200941621 六、發明說明： 【發明所屬之技術領域】 本發明是有關用以對半導體晶圓等的被處理體進行成 膜處理等的熱處理的處理裝置、被使用於該處理裝置的載 置台裝置及溫度控制方法。 【先前技術】 φ 一般’爲了製造半導體積體電路，是對半導體晶圓等 的被處理體重複進行成膜處理、蝕刻處理、熱擴散處理、 改質處理等各種的處理。 例如若舉例說明對半導體晶圓每一片實施熱處理的單 片式的處理裝置，則在可抽真空的處理容器内，將內藏例 如由鉬線所構成的電阻加熱式加熱器的載置台安裝設於從 容器底部立起的脚部的上端，在此載置台上載置半導體晶 圓。然後，在如此將半導體晶圓載置於載置台上的狀態下 〇 ，一面在處理容器内流動預定的處理氣體一面將其中維持 於預定的減壓環境，同時驅動電阻加熱式加熱器，而將半 導體晶圓加熱維持於預定的溫度，實施成膜處理等的預定 處理。 上述載置台或予以支撐的脚部是從以往起一般主要使 用銘合金，如周知般，半導體晶圓是非常討厭各種的金屬 汚染，因此提案使用金屬汚染的程度比上述鋁合金更少， 且耐熱性亦佳之例如A1N那樣的陶瓷材作爲載置台或脚部 (例如實開平3-128668號公報、特開平6-252055號公報 200941621 在該等專利文獻中，是在載置台的背面中央部連接1 根中空狀的脚部，可在該中空狀的脚部内收容對電阻加熱 式加熱器的給電線等必要的配線類。而且，在上述載置台 的中心部的下面側設置熱電偶的同時，將載置台的電阻加 熱式加熱器予以同心狀地分割成複數、例如2個，藉此設 置可彼此獨立控制的同心狀的2個加熱區域，可根據設於 載置台的中心部的上述熱電偶的測定値來個別控制上述各 @ 加熱區域的溫度。 具體而言，例如若舉成膜處理爲例，則依加熱半導體 晶圓的製程溫度，膜厚的面内均一性形成最佳的溫度分布 會有所不同，因此在處理製品晶圓之前，預先求取依製程 溫度之成爲最適的溫度分布的各加熱器間的電流比或電壓 比，然後，在處理實際的製品晶圓時，有關最内周的加熱 區域的溫度是根據上述熱電偶的測定値來進行反餽控制， 有關除此以外的外側的加熱區域的溫度是根據使對應於製 ◎ 程溫度而事先求取之對最内周加熱區域的加熱器之電流比 或電壓比來供給電力’藉此進行所謂的開迴路控制。 可是’如上述般載置台或予以支撐的脚部是例如由 A 1N (氮化鋁）等的陶瓷材所構成，但此陶瓷材爲脆性材 料’有時會因載置台的内外周間的溫度分布所引起發生的 熱應力，造成此載置台容易破損。特別是以依製程溫度的 電流比或電壓比來控制載置台的内外周的加熱區域（加熱 器）的溫度之方法’會有陶瓷製的載置台等容易破損的問 -6- 200941621 題。 【發明內容】 本發明的目的是在於提供一種將被處理體載置於載置 台上來加熱時，難因熱應力而破損的載置台裝置及搭載如 此的載置台裝置之處理裝置。 本發明的其他目的是在於提供一種將被處理體載置於 〇 載置台上來加熱時，載置台難因熱應力而破損的溫度控制 方法。 本發明的另外其他的目的是在於提供一種記憶用以實 行如此的溫度控制方法的程式之記憶媒體。 本發明者等針對由陶瓷材所構成的載置台的破損來深 入硏究的結果，發現與利用電流比或電壓比的溫度控制作 比較，利用電力比的溫度控制的情況，較可壓低成爲破損 的原因之内外周間的溫度差，達成本發明。 ® 亦即，若根據本發明的第1觀點，則可提供一種載置 台裝置，其特徵係具備： 載置台，其係用以載置被處理體； 加熱機構’其係具有複數的加熱器部，該複數的加熱 器部係設於同心狀區劃於上述載置台的複數的各加熱區域 * 脚部’其係被連接至上述載置台的中心部，水平支撐 上述載置台； 溫度測定部’其係使對應於上述複數的加熱區域内的 -7- 200941621 最内周的加熱區域來設置；及 電源控制部，其係根據上述溫度測定部的測定値來反 餽控制上述最内周的加熱器部的溫度，且以對上述最内周 的加熱器部之安全供給電力比來控制往上述其他加熱器部 的供給電力，該對上述最内周的加熱器部之安全供給電力 比係以上述加熱區域間的溫度差能夠形成上述載置台不會 破損的範圍之方式決定。 如此，在控制載置被處理體的載置台的溫度時，可根 0 據溫度測定部的測定値來反餽控制上述最内周的加熱器部 的溫度，且以對最内周的加熱器部之電力比（安全供給電 力比）來控制往其他加熱器部的供給電力，該對最内周的 加熱器部之電力比（安全供給電力比）是以載置台的各 加熱區域（加熱器）的溫度差能夠形成載置台不會破損的 範圍之方式決定，藉此可抑制在載置台的内外周間發生的 溫度差，防止載置台因爲應力而破損。 此情況，上述安全供給電力比，可以上述載置台的最 d 内周的加熱區域的溫度能夠形成最低的方式設定，具體而 言，上述安全供給電力比，係上述載置台爲對應於直徑 3 0 0mm的被處理體者時，可設定成上述最内周與最外周的 加熱區域間的溫度差爲形成3 3 °C以内的電力比。 並且，在上述載置台的昇溫時及降溫時，上述電源控 制部係於上述載置台的昇溫時及降溫時，以最内周的加熱 區域的溫度比最外周的加熱區域的溫度不會低於預定的溫 度差以上的方式控制。 -8 - 200941621 而且，較理想是上述電源控制部係於上述載置台的昇 溫時以最内周的加熱區域的溫度要比最外周高的狀態昇溫 ，若到達設定溫度，則控制往上述各加熱器部的供給電力 ，使能夠依序接近上述安全供給電力比。 又，上述溫度測定部，典型的可使用具有熱電偶者》 又，上述載置台及上述脚部的至少一方，可使用由陶 瓷材所構成者。 φ 若根據本發明的第2觀點，則可提供一種處理裝置， 係對被處理體實施預定的熱處理之處理裝置，係特徵係具 備· 處理容器，其係内部環境可排氣； 氣體供給機構，其係往上述處理容器内供給必要的氣 體；及 載置台裝置，其係載置被處理體， 上述載置台裝置係具有： Φ 載置台’其係用以載置被處理體； 加熱機構，其係具有複數的加熱器部，該複數的加熱 器部係設於同心狀區劃形成於上述載置台的複數的各加熱 區域； 脚部’其係被連接至上述載置台的中心部，水平支撐 上述載置台； 溫度測定部，其係使對應於上述複數的加熱區域内的 最内周的加熱區域來設置；及 電源控制部’其係根據上述溫度測定部的測定値來反 -9- 200941621 餽控制上述最内周的加熱器部的溫度’且以對上述最内周 的加熱器部之安全供給電力比來控制往上述其他加熱器部 的供給電力，該對上述最内周的加熱器部之安全供給電力 比係以上述加熱區域間的溫度差能夠形成上述載置台不會 破損的範圍之方式決定。 若根據本發明的第3觀點，則可提供一種溫度控制方 法，其係於内部環境可排氣的處理容器内所被設置的載置 台上載置被處理體，控制加熱機構來進行上述被處理體的 Q 溫度控制之方法，該加熱機構係具有複數的加熱器部，該 複數的加熱器部係設於同心狀區劃形成於上述載置台的複 數的各加熱區域，其特徵爲： 測定上述複數的加熱區域内的最内周的加熱區域的溫 度， 以能夠根據上述所被測定的溫度來反餽控制上述最内 周的加熱加熱器部而形成設定溫度之方式控制，及 以對上述最内周的加熱器部之安全供給電力比來控制 © 往上述其他加熱器部的供給電力，該對上述最内周的加熱 器部之安全供給電力比係以上述加熱區域間的溫度差能夠 形成上述載置台不會破損的範圍之方式決定。 在上述第3觀點中，在上述載置台的昇溫時，較理想 是維持成最内周的加熱區域的溫度比最外周的加熱區域的 溫度不會低於預定的溫度差以上。 並且，在上述載置台的降溫時，較理想是維持成最内 周的加熱區域的溫度比最外周的加熱區域的溫度不會低於 -10- 200941621 預定的溫度差以上。 