TWI844329B

TWI844329B - Electrostatic chuck

Info

Publication number: TWI844329B
Application number: TW112113226A
Authority: TW
Inventors: 陳肇斌; 吳禹函; 陳正豪; 花士豪
Original assignee: 財團法人工業技術研究院
Filing date: 2023-04-10
Publication date: 2024-06-01

Abstract

An electrostatic chuck includes a substrate, an electrode layer and a base. The substrate has an upper surface, a lower surface and a plurality of grooves. The upper surface is opposite to the lower surface, and the grooves are formed on the upper surface and separate a plurality of regions. The electrode layer is embedded in the substrate, and the electrode layer includes a plurality of electrodes. The electrodes are located in the regions, respectively, and a distance defined between the electrodes and the upper surface is smaller than a depth of the grooves recessed from the upper surface. The base is connected to the lower surface of the substrate for carrying and fixing the substrate.

Description

靜電吸盤Electrostatic suction cup

本發明係關於一種靜電吸盤，特別是一種具有盤面溝槽結構與電極構型相互匹配的靜電吸盤。The present invention relates to an electrostatic chuck, in particular to an electrostatic chuck having a groove structure on the surface of the chuck and an electrode configuration that matches each other.

靜電力吸附式晶圓乘載盤模組(Electrostatic Chuck，ESC，以下簡稱靜電吸盤)是利用靜電力使物體相互吸引，以吸附並固定晶圓等工件。當晶圓被放置在靜電吸盤上且靜電吸盤內部的電極被施加例如為1,500~3,000伏特的正電壓和負電壓時，晶圓中的電荷會移動而被靜電吸盤內部的電極吸引，從而在電極和晶圓之間產生庫侖力(Coulomb force)，使晶圓被吸附在靜電吸盤上。The electrostatic chuck (ESC) uses electrostatic force to attract objects to each other, so as to absorb and fix workpieces such as wafers. When a wafer is placed on the electrostatic chuck and the electrodes inside the electrostatic chuck are applied with positive and negative voltages of, for example, 1,500 to 3,000 volts, the charge in the wafer moves and is attracted by the electrodes inside the electrostatic chuck, thereby generating a Coulomb force between the electrodes and the wafer, causing the wafer to be adsorbed on the electrostatic chuck.

然而，傳統靜電吸盤在高溫製程時，容易因為熱膨脹而產生較大的翹曲變形，導致吸附力不均勻而損傷所承載的晶圓。於此，透過在靜電吸盤的盤面開設呈輻射狀的線型溝槽，以將盤面分隔成多個區域，可降低盤面因高溫產生的翹曲。但是，當靜電吸盤的盤面上開設有溝槽時，埋設於靜電吸盤之基板中與溝槽對應設置的電極層則會更遠離盤面，也就是說，由於溝槽與電極層在基板的中心軸的方向上彼此重疊，因此電極層與盤面之間因為溝槽的設置而有較大的距離(大於溝槽在盤面上凹陷的深度)。如此，由於電極和晶圓之間靜電吸力(庫侖力)的強度係和距離的平方成反比，故電極層與盤面之間的距離愈大，則靜電吸力會愈小，導致晶圓無法固定吸附於靜電吸盤上。However, conventional electrostatic chucks are prone to large warping and deformation due to thermal expansion during high temperature processes, resulting in uneven adsorption and damage to the wafers carried. Here, radial linear grooves are provided on the surface of the electrostatic chuck to divide the surface into multiple areas, thereby reducing the warping of the surface caused by high temperature. However, when a groove is formed on the surface of the electrostatic chuck, the electrode layer corresponding to the groove and buried in the substrate of the electrostatic chuck will be farther away from the surface of the disk. In other words, since the groove and the electrode layer overlap each other in the direction of the central axis of the substrate, there is a greater distance between the electrode layer and the surface of the disk due to the groove (greater than the depth of the groove on the surface of the disk). In this way, since the strength of the electrostatic attraction (Coulomb force) between the electrode and the wafer is inversely proportional to the square of the distance, the greater the distance between the electrode layer and the disk surface, the smaller the electrostatic attraction will be, resulting in the wafer being unable to be fixedly adsorbed on the electrostatic chuck.

本發明在於提供一種靜電吸盤，藉以解決先前技術中電極層與盤面之間因為溝槽的設置而有較大的距離，導致靜電吸力變小使晶圓無法固定吸附於靜電吸盤上的問題。The present invention provides an electrostatic chuck to solve the problem in the prior art that there is a large distance between the electrode layer and the plate surface due to the arrangement of the groove, which causes the electrostatic suction force to be reduced and the wafer cannot be fixedly adsorbed on the electrostatic chuck.

本發明之一實施例所揭露之靜電吸盤，包含一基板、一電極層以及一基座。基板具有一上表面、一下表面以及複數個溝槽。上表面相對於下表面，且溝槽形成於上表面並分隔出複數個區域。電極層埋設於基板中，且電極層包含複數個電極。電極分別位於所述複數個區域中，且電極與上表面之間定義的距離小於溝槽在上表面上凹陷的深度。基座連接於基板的下表面，以承載並固定基板。An electrostatic chuck disclosed in an embodiment of the present invention comprises a substrate, an electrode layer and a base. The substrate has an upper surface, a lower surface and a plurality of grooves. The upper surface is opposite to the lower surface, and the grooves are formed on the upper surface and separate a plurality of regions. The electrode layer is buried in the substrate, and the electrode layer comprises a plurality of electrodes. The electrodes are respectively located in the plurality of regions, and the distance defined between the electrodes and the upper surface is less than the depth of the grooves on the upper surface. The base is connected to the lower surface of the substrate to support and fix the substrate.

根據上述實施例所揭露的靜電吸盤，其電極分別位於溝槽所分隔出的區域中，從而電極的結構圖案和溝槽的結構圖案為相互匹配，此外，電極與溝槽在基板的中心軸的方向上彼此不重疊，且電極與上表面之間的距離小於溝槽在上表面上凹陷的深度，使得電極可更貼近基板的上表面，以縮短電極與放置於上表面的晶圓之間的距離。藉此，縮短電極與基板的上表面之間的距離，可在不增加操作電壓的情況下增加靜電吸力強度，進而有利於節能減排的目標。According to the electrostatic chuck disclosed in the above embodiment, the electrodes are respectively located in the areas separated by the grooves, so that the structural patterns of the electrodes and the structural patterns of the grooves are matched with each other. In addition, the electrodes and the grooves do not overlap each other in the direction of the central axis of the substrate, and the distance between the electrodes and the upper surface is less than the depth of the grooves on the upper surface, so that the electrodes can be closer to the upper surface of the substrate to shorten the distance between the electrodes and the wafer placed on the upper surface. In this way, by shortening the distance between the electrodes and the upper surface of the substrate, the electrostatic suction strength can be increased without increasing the operating voltage, which is beneficial to the goal of energy saving and emission reduction.

以上關於本發明內容的說明及以下實施方式的說明係用以示範與解釋本發明的原理，並且提供本發明的專利申請範圍更進一步的解釋。The above description of the content of the present invention and the following description of the implementation method are used to demonstrate and explain the principle of the present invention and provide a further explanation of the scope of the patent application of the present invention.

