CN1067488C - 用于半导体晶片的托座及其应用 - Google Patents

用于半导体晶片的托座及其应用 Download PDF

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CN1067488C
CN1067488C CN97112352A CN97112352A CN1067488C CN 1067488 C CN1067488 C CN 1067488C CN 97112352 A CN97112352 A CN 97112352A CN 97112352 A CN97112352 A CN 97112352A CN 1067488 C CN1067488 C CN 1067488C
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bracket
semiconductor wafer
edge
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CN1172346A (zh
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贝恩德·绍特
迪特尔·塞弗特
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Siltronic AG
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/68—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for positioning, orientation or alignment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
    • H01L21/6835—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S294/00—Handling: hand and hoist-line implements
    • Y10S294/902—Gripping element
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S414/00—Material or article handling
    • Y10S414/135—Associated with semiconductor wafer handling
    • Y10S414/141—Associated with semiconductor wafer handling includes means for gripping wafer

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  • Condensed Matter Physics & Semiconductors (AREA)
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Abstract

本发明涉及用于半导体晶片的托座和该托座的应用。该托座至少有三个用来支承半导体晶片边缘的突出部分，以使半导体晶片最终基本上成水平向。该托座不与半导体晶片正面及背面相接触，并且突出部位所具形状要使半导体晶片的边缘仅在该晶片正面和背面之间中央处的虚拟中央平面之下被支承。该托座被优选用于在不低于200℃温度下对半导体晶片进行处理。

Description

用于半导体晶片的托座及其应用
本发明涉及一种用于半导体晶片的托座和它的应用。
半导体晶片以大批量生产并进一步被加工成电子元件。该生产过程还包括在不低于200℃的温度下，处理半导体晶片的过程，例如：纯粹的热处理，或者通过淀积气体的热分解，在受处理半导体晶片的表面上淀积成层。这类处理必须严格确保半导体晶片不会受到有害的外来金属、掺杂物或颗粒物的污染，这些污染物以后是不可能被除去的或者只有添加大量耗费才能去除。
有一些处理工作点，例如，在不低于200℃温度下连续处理半导体晶片的化学气相淀积(CVD)反应器。半导体晶片是被置于一传送带上，并用该传送带将其送入处理工作点。半导体晶片和传送带之间的相对运动以及半导体晶片和传送带之直接接触，增加了半导体晶片受损和被扩散进入半导体材料的外部金属污染的危险。
如果半导体晶片被涂复则存在生长层会使半导体晶片和放置半导体的支承表面之间形成一牢固粘结的危险。难以使粘结半导体晶片与支承面分开，而同时又不损毁或污染半导体晶片。
本发明的目的是，在不低于200℃温度下处理半导体晶片期间，减少半导体晶片，尤其是硅半导体晶片，损毁或污染的危险。
本发明涉及一种用于半导体晶片的托座，具有平整正面、平整背面和圆周边。其中，该托座至少有三个用来支承半导体晶片边缘的突起部位，以使该半导体晶片最终水平放置，并且该托座不与半导体晶片的正面和背面相接触，且该突起部位所具形状，要使要使半导体晶片边缘的位置，仅在半导体晶片的正、背面间中央处一虚拟中央平面之下。
托座在恰当的位置固定半导体晶片，防止半导体晶片和受污染支承面之间的直接接触。在涂层后半导体晶片继续粘结到托座的危险，因托座的形状而被显著地降低了。
参照图示，本发明被更详细地描述如下。
图1a示出了按本发明的一种实施方案的托座和置于托座上半导体晶片的示意图。
图1b是图1a的部分放大图。
图2示出了根据本发明的一项演变的图1b的托座。
从图1a推断，托座1的形状类似于碟子形状。半导体晶片2的圆周边缘4置于托座1上所具的突起部位3上。为了能以稳定方式保持半晶体晶片水平向，托座必须有不少于三个位置彼此相隔的突出部位3。优选的是，构成的托座表面，要形成呈环状、用来放置半导体晶片边缘4的沿口(bead)。该沿口提供能够用来支承半导体晶片并且防止气体传送到半导体晶片背面的特别大的面积。
半导体晶片一般具有两个位置彼此平行的，并由圆周边连接的侧向平面。本发明中，侧面指的是半导体晶片背向托座面向上的正面。与此对应，该半导体晶片的背面是面向下的对置的侧面。
托座1既不与半导体晶片2的正面5相接触，也不与其背面6相接触。该突出部位3所具的形态，要使支承半导体晶片的托座仅位于半导体晶片的边缘，并且具体说来，位于半导体晶片正面5和背面6之间中央处的虚拟中央平面7之下(图1b)。能够以这样的方式在反应器中涂复半导体晶片正面5，不必害怕托座的存在会损害正面边缘处的涂复。
尤其优选的托座突出部位3的构成方式，是要使半导体晶片边缘4仅支承在虚拟平面8之下。虚拟平面8对虚拟中央平面7是平行并且不重合的，它与半导体晶片背面6的距离不大于半导体晶片虚拟中央平面7和背面6之间存在距离d的80％。特别是如果半导体晶片的正面被涂复期间，有利于避免因生长层引起的它对托座的粘结。
按示于图2中本发明的演变，护圈9使得难于将淀积传送难于达到半导体晶片和托座相接触的位置。护圈9按与边缘4等距离的方式，围绕水平的半导体晶片伸展。为了有效地限制气体传送，应当选择护圈高度h，使得护圈向上伸展高度不低于半导体晶片正面5所在平面。
所示的该实施方案中，护圈以可分开的方式与托座连接，并且优选使用仅对半导体晶片边缘起作用的夹具。在托座上放置或从托座上夹起半导体晶片之前，可以将其移去。护圈也可以这一种(未示出)的方式构成，使它包住半导体晶片边缘，在该种方式中，防止该边缘形成不希望的涂复层。
如果护圈9和托座1以不可被分开方式连接，要确保夹具能把半导体晶片放置在托座的突出部分3上。举例而言，借助于带有凹槽的圆环(未示出)，可以做到此点，在放置和移去半导体晶片时，凹槽给夹具提供了必要的空间。
根据图1a所示，托座1具碟子形状，具有连续的基底10。举例而言，连续一体的基底防止淀积气体能够达到半导体晶片的背面6，防止背面同时被涂复。如果半导体晶片的背面和正面要以同一方式加以处理，可以在托座的基底10中提供一中心孔道11，中心孔道11对托座形成圆环形并且仅在图1a中示出。
所说明的托座优选用于在不低于200℃温度下半导体晶片的处理。对于硅半导体晶片的处理而言，托座优选用玻璃、石英玻璃，陶瓷或硅制成。可以选择使托座附加的涂复一防止扩散层，使来自支承表面或该托座的污染物几乎无法扩散到半导体晶片并将其污染。
在处理前，用夹具把半导体晶片置于托座上。该托座可以已被置于输送它的传送机带上，与半导体晶片一起传送进入处理工作点。也可以把多个装半导体晶片的托座彼此迭叠在一支承器中，以批量方式处理半导体晶片。在处理半导体晶片期间，一个托座和一半导体晶片往往构成一个单元。因此，便于定期清洁用过的托座并清除任何淀积层。