若根據本發明的第4觀點，則可提供一種記憶媒體， 其係記億有以能夠進行溫度控制方法的方式來使處理裝置 控制於電腦的程式，該溫度控制方法係於内部環境可排氣 的處理容器内所被設置的載置台上載置被處理體，控制加 熱機構來進行上述被處理體的溫度控制，該加熱機構係具 有複數的加熱器部，該複數的加熱器部係設於同心狀區劃 0 形成於上述載置台的複數的各加熱區域，而對被處理體實 施預定的處理時包含： 測定上述複數的加熱區域内的最内周的加熱區域的溫 度， 以能夠根據上述所被測定的溫度來反餽控制上述最内 周的加熱加熱器部而形成設定溫度之方式控制，及 以對上述最内周的加熱器部之安全供給電力比來控制 往上述其他加熱器部的供給電力，該對上述最内周的加熱 〇 器部之安全供給電力比係以上述加熱區域間的溫度差能夠 形成上述載置台不會破損的範圍之方式決定。 【實施方式】 以下，參照圖面來說明有關本發明的實施形態。 圖1式表示本發明之一實施形態的處理裝置的槪略剖 面圖，圖2是表示在處理裝置所具備的載置台裝置的載置 台設置的加熱機構的平面圖。另外，在此是舉例說明藉由 CVD來對被處理體的半導體晶圓進行成膜處理時。 -11 - 200941621 如圖示，此處理裝置2是具有例如藉由鎳、鎳合金、 或鋁合金來形成圓筒體狀的處理容器4。在此處理容器4 的頂部設置下面具有多數的氣體噴出孔6A、6B之淋浴頭 部6作爲氣體供給機構，藉此可將處理氣體例如成膜氣體 導入至處理容器4内的處理空間S。此淋浴頭部6内是被 分離區劃成例如2個的氣體空間8A、8B，且在各氣體空 間8A、8B分別連通上述各氣體噴出孔6A、6B，在處理空 間S兩種氣體初次取得混合，形成所謂的後混合型。 此淋浴頭部6的全體是例如藉由鎳、鎳合金、鋁合金 等所形成。具有此淋浴頭部6的處理容器4的頂部是在處 理容器4的側壁上端例如經由〇型環的密封構件1 〇來安 裝’可維持處理容器4内的氣密性。 而且，在此處理容器4的側壁形成有用以搬出入被處 理體的半導體晶圓W的搬出入口 12，在此設有閘閥14而 可開閉。此閘閥14是連接未圖示的裝載鎖定室或轉移窒 室。 並且’在此處理容器4的底部16的中央部側形成有 向下方向凹陷的凹狀部17，該凹狀部17的内部是形成排 氣空間18。而且，在規定此排氣空間18的凹狀部17的下 部側壁設有排氣口 20。此排氣口 20是連接途中設有未圖 示的壓力控制閥或真空泵的真空排氣系22，可藉由此真空 排氣系22來將處理容器4内抽真空，維持於預定的壓力 〇 在處理容器4内設有用以載置被處理體的半導體晶圓 -12- 200941621 的載置台裝置24。此載置台裝置24是具有：在其上面實 際載置晶圓W的載置台26、及連接至該載置台26下面的 中心部往下方延伸水平支撐載置台26的脚部28。脚部28 是其下端被規定排氣空間18的凹狀部17的底部16A所支 撐。脚部28是内部爲中空狀、亦即圓筒體狀，下端被開 放。載置台26與脚部28皆是例如以A1N等的陶瓷材所形 成。另外，亦可該等的一方爲以陶瓷材所形成。 φ 在載置台26的上部側埋設有電阻加熱式加熱器30， 作爲用以加熱被載置於此的晶圓W之加熱機構。此電阻 加熱式加熱器3 0是例如由鉬線所構成，如圖2所示，此 電阻加熱式加熱器3 0是在此被同心狀地分割成内側區域 加熱器32A及外側區域加熱器32B，形成内側加熱區域及 外側加熱區域的2個加熱區域，可在每個區域控制加熱溫 度。然後，以由陶瓷材所構成的載置台26及電阻加熱式 加熱器3 0來構成陶瓷加熱器。 〇 另外，此區域數並無特別加以限定，亦可爲3區域以 上。[Technical Field] The present invention relates to a processing apparatus for performing heat treatment such as a film forming process on a semiconductor wafer or the like, a mounting table apparatus used in the processing apparatus, and Temperature control method. [Prior Art] φ In general, in order to manufacture a semiconductor integrated circuit, various processes such as a film formation process, an etching process, a thermal diffusion process, and a reforming process are repeated on a semiconductor wafer or the like. For example, a single-piece processing apparatus that heat-treats each piece of a semiconductor wafer is exemplified, and a mounting table of a resistance-heating heater including, for example, a molybdenum wire is installed in a vacuum-processable processing container. A semiconductor wafer is placed on the mounting table at the upper end of the leg rising from the bottom of the container. Then, while the semiconductor wafer is placed on the mounting table in this manner, the predetermined processing gas is flowed through the processing container while maintaining the predetermined decompression environment while driving the resistance heating heater to drive the semiconductor. The wafer heating is maintained at a predetermined temperature, and a predetermined process such as a film forming process is performed. The above-mentioned mounting table or the supporting leg is generally used mainly from the past. As is well known, semiconductor wafers are very annoying to various metal contaminations, and therefore it is proposed to use metal contamination to a lesser extent than the above-mentioned aluminum alloy, and heat resistant. For example, the ceramic material such as the A1N is used as the mounting table or