以下在實施方式中詳細敘述本發明之實施例之詳細特徵以及優點，其內容足以使任何本領域中具通常知識者了解本發明之實施例之技術內容並據以實施，且根據本說明書所揭露之內容、申請專利範圍及圖式，任何本領域中具通常知識者可輕易地理解本發明相關之目的及優點。以下之實施例係進一步詳細說明本發明之觀點，但非以任何觀點限制本發明之範疇。The following detailed description of the features and advantages of the embodiments of the present invention is provided in the embodiments, and the contents are sufficient to enable any person with ordinary knowledge in the field to understand the technical contents of the embodiments of the present invention and implement them accordingly. Moreover, according to the contents disclosed in this specification, the scope of the patent application and the drawings, any person with ordinary knowledge in the field can easily understand the relevant purposes and advantages of the present invention. The following embodiments are further detailed descriptions of the viewpoints of the present invention, but are not intended to limit the scope of the present invention by any viewpoint.

請參照圖1至圖3，其中圖1為根據本發明之第一實施例所述之靜電吸盤的立體示意圖，圖2為圖1之靜電吸盤的分解示意圖，且圖3為圖1之靜電吸盤的上視圖。Please refer to Figures 1 to 3, wherein Figure 1 is a three-dimensional schematic diagram of the electrostatic chuck according to the first embodiment of the present invention, Figure 2 is an exploded schematic diagram of the electrostatic chuck of Figure 1, and Figure 3 is a top view of the electrostatic chuck of Figure 1.

本實施例之靜電吸盤1例如為具有6吋盤面的圓盤狀靜電吸盤，用以吸附並固定晶圓等工件(未繪示)。靜電吸盤1包含一基板10、一電極層11以及一基座12。其中，電極層11係埋設於基板10中，且基座12用以承載並固定基板10。應理解的是，所述6吋盤面之尺寸僅為示例，本發明不以此尺寸大小為限。The electrostatic chuck 1 of this embodiment is, for example, a disc-shaped electrostatic chuck with a 6-inch disk surface, which is used to absorb and fix a workpiece such as a wafer (not shown). The electrostatic chuck 1 includes a substrate 10, an electrode layer 11, and a base 12. The electrode layer 11 is embedded in the substrate 10, and the base 12 is used to support and fix the substrate 10. It should be understood that the size of the 6-inch disk surface is only an example, and the present invention is not limited to this size.

在圖2中，為方便呈現埋設於基板10中的電極層11，基板10係繪示成上基板P1和下基板P2的方式分解呈現，然本實施例之上基板P1和下基板P2為相同材質並例如透過高溫燒結一體成型的結構，其中電極層11係夾設於上基板P1和下基板P2之間而埋設於基板10之中。In Figure 2, in order to conveniently present the electrode layer 11 buried in the substrate 10, the substrate 10 is depicted as being decomposed into an upper substrate P1 and a lower substrate P2. However, in this embodiment, the upper substrate P1 and the lower substrate P2 are made of the same material and are integrally formed, for example, by high-temperature sintering, wherein the electrode layer 11 is sandwiched between the upper substrate P1 and the lower substrate P2 and buried in the substrate 10.

基板10具有一上表面100、一下表面101、一軸心CP以及複數個溝槽102，其中上表面100相對於下表面101，且溝槽102形成於上表面100。此外，基座12係連接於基板10的下表面101以承載並固定基板10。The substrate 10 has an upper surface 100, a lower surface 101, a center CP and a plurality of grooves 102, wherein the upper surface 100 is opposite to the lower surface 101 and the grooves 102 are formed on the upper surface 100. In addition, the base 12 is connected to the lower surface 101 of the substrate 10 to support and fix the substrate 10.

於本實施例中，所述複數個溝槽102係為複數個同心圓溝槽CG以及複數個線型溝槽SG，且這些同心圓溝槽CG與線型溝槽SG交錯設置並分隔出複數個區域RR，然於其他實施例中，所述複數個溝槽102也可是其它形狀的溝槽，並不以同心圓及線型為限。在本實施例中，同心圓溝槽CG的數量為兩個，且這些同心圓溝槽CG具有不同的半徑並實質上以基板10的軸心CP為圓心形成於基板10的上表面100。線型溝槽SG的數量為六個，且這些線型溝槽SG實質上從基板10的軸心CP以輻射狀朝上表面100的邊緣(即圓周緣)線性延伸。In this embodiment, the plurality of grooves 102 are a plurality of concentric circular grooves CG and a plurality of linear grooves SG, and these concentric circular grooves CG and linear grooves SG are arranged alternately and separate a plurality of regions RR, but in other embodiments, the plurality of grooves 102 may also be grooves of other shapes, not limited to concentric circles and lines. In this embodiment, the number of concentric circular grooves CG is two, and these concentric circular grooves CG have different radii and are substantially formed on the upper surface 100 of the substrate 10 with the axis CP of the substrate 10 as the center. The number of the linear grooves SG is six, and these linear grooves SG substantially extend linearly from the axis CP of the substrate 10 in a radial shape toward the edge (ie, the circumferential edge) of the upper surface 100 .

請一併參照圖4和圖5，其中圖4為圖2之靜電吸盤的電極層的電極的上視圖，且圖5為根據本發明之第一實施例所述之靜電吸盤的局部剖面示意圖。Please refer to FIG. 4 and FIG. 5 together, wherein FIG. 4 is a top view of the electrode of the electrode layer of the electrostatic chuck of FIG. 2 , and FIG. 5 is a partial cross-sectional schematic view of the electrostatic chuck according to the first embodiment of the present invention.

電極層11包含複數個電極PE、NE以及複數個連接片110，其中電極PE、NE分別位於溝槽102所分隔出的區域RR中，且電極PE、NE與基板10的上表面100之間定義的一距離DS(例如電極PE、NE與上表面100的最小直線距離)小於溝槽102在上表面100上凹陷的一深度DP。其中，電極PE、NE與上表面100之間的距離DS例如大於等於0.1公釐(mm)且小於等於0.7 mm。較佳地，電極PE、NE與上表面100之間的距離DS例如大於等於0.4 mm且小於等於0.6 mm。藉此，縮短電極與基板的上表面之間的距離，可在不增加操作電壓的情況下增加靜電吸力強度，進而有利於節能減排的目標。The electrode layer 11 includes a plurality of electrodes PE, NE and a plurality of connecting sheets 110, wherein the electrodes PE, NE are respectively located in the region RR separated by the trench 102, and a distance DS defined between the electrodes PE, NE and the upper surface 100 of the substrate 10 (e.g., the minimum straight line distance between the electrodes PE, NE and the upper surface 100) is less than a depth DP of the trench 102 recessed on the upper surface 100. The distance DS between the electrodes PE, NE and the upper surface 100 is, for example, greater than or equal to 0.1 millimeters (mm) and less than or equal to 0.7 mm. Preferably, the distance DS between the electrodes PE, NE and the upper surface 100 is, for example, greater than or equal to 0.4 mm and less than or equal to 0.6 mm. By shortening the distance between the electrode and the upper surface of the substrate, the electrostatic attraction strength can be increased without increasing the operating voltage, thereby achieving the goal of energy saving and emission reduction.

在本實施例中，電極PE、NE的厚度為30微米(μm)，但本發明不以此為限。在其他實施例中，電極PE、NE的厚度可大於等於0.1 μm且小於等於100 μm。應理解的是，圖式中各元件之間的尺寸比例僅為示意，其並非依實際尺寸繪製。In this embodiment, the thickness of the electrodes PE and NE is 30 micrometers (μm), but the present invention is not limited thereto. In other embodiments, the thickness of the electrodes PE and NE may be greater than or equal to 0.1 μm and less than or equal to 100 μm. It should be understood that the size ratios between the components in the drawings are only for illustration and are not drawn according to the actual size.

