CN109686716A - 晶圆级扇出封装的圆片结构及采用该圆片结构的晶圆级扇出封装工艺 - Google Patents
晶圆级扇出封装的圆片结构及采用该圆片结构的晶圆级扇出封装工艺 Download PDFInfo
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Abstract
本发明涉及一种晶圆级扇出封装的圆片结构及采用该圆片结构的晶圆级扇出封装工艺,属于晶圆级封装技术领域。所述晶圆级扇出封装的圆片结构,包括金属框架单元、芯片和塑封料,所述金属框架单元包括主框架和连脚,连脚设置于主框架的四周;所述主框架采用封闭的框架结构,主框架包围芯片。所述的晶圆级扇出封装工艺,包括以下步骤:(1)基板上贴装临时键合膜;(2)在临时键合膜上贴装金属框架结构;(3)贴装芯片;(4)将金属框架结构和芯片注塑在一起,得到圆片结构;(5)去除基板及临时键合膜;(6)晶圆级再布线;(7)植球;(8)划片。本发明的金属框架结构在注塑过程能够更好的抵抗塑封料流淌引起的芯片偏移问题。
Description
技术领域
本发明涉及一种晶圆级扇出封装的圆片结构及采用该圆片结构的晶圆级扇出封装工艺,属于晶圆级封装技术领域。
背景技术
随着微电子制造技术的迅速发展,电子产品向更薄、更小、更轻方面发展,采用单颗芯片封装技术已经逐渐无法满足产业需求,晶圆级封装(WLP)技术以BGA技术为基础,所有的封装与测试过程都以圆片为单位进行,使得封装尺寸小至芯片尺寸,生产成本大幅度降低。这使得晶圆级封装技术获得巨大发展和广泛应用。
晶圆级扇出封装采用再构圆片的方式将芯片I/O端口引出,在重构的包封体上形成焊球或凸点终端阵列,在一定范围内可代替传统的引线键合焊球阵列封装或倒装芯片焊球阵列封装结构,特别适用于便携式消费电子应用领域。
在晶圆级扇出封装中,由于芯片材料与塑封料之间的热膨胀系数差异,引起塑封后的圆片翘曲较大,同时由于注塑过程中的塑封料的流动导致芯片位置出现不规律的偏移,这些都会造成再布线工艺实施困难影响产量和良率。传统解决方法以减少芯片阵列数量,增加芯片间间距以达到减小翘曲、便于划片的效果,效率低、加工工时长、成本高。
发明内容
本发明的目的是克服现有技术中存在满整列圆片塑封后翘曲过大、以及注塑过程中普遍存在的芯片偏移问题,提供一种晶圆级扇出封装的圆片结构及采用该圆片结构的晶圆级扇出封装工艺,满足高可靠塑封的封装要求。
按照本发明提供的技术方案,所述晶圆级扇出封装的圆片结构,其特征是:包括金属框架单元、芯片和塑封料,所述金属框架单元和芯片塑封于塑封料中;所述金属框架单元包括主框架和连脚,连脚设置于主框架的四周;所述主框架采用封闭的框架结构,主框架包围芯片。
进一步地,所述主框架每侧边设置2-3个连脚。
进一步地,所述主框架的内部尺寸大于芯片的尺寸。
进一步地,所述金属框架单元的厚度小于芯片的厚度。
进一步地,所述主框架采用封闭的多边形框架结构或圆形框架结构。
进一步地,所述主框架采用矩形框架结构。
进一步地,所述金属框架单元采用的金属材料热膨胀系数高于塑封料的热膨胀系数。
采用上述圆片结构的晶圆级扇出封装工艺,其特征是,包括以下步骤:
(1)基板上贴装临时键合膜;
(2)在临时键合膜上贴装金属框架结构;所述金属框架结构由若干个阵列排布的金属框架单元构成,相邻金属框架单元由连脚连接;所述金属框架单元的阵列方式与待排布的芯片排布方式保持一致;
(3)贴装芯片,芯片的安装位置位于金属框架结构的内部,由金属框架结构将芯片包围;装片过程中,每一块芯片的装片都以该芯片所在的金属框架单元中心进行装片定位;
(4)晶圆级注塑重构,将金属框架结构和芯片注塑在一起,得到圆片结构;