the leg portion. For example, in the patent documents, the center portion of the back surface of the mounting table is connected to the center of the mounting table. In the hollow leg portion, a wiring such as a feed wire for the resistance heating heater can be housed in the hollow leg portion, and a thermocouple is provided on the lower surface side of the center portion of the mounting table. The resistance heating heater of the mounting table is concentrically divided into a plurality of, for example, two, thereby providing two concentric heating regions that can be independently controlled from each other, and can be based on the thermocouples provided at the center portion of the mounting table. The temperature of each of the above-mentioned heating regions is individually controlled by measurement. Specifically, for example, if the film formation process is taken as an example, the process of heating the semiconductor wafer is performed. The optimum temperature distribution of the in-plane uniformity of the film thickness will be different. Therefore, before processing the product wafer, the current ratio or voltage between the heaters which is the optimum temperature distribution according to the process temperature is obtained in advance. Then, when the actual product wafer is processed, the temperature of the innermost heating zone is feedback-controlled according to the measurement of the thermocouple, and the temperature of the outer heating zone is based on The electric current is supplied to the current ratio or the voltage ratio of the heater in the innermost heating zone in advance, and the so-called open circuit control is performed. However, the foot is placed or supported as described above. The portion is made of, for example, a ceramic material such as A 1N (aluminum nitride). However, the ceramic material is a brittle material. The thermal stress generated by the temperature distribution between the inner and outer circumferences of the mounting table may cause the mounting table. It is easy to break. In particular, the method of controlling the temperature of the heating zone (heater) of the inner and outer circumference of the mounting table by the current ratio or voltage ratio according to the process temperature [Embodiment] The object of the present invention is to provide a mounting table device that is difficult to be damaged by thermal stress when the object to be processed is placed on a mounting table and heated. A processing apparatus equipped with such a mounting table device. Another object of the present invention is to provide a temperature control method in which a mounting table is hard to be damaged by thermal stress when the object to be processed is placed on a crucible mounting table for heating. Another object of the present invention is to provide a memory medium for storing a program for performing such a temperature control method. The inventors of the present invention have intensively studied the damage of a mounting table made of a ceramic material, and found a ratio with the utilization current or In comparison with the temperature control of the voltage ratio, the temperature difference between the inner and outer