由圖2至圖4可見，電極PE、NE的結構圖案和形成於上表面100的溝槽102的結構圖案為相互匹配，且電極PE、NE與溝槽102在基板10的中心軸CL的方向上彼此不重疊，使得電極PE、NE可更貼近基板10的上表面100，以縮短電極PE、NE與放置於上表面100的晶圓(未繪示)之間的距離。As can be seen from Figures 2 to 4, the structural patterns of the electrodes PE and NE and the structural patterns of the grooves 102 formed on the upper surface 100 match each other, and the electrodes PE and NE and the grooves 102 do not overlap with each other in the direction of the center axis CL of the substrate 10, so that the electrodes PE and NE can be closer to the upper surface 100 of the substrate 10 to shorten the distance between the electrodes PE and NE and the wafer (not shown) placed on the upper surface 100.

所述複數個電極PE、NE係為複數個正電極PE以及複數個負電極NE，且溝槽102所分隔出的這些區域RR中各自對應設有一個正電極PE或一個負電極NE。如圖4所示，在本實施例中，正電極PE與負電極NE在周向上為交錯排列設置，但本發明不以本實施例中正、負電極的配置方式為限。The plurality of electrodes PE and NE are a plurality of positive electrodes PE and a plurality of negative electrodes NE, and each of the regions RR separated by the groove 102 is provided with a positive electrode PE or a negative electrode NE. As shown in FIG4 , in this embodiment, the positive electrodes PE and the negative electrodes NE are arranged in a staggered manner in the circumferential direction, but the present invention is not limited to the configuration of the positive and negative electrodes in this embodiment.

在本實施例中，正電極PE與基板10的上表面100之間的距離DS相等於負電極NE與基板10的上表面100之間的距離DS，從而可確保靜電吸附力的均勻性，但不以此為限。In this embodiment, the distance DS between the positive electrode PE and the upper surface 100 of the substrate 10 is equal to the distance DS between the negative electrode NE and the upper surface 100 of the substrate 10, thereby ensuring the uniformity of the electrostatic adsorption force, but not limited thereto.

由於這些電極PE、NE係分別位於不同的區域RR中且被溝槽102所分隔開，故可透過將連接片110分別跨設於這些溝槽102，以連接相鄰兩區域RR中具有相同極性的兩個電極(即連接兩個正電極PE或連接兩個負電極NE)。舉例來說，如圖5所示，相鄰的兩個正電極PE之間被溝槽102所分隔開，故可透過跨設於溝槽102的連接片110將這兩個相鄰的正電極PE電性連接。Since these electrodes PE and NE are located in different regions RR and separated by the trenches 102, two electrodes with the same polarity in two adjacent regions RR (i.e., two positive electrodes PE or two negative electrodes NE) can be connected by placing connecting pieces 110 across these trenches 102. For example, as shown in FIG. 5 , two adjacent positive electrodes PE are separated by the trenches 102, so the two adjacent positive electrodes PE can be electrically connected by placing connecting pieces 110 across the trenches 102.

在本實施例中，基板10為氮化鋁(AlN)陶瓷基板，基座12為鋁基座，且電極層11的材質為鎢合金。其中，所述鎢合金包含45~65wt%的鎢粉、15~35wt%之不同於鎢的金屬(例如鎂、鈣、鋁、鈦)及金屬氧化物以及20wt%或以上的黏結劑。此外，電極層11例如透過包含上述成分的鎢合金漿液經高溫燒結成為固態金屬電極而形成。應理解的是，上述各成份的比例可依實際設計需求而在所界定的範圍內調整，且各成份所佔比例之加總不應超過100wt%。In this embodiment, the substrate 10 is an aluminum nitride (AlN) ceramic substrate, the base 12 is an aluminum base, and the material of the electrode layer 11 is a tungsten alloy. The tungsten alloy contains 45-65wt% of tungsten powder, 15-35wt% of metals other than tungsten (such as magnesium, calcium, aluminum, titanium) and metal oxides, and 20wt% or more of a binder. In addition, the electrode layer 11 is formed, for example, by sintering a tungsten alloy slurry containing the above components at a high temperature to form a solid metal electrode. It should be understood that the proportion of the above components can be adjusted within the defined range according to actual design requirements, and the total proportion of each component should not exceed 100wt%.

在本實施例中，由鎢合金材料製成的電極層11的熱膨脹係數可約為8.04×10 ^-6k，且材料為氮化鋁的基板10的熱膨脹係數可約為7.19×10 ^-6k。相較於現有技術中熱膨脹係數為4.5×10 ^-6k的電極層，本實施例之鎢合金電極層11具有與氮化鋁陶瓷基板10較相近的熱膨脹係數，從而靜電吸盤1在高溫製程時，電極層11與基板10的熱膨脹程度較為相近，可減少兩者之間變形量的差異。此外，在電極層11的材料中添加鎂、鈣、鋁、鈦等活性元素，可強化金屬與陶瓷之間的接合強度，並可減少金屬與陶瓷之間熱膨脹係數的差異。所述高溫製程例如為碳化矽(SiC)與氮化鎵(GaN)之高溫製程，其可使製程環境快速升溫至500℃至800℃。 In the present embodiment, the thermal expansion coefficient of the electrode layer 11 made of tungsten alloy material can be about 8.04× ^10-6 K, and the thermal expansion coefficient of the substrate 10 made of aluminum nitride material can be about 7.19× ^10-6 K. Compared with the electrode layer with a thermal expansion coefficient of 4.5× ^10-6 K in the prior art, the tungsten alloy electrode layer 11 of the present embodiment has a thermal expansion coefficient that is closer to that of the aluminum nitride ceramic substrate 10, so that when the electrostatic chuck 1 is processed at a high temperature, the thermal expansion degree of the electrode layer 11 and the substrate 10 is closer, which can reduce the difference in deformation between the two. In addition, adding active elements such as magnesium, calcium, aluminum, and titanium to the material of the electrode layer 11 can enhance the bonding strength between the metal and the ceramic and reduce the difference in thermal expansion coefficient between the metal and the ceramic. The high temperature process is, for example, a high temperature process of silicon carbide (SiC) and gallium nitride (GaN), which can rapidly heat the process environment to 500°C to 800°C.

一般來說，靜電吸盤在高溫製程時，基板會因為熱膨脹而些許變形，其中在基板的上表面的邊緣通常會有最大的變形量，使得上表面的近軸心處與邊緣之間具有高度上的差異，導致上表面變得不平整而使基板與晶圓之間的間隙過大，進而影響靜電吸盤對晶圓的吸附力均勻程度。於此，本實施例的基板10的上表面100除了開設有多個線型溝槽SG之外，還開設有多個同心圓溝槽CG，以將基板10的上表面100進一步分隔成多個區域RR，從而減少每個區域RR各自的面積，進而降低上表面100因高溫產生的翹曲。相較於現有技術中靜電吸盤的盤面僅開設有呈輻射狀的線型溝槽，本實施例之靜電吸盤1在高溫製程時，基板10可有較小的最大變形量。舉例來說，所述現有的靜電吸盤在例如為1000℃的高溫製程環境時，其6吋盤面邊緣與近軸心CP處的高度差異約為54.91 μm，而本實施例的靜電吸盤1在例如為1000℃的高溫製程環境時，基板10的上表面100的邊緣與近軸心CP處的高度差異約為38.94 μm。由此可見，本實施例的溝槽102的結構可有效減小基板10熱膨脹時的最大變形量。Generally speaking, when the electrostatic chuck is in a high temperature process, the substrate will be slightly deformed due to thermal expansion, and the edge of the upper surface of the substrate will usually have the largest deformation, resulting in a height difference between the near-axis center of the upper surface and the edge, causing the upper surface to become uneven and the gap between the substrate and the wafer to be too large, thereby affecting the uniformity of the electrostatic chuck's adsorption force on the wafer. Here, in addition to a plurality of linear grooves SG, the upper surface 100 of the substrate 10 of the present embodiment is also provided with a plurality of concentric grooves CG to further divide the upper surface 100 of the substrate 10 into a plurality of regions RR, thereby reducing the area of each region RR, thereby reducing the warp of the upper surface 100 caused by high temperature. Compared to the electrostatic chuck in the prior art, which has only radial linear grooves on its surface, the electrostatic chuck 1 of the present embodiment can have a smaller maximum deformation of the substrate 10 during a high temperature process. For example, when the conventional electrostatic chuck is in a high temperature process environment of, for example, 1000°C, the height difference between the edge of the 6-inch surface and the near axis CP is about 54.91 μm, while when the electrostatic chuck 1 of the present embodiment is in a high temperature process environment of, for example, 1000°C, the height difference between the edge of the upper surface 100 of the substrate 10 and the near axis CP is about 38.94 μm. It can be seen that the structure of the groove 102 of this embodiment can effectively reduce the maximum deformation of the substrate 10 during thermal expansion.

