树脂、860…基座。

Claims (7)

1.一种功率半导体装置，其特征在于，具备：
电路体，其包含半导体元件和导体部而构成；
第1绝缘构件和第2绝缘构件，它们隔着所述电路体相互对置；
第1基座和第2基座，它们隔着所述电路体、所述第1绝缘构件和所述第2绝缘构件相互对置；
壳体，其形成有由所述第1基座覆盖的第1开口部和由所述第2基座覆盖的第2开口部；以及
距离限制部，其设置在所述第1基座和所述第2基座之间的空间内，并且通过隔着所述第1绝缘构件或所述第2绝缘构件与该双方的基座接触来限制该第1基座和该第2基座之间的距离。
2.根据权利要求1所述的功率半导体装置，其特征在于，
所述第1绝缘构件和所述第2绝缘构件是陶瓷基板，
所述距离限制部从所述陶瓷基板突出。
3.根据权利要求1所述的功率半导体装置，其特征在于，
所述第1基座或所述第2基座具有朝向配置有所述壳体的一侧变形的弯折部，并且所述弯折部与该壳体连接。
4.根据权利要求1或2所述的功率半导体装置，其特征在于，
所述第1基座或所述第2基座在该第1基座或该第2基座与所述壳体之间的空间内填埋树脂密封材料。
5.一种功率半导体装置，其特征在于，具备：
电路体，其包含半导体元件和导体部而构成；
第1绝缘构件和第2绝缘构件，它们隔着所述电路体相互对置；
第1基座和第2基座，它们隔着所述电路体、所述第1绝缘构件和所述第2绝缘构件相互对置；
壳体，其形成有由所述第1基座覆盖的第1开口部和由所述第2基座覆盖的第2开口部；以及
距离限制部，其设置在所述第1基座和所述第2基座之间的空间内，并且通过与该双方的基座接触来限制该第1基座和该第2基座之间的距离
所述距离限制部由第1突出部和第2突出部构成，所述第1突出部形成于所述第1基座上且朝向所述第2基座突出，所述第2突出部形成于所述第2基座上且朝向所述第1基座突出，
所述第1突出部通过与所述第2突出部接触来限制所述第1基座和所述第2基座之间的距离。
6.根据权利要求5所述的功率半导体装置，其特征在于，
所述第1基座或所述第2基座具有朝向配置有所述壳体的一侧变形的弯折部，并且所述弯折部与该壳体连接。
7.根据权利要求5所述的功率半导体装置，其特征在于，
所述第1基座或所述第2基座在该第1基座或该第2基座与所述壳体之间的空间内填埋树脂密封材料。
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