circumferences which is the cause of the damage is reduced by the temperature control of the electric power ratio, and the present invention has been attained. In the first aspect of the present invention, according to the first aspect of the present invention, there is provided a mounting table device comprising: a mounting table for placing a target object; and a heating mechanism having a plurality of heater portions The plurality of heater portions are disposed in a plurality of heating regions* concentrically arranged on the mounting table. The leg portions are connected to the center portion of the mounting table to horizontally support the mounting table. The temperature measuring portion Providing a heating zone corresponding to the innermost circumference of -7-200941621 in the heating zone of the plural number; and a power supply control unit that feedback-controls the heater section of the innermost circumference based on the measurement 値 of the temperature measuring unit The temperature is supplied to the other heater unit in a ratio of the safe supply power to the innermost peripheral heater unit, and the ratio of the safe supply power to the innermost heater unit is the above-described heating. The temperature difference between the regions can be determined in such a manner that the above-described mounting table does not break. As described above, when controlling the temperature of the mounting table on which the object to be processed is placed, the temperature of the heater portion of the innermost circumference can be feedback-controlled based on the measurement 値 of the temperature measuring unit, and the heater portion of the innermost circumference can be controlled. The power ratio (safety supply power ratio) is used to control the supply power to the other heater units, and the power ratio (safety supply ratio) of the pair of innermost heater units is the heating area (heater) of the mounting table. The temperature difference can be determined in such a manner that the mounting table does not break, and the temperature difference occurring between the inner and outer circumferences of the mounting table can be suppressed, and the mounting table can be prevented from being damaged by stress. In this case, the safety supply power ratio may be set such that the temperature of the heating zone of the most d inner circumference of the mounting table can be minimized. Specifically, the safety supply power ratio is such that the mounting table corresponds to a diameter of 30. In the case of a 0 mm object to be processed, the temperature difference between the heating zone of the innermost circumference and the outermost circumference may be set to a ratio of electric power within 33 ° C. Further, during the temperature rise and the temperature drop of the mounting table, the power supply control unit is configured such that the temperature of the innermost heating zone is lower than the temperature of the outermost heating zone when the temperature is raised and lowered during the mounting stage. Controlled by a predetermined temperature difference or more. -8 - 200941621 Further, it is preferable that the power source control unit is configured