進一步地，在本實施例的靜電吸盤1中，當電極PE、NE與基板10的上表面100之間的距離DS改變時，上表面100的邊緣與近軸心CP處在基板10發生熱膨脹時的高度差異量也不同。舉例來說，如下表一所示，當所有電極PE、NE與上表面100之間的距離DS皆設計為0.4 mm、0.5 mm或0.6 mm時，靜電吸盤1在1000℃的高溫製程環境中，上表面100的邊緣與近軸心CP處的高度差異分別約為39.32 μm、38.94 μm和38.25 μm(其皆小於現有的靜電吸盤在相同溫度下發生熱膨脹時所產生的最大高度差異量54.91 μm)。Furthermore, in the electrostatic chuck 1 of the present embodiment, when the distance DS between the electrodes PE, NE and the upper surface 100 of the substrate 10 changes, the height difference between the edge of the upper surface 100 and the proximal axis CP when the substrate 10 undergoes thermal expansion also varies. For example, as shown in Table 1 below, when the distance DS between all electrodes PE, NE and the upper surface 100 is designed to be 0.4 mm, 0.5 mm or 0.6 mm, the height difference between the edge of the upper surface 100 and the near-axis CP of the electrostatic chuck 1 in a high-temperature process environment of 1000°C is approximately 39.32 μm, 38.94 μm and 38.25 μm respectively (which are all smaller than the maximum height difference of 54.91 μm generated by the thermal expansion of the existing electrostatic chuck at the same temperature).

表一 Table I 電極與上表面之間的距離 Distance between electrode and top surface 上表面的邊緣與近軸心處的高度差異 The height difference between the edge of the upper surface and the near axis 0.6 mm 0.6 mm 38.25 μm 38.25 μm 0.5 mm 0.5 mm 38.94 μm 38.94 μm 0.4 mm 0.4 mm 39.32 μm 39.32 μm

在本實施例中，相鄰區域RR中相同極性的電極透過連接片110電性連接，從而可減少用來將電極層11與外部元件(例如電壓源)電性連接的導線的數量，進而可減少基板10的穿孔的數量，但本發明不以此為限。在其他實施例中，電極層可依實際設計需求而不具有連接片，且每個電極皆可透過導線與外部元件電性連接。In this embodiment, electrodes of the same polarity in adjacent regions RR are electrically connected through the connecting sheet 110, thereby reducing the number of wires used to electrically connect the electrode layer 11 with external elements (such as a voltage source), thereby reducing the number of through-holes in the substrate 10, but the present invention is not limited thereto. In other embodiments, the electrode layer may not have a connecting sheet according to actual design requirements, and each electrode may be electrically connected to an external element through a wire.

本實施例之基板10為氮化鋁陶瓷基板，但本發明不以此為限。在其他實施例中，基板10可例如為氧化鋁(Al ₂O ₃)陶瓷基板、氧化鋁-碳化矽(Al ₂O ₃-SiC)陶瓷基板或氧化釔(Y ₂O ₃)陶瓷基板等其他材質的基板。此外，本實施例之基座12為鋁基座，但本發明不以此為限。在其他實施例中，基座12可例如為不鏽鋼基座、玻璃基座或塑膠基座等。此外，本實施例之電極層11的材質為鎢合金，但本發明不以此為限。在其他實施例中，電極層11的材質可例如為鉭合金或鉬合金等。 The substrate 10 of the present embodiment is an aluminum nitride ceramic substrate, but the present invention is not limited thereto. In other embodiments, the substrate 10 may be a substrate of other materials such as an aluminum oxide (Al ₂ O ₃ ) ceramic substrate, an aluminum oxide-silicon carbide (Al ₂ O ₃ -SiC) ceramic substrate or a yttrium oxide (Y ₂ O ₃ ) ceramic substrate. In addition, the base 12 of the present embodiment is an aluminum base, but the present invention is not limited thereto. In other embodiments, the base 12 may be, for example, a stainless steel base, a glass base or a plastic base. In addition, the material of the electrode layer 11 of the present embodiment is a tungsten alloy, but the present invention is not limited thereto. In other embodiments, the material of the electrode layer 11 may be, for example, a tungsten alloy or a molybdenum alloy.

本實施例之靜電吸盤1為圓盤狀，但本發明不以此為限。在其他實施例中，靜電吸盤1可依實際需求而為不同的幾何形狀。The electrostatic chuck 1 of this embodiment is in the shape of a disk, but the present invention is not limited thereto. In other embodiments, the electrostatic chuck 1 can be in different geometric shapes according to actual needs.

本實施例之複數個溝槽102係為同心圓溝槽CG以及線型溝槽SG，但本發明不以此為限。在其他實施例中，基板10的上表面100上可依實際設計需求而僅開設有同心圓溝槽CG或僅開設有線型溝槽SG。此外，本發明不以本實施例中上表面100所呈現之區域RR的形狀為限，在其他實施例中，溝槽102可具有不同的形狀配置而圍繞分隔出例如為四邊形或其他多邊形的區域RR。The plurality of grooves 102 of this embodiment are concentric circular grooves CG and linear grooves SG, but the present invention is not limited thereto. In other embodiments, the upper surface 100 of the substrate 10 may be provided with only concentric circular grooves CG or only linear grooves SG according to actual design requirements. In addition, the present invention is not limited to the shape of the region RR presented on the upper surface 100 in this embodiment. In other embodiments, the grooves 102 may have different shapes and configurations to surround and separate the region RR, for example, a quadrilateral or other polygon.

在本實施例中，電極PE、NE與上表面100之間的距離DS例如大於等於0.1 mm且小於等於0.7 mm，但本發明不以此為限。在其他實施例中，電極與上表面之間的距離可依實際設計需求而例如小於0.1 mm或大於0.7 mm。In this embodiment, the distance DS between the electrodes PE, NE and the upper surface 100 is, for example, greater than or equal to 0.1 mm and less than or equal to 0.7 mm, but the present invention is not limited thereto. In other embodiments, the distance between the electrode and the upper surface may be, for example, less than 0.1 mm or greater than 0.7 mm according to actual design requirements.