(5)去除基板及临时键合膜;
(6)晶圆级再布线;
(7)植球;
(8)划片,得到晶圆级封装。
进一步地,所述步骤(2)中,金属框架结构直接通过机械加工的方式获得,或者通过刻蚀方法获得。
本发明与已有技术相比具有以下优点:
(1)本发明将金属框架单元与芯片一起进行塑封,与现有技术中直接将芯片贴合在临时键合膜上塑封相比,本发明的金属框架结构在注塑过程能够更好的抵抗塑封料流淌引起的芯片偏移问题;
(2)本发明中金属框架采用热膨胀系数高于塑封料的金属材料,与现有的塑封方案相比,本发明的金属框架结构能够抑制塑封后圆片的翘曲问题。
附图说明
图1为本发明所述晶圆级扇出封装的圆片结构的剖视图。
图2为本发明所述晶圆级扇出封装的圆片结构的俯视图。
图3为基板上安装金属框架结构和芯片后的示意图。
图4为图3的剖视图。
附图标记说明: 1-金属框架单元、2-芯片、3-塑封料、4-主框架、5-连脚、6-金属框架结构。
具体实施方式
下面结合具体附图对本发明作进一步说明。
如图1、图2所示,本发明所述晶圆级扇出封装的圆片结构包括金属框架单元1、芯片2和塑封料3,所述金属框架单元1和芯片2塑封于塑封料3中;所述金属框架单元1包括主框架4和连脚5,连脚5设置于主框架4的四周;所述主框架4采用封闭的框架结构,主框架4的内腔尺寸大于芯片2的尺寸,主框架4包围芯片2;在本实施例中,如图2所示,所述主框架4采用回字形结构,但不仅仅局限于回字形。
如图2所示,所述连脚5设置于主框架4的外侧四周,对于芯片尺寸较小时,四周的连脚5可以较少,主框架4每侧边设置2个连脚5;对于芯片尺寸较大时,主框架4每侧边设置3个连脚5,并适当增加每个连脚5的宽度。具体地,所述主框架4的内孔尺寸参数根据芯片2的尺寸决定,主框架4的外部尺寸根据芯片2排布方式及最终封装尺寸综合决定,在一个具体实施方式中,采用3.3mm×2.7mm×0.36mm的芯片,采用的金属框架单元1厚度为0.05mm,主框架4的框架宽度为0.03mm,主框架4的框架外边长为4.5mm,连脚5的宽度为0.03mm,封装后的封装结构的尺寸为6mm×6mm×0.63mm。
在具体应用中,所述金属框架单元1的厚度小于芯片2的厚度,根据不同的芯片尺寸与排布方式,尺寸较大的金属框架单元1可直接通过机械加工的方式获得,对于较小尺寸的金属框架单元1,可通过刻蚀等方法获得。
本发明所述的晶圆级封装用金属框架采用的金属材料热膨胀系数高于塑封料的热膨胀系数。
采用本发明所述圆片结构的晶圆级扇出封装工艺,具体包括以下步骤:
(1)基板上贴装临时键合膜;
(2)如图3所示,在临时键合膜上均匀贴装金属框架结构6,可采用机械夹具、气动夹具等方式对金属框架结构6进行定位后安装;所述金属框架结构6由若干个阵列排布的金属框架单元1构成,相邻金属框架单元1由连脚5连接,其阵列方式与芯片2的排布方式保持一致;
所述金属框架结构6可以根据芯片尺寸大小进行另工,尺寸较大的金属框架结构6直接通过机械加工的方式获得,尺寸较小的金属框架结构6可以通过刻蚀等方法获得;
(3)贴装芯片;采用机械夹具、气动夹具等方式完成芯片的安装,芯片的安装位置基于金属框架的相对位置进行安装,能够提高芯片的安装精度;装片过程中,每一块芯片的装片都以该芯片所在的金属框架单元中心进行装片定位;如图4所示,为完成步骤(2)和步骤(3)后,基板上金属框架结构与芯片的布局图,金属框架结构的金属框架单元的安装排列方式及个数与芯片2的安装排列方式及个数保持一致;
(4)晶圆级注塑重构,即实现金属框架的埋置,得到本发明所述的圆片结构;
(5)去除基板及临时键合膜;
(6)晶圆级再布线;
(7)植球;