to increase the temperature of the innermost heating zone in a state where the temperature of the innermost circumference is higher than the outermost circumference when the temperature is raised by the mounting table, and to control the heating when the set temperature is reached. The power supplied to the unit is such that the safety supply ratio can be sequentially approached. Further, in the above-described temperature measuring unit, at least one of the mounting table and the leg portion can be used as the thermocouple, and a ceramic material can be used. According to a second aspect of the present invention, there is provided a processing apparatus which is a processing apparatus for performing a predetermined heat treatment on a target object, and is characterized in that: a processing container is provided, and an internal environment is exhausted; and a gas supply mechanism is provided; And supplying a required gas to the processing container; and the mounting table device for placing the object to be processed, wherein the mounting table device has: Φ a mounting table for mounting the object to be processed; and a heating mechanism A plurality of heater portions are provided in a plurality of heating regions that are concentrically formed on the mounting table; the leg portions are connected to the center portion of the mounting table to horizontally support the above a mounting stage; a temperature measuring unit that is provided corresponding to the innermost heating area in the plurality of heating regions; and a power supply control unit that is based on the measurement of the temperature measuring unit -9-200941621 Controlling the temperature of the heater portion of the innermost circumference and controlling the ratio of the safe supply power to the heater portion of the innermost circumference to control the other heater unit Power is supplied, the ratio of the power supplied to the heater portion of the safety system of the inner most circumference to the temperature difference between the heating region can be formed in the mounting table unbreakable decided range. According to a third aspect of the present invention, a temperature control method is provided in which a target object is placed on a mounting table provided in a processing container capable of exhausting an internal environment, and the heating mechanism is controlled to perform the processed object. In the Q temperature control method, the heating mechanism has a plurality of heater portions, and the plurality of heater portions are disposed in a plurality of heating regions that are concentrically formed on the mounting table, and are characterized in that: The temperature of the innermost heating zone in the heating zone is controlled so as to feedback control the temperature of the innermost circumference of the heating heater section to form a set temperature, and to the innermost circumference The safe supply power ratio of the heater unit controls the supply power to the other heater unit, and the safety supply power ratio to the innermost heater unit is such that the temperature difference between the heating regions can form the mounting table. It is determined in a way that