請參照圖6和圖7，其中圖6為根據本發明之第二實施例所述之靜電吸盤的上視圖，且圖7為圖6之靜電吸盤的電極層的電極的上視圖。第二實施例之靜電吸盤1b與前述第一實施例之靜電吸盤1相似，並以相同的標號來表示相同的元件，各元件具備的功能與效果皆與前述相同，於此不再贅述。Please refer to Figures 6 and 7, wherein Figure 6 is a top view of the electrostatic chuck according to the second embodiment of the present invention, and Figure 7 is a top view of the electrode of the electrode layer of the electrostatic chuck of Figure 6. The electrostatic chuck 1b of the second embodiment is similar to the electrostatic chuck 1 of the first embodiment, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

在本實施例中，同心圓溝槽CG的數量為三個，且這些同心圓溝槽CG具有不同的半徑並實質上以基板10的軸心CP為圓心形成於基板10的上表面100。其中，位於上表面100的軸心CP處的區域RR係由具有最小半徑的同心圓溝槽CG所圍繞成的一圓形區域RR。線型溝槽SG的數量為六個，且這些線型溝槽SG從所述圓形區域RR的周緣以輻射狀朝上表面100的邊緣線性延伸，也就是說，這些線型溝槽SG連通具有最小半徑的同心圓溝槽CG，並自其呈輻射狀地向上表面100的邊緣延伸。In this embodiment, there are three concentric circular grooves CG, and these concentric circular grooves CG have different radii and are substantially formed on the upper surface 100 of the substrate 10 with the axis CP of the substrate 10 as the center. The region RR located at the axis CP of the upper surface 100 is a circular region RR surrounded by the concentric circular grooves CG with the smallest radius. There are six linear grooves SG, and these linear grooves SG extend linearly from the periphery of the circular region RR in a radial shape toward the edge of the upper surface 100, that is, these linear grooves SG are connected to the concentric circular grooves CG with the smallest radius and extend from them to the edge of the upper surface 100 in a radial shape.

在本實施例中，位於上表面100的軸心CP處的區域RR係由單一同心圓溝槽CG所界定。另外，上表面100上其他的區域RR則分別可由多個溝槽102所共同分隔界定，例如由相鄰兩個線型溝槽SG以及相鄰兩個同心圓溝槽CG所共同分隔界定，或者由相鄰兩個輻射狀線型溝槽SG以及具有最大半徑的同心圓溝槽CG所共同分隔界定。In this embodiment, the region RR located at the axis CP of the upper surface 100 is defined by a single concentric circular groove CG. In addition, other regions RR on the upper surface 100 may be defined by a plurality of grooves 102, such as two adjacent linear grooves SG and two adjacent concentric circular grooves CG, or two adjacent radial linear grooves SG and a concentric circular groove CG with a maximum radius.

本實施例的靜電吸盤1b在例如為1000℃的高溫製程環境時，基板10的上表面100的邊緣與近軸心CP處的高度差異約為36.94 μm。When the electrostatic chuck 1 b of the present embodiment is placed in a high temperature process environment of, for example, 1000° C., the height difference between the edge of the upper surface 100 of the substrate 10 and the proximal axis CP is approximately 36.94 μm.

進一步地，在本實施例的靜電吸盤1b中，當電極PE、NE與基板10的上表面100之間的距離DS改變時，上表面100的邊緣與近軸心CP處在基板10發生熱膨脹時的高度差異量也不同。舉例來說，如下表二所示，當所有電極PE、NE與上表面100之間的距離DS皆設計為0.4 mm、0.5 mm或0.6 mm時，靜電吸盤1b在1000℃的高溫製程環境中，上表面100的邊緣與近軸心CP處的高度差異分別約為36.81 μm、36.94 μm和37.20 μm(其皆小於現有的靜電吸盤在相同溫度下發生熱膨脹時所產生的最大高度差異量54.91 μm)。Furthermore, in the electrostatic chuck 1b of the present embodiment, when the distance DS between the electrodes PE, NE and the upper surface 100 of the substrate 10 changes, the height difference between the edge of the upper surface 100 and the proximal axis CP when the substrate 10 undergoes thermal expansion also varies. For example, as shown in Table 2 below, when the distance DS between all electrodes PE, NE and the upper surface 100 is designed to be 0.4 mm, 0.5 mm or 0.6 mm, the height difference between the edge of the upper surface 100 and the near-axis CP of the electrostatic chuck 1b in a high-temperature process environment of 1000°C is approximately 36.81 μm, 36.94 μm and 37.20 μm respectively (all of which are smaller than the maximum height difference of 54.91 μm produced by the thermal expansion of the existing electrostatic chuck at the same temperature).

表二 Table II 電極與上表面之間的距離 Distance between electrode and top surface 上表面的邊緣與近軸處的高度差異 Height difference between the edge of the upper surface and the proximal axis 0.6 mm 0.6 mm 37.20 μm 37.20 μm 0.5 mm 0.5 mm 36.94 μm 36.94 μm 0.4 mm 0.4 mm 36.81 μm 36.81 μm

由圖6和圖7可見，電極PE、NE的結構圖案和形成於上表面100的溝槽102的結構圖案為相互匹配，且電極PE、NE與溝槽102在基板10的中心軸CL的方向上彼此不重疊，使得電極PE、NE可更貼近基板10的上表面100，以縮短電極PE、NE與放置於上表面100的晶圓(未繪示)之間的距離。As can be seen from Figures 6 and 7, the structural patterns of the electrodes PE and NE and the structural patterns of the grooves 102 formed on the upper surface 100 match each other, and the electrodes PE and NE and the grooves 102 do not overlap with each other in the direction of the center axis CL of the substrate 10, so that the electrodes PE and NE can be closer to the upper surface 100 of the substrate 10 to shorten the distance between the electrodes PE and NE and the wafer (not shown) placed on the upper surface 100.

在本實施例中，每個區域RR中各自可對應設有至少一個電極PE、NE。詳細來說，如圖6和圖7所示，位於上表面100近軸心CP處的區域RR中係對應設有一個負電極NE，而其他區域RR中則係各自對應設有一個正電極PE和一個負電極NE。此外，除了位於軸心CP處的負電極NE，其他的負電極NE以及正電極PE各自包含沿徑向延伸的直線部以及從所述直線部沿周向延伸的至少一曲線部，且這些負電極NE的曲線部和正電極PE的曲線部在徑向上為交錯排列設置，但本發明不以本實施例中正、負電極的配置方式為限。In this embodiment, at least one electrode PE, NE may be disposed in each region RR. Specifically, as shown in FIG6 and FIG7 , a negative electrode NE is disposed in the region RR near the axis CP of the upper surface 100, and a positive electrode PE and a negative electrode NE are disposed in the other regions RR. In addition, except for the negative electrode NE located at the axis CP, the other negative electrodes NE and the positive electrode PE each include a straight portion extending in the radial direction and at least one curved portion extending from the straight portion in the circumferential direction, and the curved portions of these negative electrodes NE and the curved portions of the positive electrode PE are arranged alternately in the radial direction, but the present invention is not limited to the configuration of the positive and negative electrodes in this embodiment.

如圖7所示，在不同區域RR中被溝槽102所分隔開的相鄰兩正電極PE透過連接片110彼此電性連接。同樣地，在不同區域RR中被溝槽102所分隔開的相鄰兩負電極NE亦透過連接片110彼此電性連接。7 , two adjacent positive electrodes PE separated by the trench 102 in different regions RR are electrically connected to each other through the connecting sheet 110 . Similarly, two adjacent negative electrodes NE separated by the trench 102 in different regions RR are also electrically connected to each other through the connecting sheet 110 .