(8)划片,得到具有本发明所述圆片结构的晶圆级封装;划片过程中,针对不同的塑封圆片中金属框架单元的尺寸,应选择合适的刀具和划片速度等工艺参数。
尽管已描述了本发明的优选实施例,但本领域内的技术人员一旦得知了基本创造性概念,则可对这些实施例作出另外的变更和修改。所以,所附权利要求意欲解释为包括优选实施例以及落入本发明范围的所有变更和修改。
显然,本领域的技术人员可以对本发明进行各种改动和变型而不脱离本发明的精神和范围。这样,倘若本发明的这些修改和变型属于本发明权利要求及其等同技术的范围之内,则本发明也意图包含这些改动和变型在内。
Claims (9)
1.一种晶圆级扇出封装的圆片结构,其特征是:包括金属框架单元(1)、芯片(2)和塑封料(3),所述金属框架单元(1)和芯片(2)塑封于塑封料(3)中;所述金属框架单元(1)包括主框架(4)和连脚(5),连脚(5)设置于主框架(4)的四周;所述主框架(4)采用封闭的框架结构,主框架(4)包围芯片(2)。
2.如权利要求1所述的晶圆级扇出封装的圆片结构,其特征是:所述主框架(4)每侧边设置2-3个连脚(5)。
3.如权利要求1所述的晶圆级扇出封装的圆片结构,其特征是:所述主框架(4)的内部尺寸大于芯片(2)的尺寸。
4.如权利要求1所述的晶圆级扇出封装的圆片结构,其特征是:所述金属框架单元(1)的厚度小于芯片(2)的厚度。
5.如权利要求1所述的晶圆级扇出封装的圆片结构,其特征是:所述主框架(4)采用封闭的多边形框架结构或圆形框架结构。
6.如权利要求5所述的晶圆级扇出封装的圆片结构,其特征是:所述主框架(4)采用矩形框架结构。
7.如权利要求1所述的晶圆级扇出封装的圆片结构,其特征是:所述金属框架单元采用的金属材料热膨胀系数高于塑封料的热膨胀系数。
8.一种采用如权利要求1-7任一项所述圆片结构的晶圆级扇出封装工艺,其特征是,包括以下步骤:
(1)基板上贴装临时键合膜;
(2)在临时键合膜上贴装金属框架结构(6);所述金属框架结构(6)由若干个阵列排布的金属框架单元(1)构成,相邻金属框架单元(1)由连脚(5)连接;所述金属框架单元(1)的阵列方式与待排布的芯片(2)排布方式保持一致;
(3)贴装芯片,芯片的安装位置位于金属框架结构的内部,由金属框架结构将芯片包围;装片过程中,每一块芯片的装片都以该芯片所在的金属框架单元中心进行装片定位;
(4)晶圆级注塑重构,将金属框架结构和芯片注塑在一起,得到圆片结构;
(5)去除基板及临时键合膜;
(6)晶圆级再布线;
(7)植球;
(8)划片,得到晶圆级封装。
9.如权利要求8所述的晶圆级扇出封装工艺,其特征是:所述步骤(2)中,金属框架结构(6)直接通过机械加工的方式获得,或者通过刻蚀方法获得。
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CN105489516A (zh) * | 2016-01-22 | 2016-04-13 | 中芯长电半导体(江阴)有限公司 | 一种扇出型芯片的封装方法及封装结构 |
CN107481977A (zh) * | 2017-08-21 | 2017-12-15 | 华进半导体封装先导技术研发中心有限公司 | 一种晶圆级扇出型封装结构及封装方法 |
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CN105489516A (zh) * | 2016-01-22 | 2016-04-13 | 中芯长电半导体(江阴)有限公司 | 一种扇出型芯片的封装方法及封装结构 |
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