does not damage the scope. In the third aspect, it is preferable that the temperature of the heating zone that is maintained at the innermost circumference is not lower than a predetermined temperature difference or more than the temperature of the outermost heating zone when the temperature of the mounting table is raised. Further, in the case of lowering the temperature of the mounting table, it is preferable that the temperature of the heating zone which is maintained at the innermost circumference is not lower than the temperature of the predetermined temperature difference of the outermost circumference of the heating zone. According to the fourth aspect of the present invention, it is possible to provide a memory medium which is a program for controlling a processing device to a computer in a manner capable of performing a temperature control method, the temperature control method being exhausted in an internal environment The processing unit provided in the processing container mounts the object to be processed, and controls the heating mechanism to control the temperature of the object to be processed. The heating mechanism has a plurality of heater units, and the plurality of heater units are disposed at the same The region 0 is formed in each of the plurality of heating regions of the mounting table, and when the predetermined processing is performed on the object to be processed, the temperature of the innermost heating region in the plurality of heating regions is measured to be able to be The measured temperature is feedback-controlled to control the heating heater portion of the innermost circumference to form a set temperature, and the power supply to the other heater unit is controlled by a ratio of the safely supplied electric power to the innermost peripheral heater unit. The ratio of the safe supply power to the innermost heating section of the inner circumference can be shaped by the temperature difference between the heating zones It is determined in such a manner that the above-mentioned mounting table does not break. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic cross-sectional view showing a processing apparatus according to an embodiment of the present invention, and Fig. 2 is a plan view showing a heating mechanism provided in a mounting table of the mounting table apparatus included in the processing apparatus. Here, the case where the semiconductor wafer of the object to be processed is subjected to a film formation process by CVD is exemplified. -11 - 200941621 As shown, the processing apparatus 2 is a processing container 4 having a cylindrical shape formed of, for example, nickel, a nickel alloy, or an aluminum alloy. A shower head portion 6 having a plurality of gas ejection holes 6A, 6B below is provided at the top of the processing container 4 as a gas supply means, whereby a processing gas such as a film forming gas can be introduced into the processing space S in the processing container 4. In the shower head portion 6, the gas spaces 8A and 8B are divided into two, for example, two gas spaces 8A and 8B, and the respective gas ejection holes 6A and 6B are respectively connected to the respective gas spaces 8A and 8B, and