請參照圖8，其為根據本發明之第二實施例所述之靜電吸盤的局部剖面示意圖。於本實施例中，在同時包含負電極NE和正電極PE的區域RR中，相鄰的兩個電極PE、NE之間定義的一電極距離D1可大於等於1.0 mm且小於等於1.2 mm。舉例來說，如圖8所示，在同時包含負電極NE和正電極PE的區域RR中，負電極NE的曲線部和正電極PE的曲線部在徑向上交錯排列設置，且負電極NE和正電極PE相鄰的曲線部之間的電極距離D1可大於等於1.0 mm且小於等於1.2 mm。另外，在相鄰的兩個區域RR中，被溝槽102所間隔開的相鄰電極PE、NE之間的一間距D2可約為2.0 mm。藉此，透過使正、負電極交錯排列設置，並減小相鄰兩電極之間的電極距離，可增加電極的佈設總面積。相較於現有技術中相鄰電極之間的距離皆為2.0 mm或以上，本實施例中部分相鄰電極PE、NE之間的電極距離可減小至約為1.0 mm，從而本實施例之電極PE、NE佈設總面積相較於現有技術之電極佈設總面積可增加約8.9%。由於電極和晶圓之間靜電吸力(庫侖力)的強度係和電極總面積成正比，故在相同的操作電壓下，本實施例的靜電吸盤1b所產生的靜電吸力會大於現有技術的靜電吸盤所產生的靜電吸力。Please refer to Fig. 8, which is a partial cross-sectional schematic diagram of the electrostatic chuck according to the second embodiment of the present invention. In this embodiment, in the region RR including both the negative electrode NE and the positive electrode PE, an electrode distance D1 defined between two adjacent electrodes PE and NE may be greater than or equal to 1.0 mm and less than or equal to 1.2 mm. For example, as shown in FIG8 , in a region RR including both the negative electrode NE and the positive electrode PE, the curved portion of the negative electrode NE and the curved portion of the positive electrode PE are arranged alternately in the radial direction, and the electrode distance D1 between the adjacent curved portions of the negative electrode NE and the positive electrode PE may be greater than or equal to 1.0 mm and less than or equal to 1.2 mm. In addition, in two adjacent regions RR, a distance D2 between adjacent electrodes PE and NE separated by the groove 102 may be approximately 2.0 mm. Thus, by arranging the positive and negative electrodes in a staggered manner and reducing the electrode distance between two adjacent electrodes, the total electrode layout area can be increased. Compared with the prior art in which the distance between adjacent electrodes is 2.0 mm or more, the electrode distance between some adjacent electrodes PE and NE in this embodiment can be reduced to about 1.0 mm, so that the total electrode layout area of the electrodes PE and NE in this embodiment can be increased by about 8.9% compared with the total electrode layout area of the prior art. Since the strength of the electrostatic attraction (Coulomb force) between the electrode and the wafer is proportional to the total area of the electrode, under the same operating voltage, the electrostatic attraction generated by the electrostatic chuck 1b of this embodiment is greater than the electrostatic attraction generated by the electrostatic chuck of the prior art.

在本實施例中，在同時包含負電極NE和正電極PE的區域RR中，相鄰兩電極PE、NE之間的電極距離D1可大於等於1.0 mm且小於等於1.2 mm，但本發明不以此為限。在其他實施例中，在同時包含負電極和正電極的區域中，相鄰兩電極PE、NE之間的電極距離D1可依實際設計需求或製造技術上的改良而大於1.2 mm或小於1.0 mm。In this embodiment, in the region RR including both the negative electrode NE and the positive electrode PE, the electrode distance D1 between the two adjacent electrodes PE and NE may be greater than or equal to 1.0 mm and less than or equal to 1.2 mm, but the present invention is not limited thereto. In other embodiments, in the region including both the negative electrode and the positive electrode, the electrode distance D1 between the two adjacent electrodes PE and NE may be greater than 1.2 mm or less than 1.0 mm according to actual design requirements or improvements in manufacturing technology.

請參照圖9和圖10，其中圖9為根據本發明之第三實施例所述之靜電吸盤的上視圖，且圖10為圖9之靜電吸盤的電極層的上視圖。第三實施例之靜電吸盤1c與前述實施例之靜電吸盤1、1b相似，並以相同的標號來表示相同的元件，各元件具備的功能與效果皆與前述相同，於此不再贅述。Please refer to Figures 9 and 10, wherein Figure 9 is a top view of the electrostatic chuck according to the third embodiment of the present invention, and Figure 10 is a top view of the electrode layer of the electrostatic chuck of Figure 9. The electrostatic chuck 1c of the third embodiment is similar to the electrostatic chucks 1 and 1b of the aforementioned embodiments, and the same reference numerals are used to represent the same components, and the functions and effects of each component are the same as those described above, and will not be repeated here.

在本實施例中，同心圓溝槽CG的數量為兩個，且線型溝槽SG的數量為四個，其中這些線型溝槽SG從軸心CP處的圓形區域RR的周緣以輻射狀朝上表面100的邊緣線性延伸。In this embodiment, the number of the concentric circular grooves CG is two, and the number of the linear grooves SG is four, wherein the linear grooves SG extend linearly from the periphery of the circular region RR at the axis CP toward the edge of the upper surface 100 in a radial shape.

本實施例的靜電吸盤1c在例如為1000℃的高溫製程環境時，基板的上表面100的邊緣與近軸心CP處的高度差異約為45.76 μm。When the electrostatic chuck 1c of the present embodiment is placed in a high temperature process environment of, for example, 1000°C, the height difference between the edge of the upper surface 100 of the substrate and the proximal axis CP is approximately 45.76 μm.

進一步地，在本實施例的靜電吸盤1c中，當電極PE、NE與基板10的上表面100之間的距離DS改變時，上表面100的邊緣與近軸心CP處在基板10發生熱膨脹時的高度差異量也不同。舉例來說，如下表三所示，當所有電極PE、NE與上表面100之間的距離DS皆設計為0.4 mm、0.5 mm或0.6 mm時，靜電吸盤1c在1000℃的高溫製程環境中，上表面100的邊緣與近軸心CP處的高度差異分別約為44.94 μm、45.76 μm和45.64 μm(其皆小於現有的靜電吸盤在相同溫度下發生熱膨脹時所產生的最大高度差異量54.91 μm)。Furthermore, in the electrostatic chuck 1c of the present embodiment, when the distance DS between the electrodes PE, NE and the upper surface 100 of the substrate 10 changes, the height difference between the edge of the upper surface 100 and the proximal axis CP when the substrate 10 undergoes thermal expansion also varies. For example, as shown in Table 3 below, when the distance DS between all electrodes PE, NE and the upper surface 100 is designed to be 0.4 mm, 0.5 mm or 0.6 mm, the height difference between the edge of the upper surface 100 and the near-axis CP of the electrostatic chuck 1c in a high-temperature process environment of 1000°C is approximately 44.94 μm, 45.76 μm and 45.64 μm respectively (all of which are smaller than the maximum height difference of 54.91 μm produced by the thermal expansion of the existing electrostatic chuck at the same temperature).

表三 Table 3 電極與上表面之間的距離 Distance between electrode and top surface 上表面的邊緣與近軸處的高度差異 Height difference between the edge of the upper surface and the proximal axis 0.6 mm 0.6 mm 45.64 μm 45.64 μm 0.5 mm 0.5 mm 45.76 μm 45.76 μm 0.4 mm 0.4 mm 44.94 μm 44.94 μm

由圖9和圖10可見，電極PE、NE的結構圖案和形成於上表面100的溝槽102的結構圖案為相互匹配，且電極PE、NE與溝槽102在基板的中心軸CL的方向上彼此不重疊，使得電極PE、NE可更貼近上表面100，以縮短電極PE、NE與放置於上表面100的晶圓(未繪示)之間的距離。As can be seen from Figures 9 and 10, the structural patterns of the electrodes PE and NE match the structural patterns of the grooves 102 formed on the upper surface 100, and the electrodes PE and NE and the grooves 102 do not overlap with each other in the direction of the center axis CL of the substrate, so that the electrodes PE and NE can be closer to the upper surface 100 to shorten the distance between the electrodes PE and NE and the wafer (not shown) placed on the upper surface 100.