Claims (9)

1、一种用于半导体晶片的托座，具有一平整正面、平整背面以及一圆周边，其中，该托座至少具有三个用来支承半导体晶片边缘的突起部位，使半导体晶片水平放置，并且该托座不与该半导体晶片的正面及背面相接触，该突出部位所具形状使得半导体晶片的边缘仅在该半导体晶片正面和背面之间中心处的虚拟中央平面之下被支承。
2、根据权利要求1的托座，其中，该托座的突出部位所具有的形状，使得该半导体晶片的边缘仅在与虚拟中央平面以不重迭方式平行的虚拟平面之下被支承，并且，它与半导体晶片背面的最大距离是该半导体晶片虚拟中央平面和背面之间距离的80％。
3、根据权利要求1或2的托座，其中，护圈置于水平向放置的半导体晶片边缘之周围，并与边缘成等距离。
4、根据权利要求1或2的托座，其中，托座由选自包括玻璃、石英玻璃、陶瓷和硅的材料构成。
5、根据权利要求1或2的托座，其中，托座被涂复有一层抑制污染物扩散的保护层。
6、根据权利要求1或2的托座，其中，所构成的托座的表面形成一呈环状的沿口。
7、根据权利要求1或2的托座，其中，把托座构成为有一中心孔的环状物，该孔使得自由接触半导体晶体背面成为可能。
8、根据权利要求1或2的托座，其中，把托座构成为具有连续基底的碟子状物，该基底完全地盖住半导体晶片的背面。
9、根据在权利要求1至8的任一项的托座在不低于200℃的温度下进行半导体晶片处理中的应用。
CN97112352A 1996-07-31 1997-05-28 用于半导体晶片的托座及其应用 Expired - Fee Related CN1067488C (zh)

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DE19630932A DE19630932A1 (de) 1996-07-31 1996-07-31 Träger für eine Halbleiterscheibe und Verwendung des Trägers

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EP0822589B1 (de) 1999-09-22
DE19630932A1 (de) 1998-02-05
US5911461A (en) 1999-06-15
JPH1098091A (ja) 1998-04-14
JP2923525B2 (ja) 1999-07-26
CN1172346A (zh) 1998-02-04
DE59700461D1 (de) 1999-10-28
EP0822589A1 (de) 1998-02-04
TW365040B (en) 1999-07-21
SG60095A1 (en) 1999-02-22
KR100275281B1 (ko) 2000-12-15
KR19990011830A (ko) 1999-02-18
BR9704140A (pt) 1999-01-26

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