the two gases are first mixed in the processing space S. Formed a so-called post-mixing type. The entire shower head portion 6 is formed of, for example, nickel, a nickel alloy, an aluminum alloy or the like. The top of the processing container 4 having the shower head 6 is installed at the upper end of the side wall of the processing container 4, for example, via the sealing member 1 〇 of the 〇-ring, and the airtightness in the processing container 4 can be maintained. Further, a side wall of the processing container 4 is formed with a carry-out port 12 for carrying in and out of the semiconductor wafer W of the object to be processed, and a gate valve 14 is provided to be opened and closed. This gate valve 14 is connected to a load lock chamber or a transfer chamber (not shown). Further, a concave portion 17 recessed in the downward direction is formed on the central portion side of the bottom portion 16 of the processing container 4, and the inside of the concave portion 17 is an exhaust space 18. Further, an exhaust port 20 is provided in a lower side wall defining the concave portion 17 of the exhaust space 18. The exhaust port 20 is a vacuum exhaust system 22 that is provided with a pressure control valve or a vacuum pump (not shown), and the vacuum exhaust system 22 can evacuate the inside of the processing container 4 to maintain a predetermined pressure. A mounting table device 24 for mounting the semiconductor wafer -12-200941621 of the object to be processed is provided in the processing container 4. The stage device 24 has a mounting table 26 on which the wafer W is actually placed, and a leg portion 28 that extends to the center portion of the lower surface of the mounting table 26 to extend the horizontal support mounting table 26 downward. The leg portion 28 is supported by the bottom portion 16A of the concave portion 17 of the predetermined venting space 18 at its lower end. The leg portion 28 has a hollow interior, that is, a cylindrical shape, and the lower end is opened. Both the mounting table 26 and the leg portion 28 are formed of, for example, a ceramic material such as A1N. Further, one of these may be formed of a ceramic material. φ A resistance heating heater 30 is embedded in the upper side of the mounting table 26 as a heating means for heating the wafer W placed thereon. The resistance heating heater 30 is composed of, for example, a molybdenum wire. As shown in FIG. 2, the resistance heating heater 30 is concentrically divided into an inner region heater 32A and an outer region heater 32B. The two heating zones forming the inner heating zone and the outer heating zone are used to control the heating temperature in each zone. Then, the ceramic heater is constituted by the mounting table 26 made of a ceramic material and the resistance heating heater 30. 〇 In addition, the number of this area is not particularly limited, and may be more than three areas.