如圖10所示，在不同區域RR中被溝槽102所分隔開的相鄰兩正電極PE透過連接片110彼此電性連接。同樣地，在不同區域RR中被溝槽102所分隔開的相鄰兩負電極NE亦透過連接片110彼此電性連接。10 , two adjacent positive electrodes PE separated by the trench 102 in different regions RR are electrically connected to each other through the connecting sheet 110 . Similarly, two adjacent negative electrodes NE separated by the trench 102 in different regions RR are also electrically connected to each other through the connecting sheet 110 .

在本實施例中，電極PE、NE與上表面100之間的距離為0.5 mm。另外，在同時包含負電極NE和正電極PE的區域RR中，負電極NE的曲線部和正電極PE的曲線部在徑向上交錯排列設置，且負電極NE和正電極PE相鄰的曲線部之間的距離為1.0 mm。並且，在相鄰的兩個區域RR中，被溝槽102所間隔開的相鄰電極PE、NE之間的距離為2.0 mm。如此，當上表面100為6吋盤面時，電極PE、NE佈設總面積為141.3 cm ²。在這樣的配置下，並假設上表面100與晶圓之間的間隙為0.01 mm，當操作電壓為2,000伏特時，靜電吸盤1c所產生的靜電吸力為571.14 Pa。 In this embodiment, the distance between the electrodes PE, NE and the upper surface 100 is 0.5 mm. In addition, in the region RR including both the negative electrode NE and the positive electrode PE, the curved portion of the negative electrode NE and the curved portion of the positive electrode PE are arranged alternately in the radial direction, and the distance between the adjacent curved portions of the negative electrode NE and the positive electrode PE is 1.0 mm. Moreover, in the two adjacent regions RR, the distance between the adjacent electrodes PE, NE separated by the groove 102 is 2.0 mm. Thus, when the upper surface 100 is a 6-inch disk, the total area of the electrodes PE, NE is 141.3 ^cm2 . Under such a configuration, and assuming that the gap between the upper surface 100 and the wafer is 0.01 mm, when the operating voltage is 2,000 volts, the electrostatic suction force generated by the electrostatic chuck 1c is 571.14 Pa.

相較下，舉一現有技術之靜電吸盤為例，其電極與溝槽在中心軸的方向上係重疊設置，從而電極與上表面之間的距離為0.78 mm，且所述現有技術之靜電吸盤中相鄰電極之間的距離皆為2.0 mm或以上，從而在上表面為6吋盤面時，電極佈設總面積僅為123.6 cm ²。在這樣的配置下，並假設上表面與晶圓之間的間隙亦為0.01 mm，當操作電壓為2,000伏特時，所述現有技術之靜電吸盤所產生的靜電吸力僅為229.57 Pa。 In contrast, in the case of an electrostatic chuck of the prior art, the electrodes and the grooves are overlapped in the direction of the central axis, so that the distance between the electrodes and the upper surface is 0.78 mm, and the distance between adjacent electrodes in the electrostatic chuck of the prior art is 2.0 mm or more, so that when the upper surface is a 6-inch disk, the total area of the electrode layout is only 123.6 cm ^2. Under such a configuration, and assuming that the gap between the upper surface and the wafer is also 0.01 mm, when the operating voltage is 2,000 volts, the electrostatic suction force generated by the electrostatic chuck of the prior art is only 229.57 Pa.

由上述可知，相較於現有技術之靜電吸盤，本實施例之靜電吸盤1c縮短了電極與上表面之間的距離，並增加了電極佈設總面積，從而在相同的操作電壓下，靜電吸盤1c可產生較大的靜電吸力。進一步地，當對本實施例之靜電吸盤1c改為施加1,500伏特的操作電壓時，靜電吸盤1c所產生的靜電吸力為321.34 Pa，其仍然大於現有技術之靜電吸盤在操作電壓為2,000伏特時所產生的靜電吸力(229.57 Pa)。於此，相較於現有技術之靜電吸盤，本實施例之靜電吸盤1c可降低操作電壓，而仍有足夠的靜電吸力以固定吸附晶圓(未繪示)。As can be seen from the above, compared with the electrostatic suction cup of the prior art, the electrostatic suction cup 1c of the present embodiment shortens the distance between the electrode and the upper surface and increases the total area of the electrode layout, so that under the same operating voltage, the electrostatic suction cup 1c can generate a larger electrostatic suction force. Furthermore, when the electrostatic suction cup 1c of the present embodiment is changed to apply an operating voltage of 1,500 volts, the electrostatic suction force generated by the electrostatic suction cup 1c is 321.34 Pa, which is still greater than the electrostatic suction force (229.57 Pa) generated by the electrostatic suction cup of the prior art when the operating voltage is 2,000 volts. Here, compared with the electrostatic chuck of the prior art, the electrostatic chuck 1c of the present embodiment can reduce the operating voltage, while still having sufficient electrostatic suction force to fix and adsorb the wafer (not shown).

根據上述實施例之靜電吸盤，其電極分別位於溝槽所分隔出的區域中，從而電極的結構圖案和溝槽的結構圖案為相互匹配，此外，電極與溝槽在基板的中心軸的方向上彼此不重疊，且電極與上表面之間的距離小於溝槽在上表面上凹陷的深度，使得電極可更貼近基板的上表面，以縮短電極與放置於上表面的晶圓(未繪示)之間的距離。藉此，縮短電極與基板的上表面之間的距離，可在不增加操作電壓的情況下增加靜電吸力強度，進而有利於節能減排的目標。According to the electrostatic chuck of the above embodiment, the electrodes are respectively located in the areas separated by the grooves, so that the structural patterns of the electrodes and the structural patterns of the grooves are matched with each other. In addition, the electrodes and the grooves do not overlap each other in the direction of the central axis of the substrate, and the distance between the electrodes and the upper surface is less than the depth of the grooves on the upper surface, so that the electrodes can be closer to the upper surface of the substrate to shorten the distance between the electrodes and the wafer (not shown) placed on the upper surface. In this way, by shortening the distance between the electrodes and the upper surface of the substrate, the electrostatic suction strength can be increased without increasing the operating voltage, which is beneficial to the goal of energy saving and emission reduction.

在部分實施態樣中，基板的上表面除了開設有多個線型溝槽之外，還開設有多個同心圓溝槽，以將基板的上表面進一步分隔成多個區域，從而減小每個區域各自的面積，進而可降低上表面因高溫產生的翹曲。In some implementations, in addition to a plurality of linear grooves, a plurality of concentric circular grooves are formed on the upper surface of the substrate to further divide the upper surface of the substrate into a plurality of regions, thereby reducing the area of each region and further reducing the warp of the upper surface caused by high temperature.

雖然本發明以前述之較佳實施例揭露如上，然其並非用以限定本發明，任何熟習相像技藝者，在不脫離本發明之精神和範圍內，當可作些許之更動與潤飾，因此本發明之專利保護範圍須視本說明書所附之申請專利範圍所界定者為準。Although the present invention is disclosed as above with the aforementioned preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of patent protection of the present invention shall be subject to the scope of the patent application attached to this specification.

1,1b,1c:靜電吸盤 10:基板 P1:上基板 P2:下基板 100:上表面 101:下表面 102:溝槽 CG:同心圓溝槽 SG:線型溝槽 RR:區域 CP:軸心 CL:中心軸 11:電極層 PE,NE:電極 110:連接片 12:基座 DS:距離 DP:深度 D1:電極距離 D2:間距 1,1b,1c: electrostatic chuck 10: substrate P1: upper substrate P2: lower substrate 100: upper surface 101: lower surface 102: groove CG: concentric groove SG: linear groove RR: region CP: axis CL: center axis 11: electrode layer PE,NE: electrode 110: connector 12: base DS: distance DP: depth D1: electrode distance D2: spacing

圖1為根據本發明之第一實施例所述之靜電吸盤的立體示意圖。圖2為圖1之靜電吸盤的分解示意圖。圖3為圖1之靜電吸盤的上視圖。圖4為圖2之靜電吸盤的電極層的電極的上視圖。圖5為根據本發明之第一實施例所述之靜電吸盤的局部剖面示意圖。圖6為根據本發明之第二實施例所述之靜電吸盤的上視圖。圖7為圖6之靜電吸盤的電極層的電極的上視圖。圖8為根據本發明之第二實施例所述之靜電吸盤的局部剖面示意圖。圖9為根據本發明之第三實施例所述之靜電吸盤的上視圖。圖10為圖9之靜電吸盤的電極層的上視圖。 FIG. 1 is a three-dimensional schematic diagram of an electrostatic suction cup according to the first embodiment of the present invention. FIG. 2 is a schematic diagram of an exploded view of the electrostatic suction cup of FIG. 1. FIG. 3 is a top view of the electrostatic suction cup of FIG. 1. FIG. 4 is a top view of the electrode of the electrode layer of the electrostatic suction cup of FIG. 2. FIG. 5 is a partial cross-sectional schematic diagram of the electrostatic suction cup according to the first embodiment of the present invention. FIG. 6 is a top view of the electrostatic suction cup according to the second embodiment of the present invention. FIG. 7 is a top view of the electrode of the electrode layer of the electrostatic suction cup of FIG. 6. FIG. 8 is a partial cross-sectional schematic diagram of the electrostatic suction cup according to the second embodiment of the present invention. FIG. 9 is a top view of the electrostatic chuck according to the third embodiment of the present invention. FIG. 10 is a top view of the electrode layer of the electrostatic chuck of FIG. 9 .

1:靜電吸盤 1: Electrostatic suction cup

10:基板 10: Substrate

P1:上基板 P1: Upper substrate

P2:下基板 P2: Lower substrate

100:上表面 100: Upper surface

101:下表面 101: Lower surface

102:溝槽 102: Groove

CL:中心軸 CL: Center axis

11:電極層 11: Electrode layer

12:基座 12: Base

Claims

一種靜電吸盤，包含：一基板，具有一上表面、一下表面以及複數個溝槽，該上表面相對於該下表面，且該複數個溝槽形成於該上表面並分隔出複數個區域；一電極層，埋設於該基板中，該電極層包含複數個電極，該複數個電極分別位於該複數個區域中，且該複數個電極與該上表面之間定義的一距離小於該複數個溝槽在該上表面上凹陷的一深度；以及一基座，連接於該基板的該下表面，以承載並固定該基板；其中，該電極層更包含複數個連接片，且該複數個連接片分別跨設於該複數個溝槽，以連接相鄰兩區域中具有相同極性的兩個該複數個電極。 An electrostatic chuck includes: a substrate having an upper surface, a lower surface and a plurality of grooves, the upper surface is opposite to the lower surface, and the plurality of grooves are formed on the upper surface and separate a plurality of regions; an electrode layer is buried in the substrate, the electrode layer includes a plurality of electrodes, the plurality of electrodes are respectively located in the plurality of regions, and the plurality of electrodes are connected to the upper surface. A distance defined between the surfaces is less than a depth of the plurality of grooves recessed on the upper surface; and a base connected to the lower surface of the substrate to support and fix the substrate; wherein the electrode layer further comprises a plurality of connecting pieces, and the plurality of connecting pieces are respectively arranged across the plurality of grooves to connect two of the plurality of electrodes with the same polarity in two adjacent regions.

如請求項1所述之靜電吸盤，其中該複數個電極與該上表面之間的該距離大於等於0.1公釐且小於等於0.7公釐。 An electrostatic chuck as described in claim 1, wherein the distance between the plurality of electrodes and the upper surface is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

如請求項1所述之靜電吸盤，其中該基板為氮化鋁陶瓷基板，該基座為鋁基座，且該電極層的材質為鎢合金。 The electrostatic chuck as described in claim 1, wherein the substrate is an aluminum nitride ceramic substrate, the base is an aluminum base, and the material of the electrode layer is a tungsten alloy.

如請求項3所述之靜電吸盤，其中該鎢合金包含45~65wt%的鎢粉、15~35wt%之不同於鎢的金屬及金屬氧化物以及20wt%或以上的黏結劑。 An electrostatic chuck as described in claim 3, wherein the tungsten alloy comprises 45-65wt% of tungsten powder, 15-35wt% of metals and metal oxides other than tungsten, and 20wt% or more of a binder.

如請求項1所述之靜電吸盤，其中該靜電吸盤為圓盤狀，該複數個溝槽係為複數個同心圓溝槽以及複數個線型溝槽，且該複數個同心圓溝槽與該複數個線型溝槽交錯設置並分隔出該複數個區域。 The electrostatic suction cup as described in claim 1, wherein the electrostatic suction cup is in the shape of a disk, the plurality of grooves are a plurality of concentric circular grooves and a plurality of linear grooves, and the plurality of concentric circular grooves and the plurality of linear grooves are arranged alternately and separate the plurality of regions.

如請求項5所述之靜電吸盤，其中該基板更包含一軸心，位於該軸心處的其中一該複數個區域係由其中一該複數個同心圓溝槽所圍繞成的一圓形區域，且該複數個線型溝槽從該圓形區域的周緣以輻射狀朝該上表面的邊緣線性延伸。 The electrostatic chuck as described in claim 5, wherein the substrate further comprises an axis, and one of the plurality of regions located at the axis is a circular region surrounded by one of the plurality of concentric circular grooves, and the plurality of linear grooves extend linearly from the periphery of the circular region in a radial shape toward the edge of the upper surface.

如請求項1所述之靜電吸盤，其中該複數個電極係為複數個正電極以及複數個負電極，且該複數個區域中各自對應設有其中一該複數個正電極或其中一該複數個負電極。 An electrostatic suction cup as described in claim 1, wherein the plurality of electrodes are a plurality of positive electrodes and a plurality of negative electrodes, and each of the plurality of regions is provided with one of the plurality of positive electrodes or one of the plurality of negative electrodes.

如請求項1所述之靜電吸盤，其中該複數個電極係為複數個正電極以及複數個負電極，且至少一該複數個區域中對應設有至少一該複數個正電極與至少一該複數個負電極。 An electrostatic suction cup as described in claim 1, wherein the plurality of electrodes are a plurality of positive electrodes and a plurality of negative electrodes, and at least one of the plurality of regions is provided with at least one of the plurality of positive electrodes and at least one of the plurality of negative electrodes.

如請求項8所述之靜電吸盤，其中在該至少一該複數個區域中，相鄰的兩個該複數個電極之間定義的一電極距離大於等於1.0公釐且小於等於1.2公釐。 An electrostatic chuck as described in claim 8, wherein in at least one of the plurality of regions, an electrode distance defined between two adjacent plurality of electrodes is greater than or equal to 1.0 mm and less than or equal to 1.2 mm.

如請求項7或請求項8所述之靜電吸盤，其中該複數個正電極與該複數個負電極交錯排列設置。 An electrostatic chuck as described in claim 7 or claim 8, wherein the plurality of positive electrodes and the plurality of negative electrodes are arranged in an alternating manner.