各區域的加熱器32 A、32B的連接端子是位於載置台 26的中心部（參照圖1 )，在該等連接端子分別藉由例如 Ni-Au奸焊來接合例如由Ni所構成的給電棒36A、 36B 。該等給電棒36A、 36B是延伸至下方，通過中空狀的 脚部28内來延伸至外部，連接至供給電力的電源部37。 另外，給電棒3 6A、3 6B是在圖1中分別只記載1根 ，但實際是分別設置2根。 -13- 200941621 陶瓷製的脚部28的上端是被氣密接合於載置台26的 中央部的下面。並且，此脚部28的下端部的安裝凸緣部 28A會被氣密安裝於規定排氣空間18的凹狀部17的底部 16A。另外，在脚部28内會被供給N2氣體等的惰性氣體 〇 被處理體的半導體晶圓爲3 00mm晶圓的情況時，載 置台26的直徑是3 40mm程度，脚部28的直徑是40〜 5 0 m m程度。 在載置台26的背面側（下面側）的中央部是使對應 於最内周的加熱區域，在此是使對應於内側加熱區域34A 來設置溫度測定部38，可測定内側加熱區域34A的溫度 。此溫度測定部3 8，例如可使用熱電偶，藉由融着來將此 熱電偶安裝於載置台26的背面中央部。此情況，由此熱 電偶所構成的溫度測定部38是形成被收容於脚部28内的 狀態，因此熱電偶不會暴露於被供給至處理容器4内的各 種氣體，防止熱電偶腐蝕。 從上述溫度測定部38延伸的配線40是貫通底部16A 側來引出至外側，連接至例如由微處理器（電腦）所構成 的電源控制部42。然後，此電源控制部42可根據上述溫 度測定部3 8的檢測値來控制上述加熱區域的各加熱器 32A、32B。此情況，上述内側加熱區域34A的内側區域 加熱器32 A是被反餽控制成可維持成膜處理的製程溫度。 相對的，外側加熱區域34B的外側區域加熱器32B是無論 内側區域加熱器32A以電流控制、電壓控制、電力控制等 200941621 哪種的控制形態來控制，皆是以往内側區域加熱器32A的 供給電力作爲基準，設定成被供給以預定的安全供給電力 比來決定的電力，進行開迴路的控制。 例如某製程溫度的安全供給電力比爲〇.8時，是控制 成往内側區域加熱器32A的供給電力的0.8倍的電力會被 供往外側區域加熱器32B。 在此所謂電流控制是將對應於設定溫度與實際溫度的 φ 差分之操作量作爲電流的形式來輸出者，所謂電壓控制是 將此差分作爲電壓來輸出者，所謂電力控制是將此差分作 爲電力來輸出者。 上述安全供給電力比是以各加熱區域間的溫度差可成 爲不會損壞上述載置台26的範圍之方式來決定者，依製 程溫度，有時也會有即使令膜厚的面内均一性少許降低也 要能夠防止載置台26的破損來設定電力比的情況。有關 此點會在往後欽述。 〇 上述電源控制部42是除了控制載置台裝置24的動作 以外’還一倂具有控制處理裝置2的動作全體的機能，電 源控制部42是連接記憶媒體44，其係記憶用以控制動作 的程式。此記憶媒體44可例如使用軟碟或快閃記憶體等 〇 另一方面，在上述載置台26中貫通其上下方向而形 成有複數的銷孔46，在各銷孔46中，例如石英製的頂銷 50會在遊嵌狀態下被収容著，其下端會被共通連結於連結 環48。然後，上述連結環48是貫通至容器底部而被連結 -15- 200941621 至設成可上下移動的出没桿52的上端，此出没桿52的下 端是被連接至汽缸54。藉此，可使上述各頂銷50在晶圓 W的交接時從各銷孔46的上端往上方出没。並且，在上 述出没桿52對容器底部的貫通部是設有可伸縮的波紋管 56，上述出没桿50可一面維持處理容器4内的氣密性一 面昇降。 其次，說明有關利用以上那樣構成的處理裝置2來進 行的成膜方法（含溫度控制方法）。 首先，若使頂銷50上下作動，將未處理的半導體晶 圓W載置於被維持於製程溫度的載置台26上而密閉處理 容器4内的話，則會藉由真空排氣系22來將此處理容器4 内維持於預定的製程壓力，且由氣體供給手段的淋浴頭部 6來將預定的處理氣體（成膜氣體）導入至處理容器4内 ’藉由CVD來對晶圓W形成預定的薄膜。例如藉由 CVD來形成TiN膜時，在淋浴頭部6的一方氣體空間8A 供給NH3氣體，在另一方的氣體空間8B供給TiCl4 + N2氣 體，使該等的各氣體混合於處理空間S内來進行TiN膜的 成膜處理。 在進行如此的成膜處理時，上述電源控制部42是根 據來自設於載置台26的下面中央部之由熱電偶所構成的 溫度測定部38的測定値，經由上述電源部37來控制往區 域加熱器32A、 32B的操作量。例如往内側加熱區域 34A的内側區域加熱器32A之供給電壓是以能夠維持此成 膜處理的製程溫度之方式反餽控制（電壓控制）。相對的 -16- 200941621 ’外側加熱區域34B的外側區域加熱器32B是以往上述内 側區域加熱器32A的供給電力（不是供給電壓）爲基準， 設定成以預定的安全供給電力比來決定的電力，進行開迴 路的控制。藉此，可防止載置台26的内外周間的溫度差 過度大，可阻止載置台26破損。 此時的載置台26的溫度分布，是載置台26的中央部 的溫度最低，隨著接近周邊部（邊緣部）溫度會變高的溫 H 度分布，亦即形成中央冷的溫度分布狀態。參照圖3來説 明此溫度分布的狀態。 圖3是表示半導體晶圓的直徑方向的處理氣體濃度與 溫度分布的關係模式圖。上述處理氣體是一般從設於處理 容器的頂部的淋浴頭部6來供給至處理空間，使一面流下 至處理空間一面朝載置台26的周邊部大略均等地擴散， 而由載置台26的下方排氣。因此，從淋浴頭部6供給至 處理空間的處理氣體的濃度是在晶圓中央部高，隨著往邊 φ 緣部行進而漸低。因此，晶圓溫度不會全面均一，在氣體 濃度高的部份（中央部）的反應會被促進，此部份的膜厚 會比其他的部份（邊緣部）更厚，爲不理想。 於是，如圖3所示，藉由設定成晶圓中央部的晶圓溫 度最低，隨著往邊緣部行進而溫度變高之中央冷的溫度分 布狀態，可抑止在中央部的反應，其結果設定成膜厚的面 内均一性會更高。將如此中心部的溫度設定成比晶圓的周 邊部更低的狀態稱爲中央冷狀態。另外，將相反的溫度關 係稱爲中央熱狀態。 -17- 200941621 此情況，雖也會依製程溫度而定，但直徑爲3 00mm 的晶圓時，晶圓中央部與邊緣部的溫度差At是例如5 °C程 度。 可是，可知在前述那樣的中央冷的溫度分布狀態下， 若上述溫度差ΛΑ t過大，則由陶瓷材所構成的載置台26 與由陶瓷材所構成的脚部28的接合部會發生大的應力集 中，載置台26會破損。根據本發明者等的硏究，在中央 冷的溫度分布時，上述溫度載置台At的上限値是33 °C程 度，爲了防止破損最好將溫度載置台At設定於33 °C以下 如前述般，在以往的載置台裝置的溫度控制中，有關 内側加熱器是根據在由熱電偶所構成的溫度測定部的測定 値來進行反餽控制，有關外側加熱器的溫度是使對應於製 程溫度，預先求取膜厚的面内均一性形成最佳的電流比或 電壓比，以内側加熱器作爲基準，以能夠維持對應於電流 比或電壓比的電流或電壓之方式開迴路控制外側加熱用加 熱器。 但，就如此以往的控制方法而言，一旦在被溫控成 700°c程度的載置台26上，加上載置室溫的晶圓W等之熱 的侵犯，則載置台的中央部與邊緣部之間會發生大的溫度 差，會有因此而造成載置台26破損等的問題。如此形成 溫度差大的原因之一，可想像是因爲由鉬線所構成的加熱 器的電阻會依溫度而變動。 於是，本發明是取代電流比或電壓比，如前述般藉由 -18- 200941621 電力比來控制外側區域加熱器32B »此情況，若只是以使 膜厚的面内均一性能夠經常形成最好的方式來控制電力比 ，則依情況而定，也會有發生溫度差At超過3 3 °C的情形 ，因此如此的情況是設定成即使令膜厚的面内均一性稍微 降低，在載置台26也會不有產生破損那樣的電力比。 以下是說明有關求取最適的電力比、亦即安全供給電 力比的製程。首先，在一般的處理裝置中，往外側區域加 φ 熱器32B的供給電力對内側區域加熱器32A的供給電力之 比，亦即供給電力比（外側區域加熱器供給電力/内側區 域加熱器供給電力=〇UT/IN )與晶圓面内的膜厚的不均一 性的關係是形成圖4所示那樣的關係。另外，膜厚的不均 —性越少，顯示膜厚的面内均一性越良好。亦即，圖4是 顯示供給電力比爲"1 .1 "時的膜厚不均一性最少，膜厚的 面内均一性最佳。由如此的膜厚不均一性來看的最適供給 電力比是依製程溫度而有所差異。 φ 於是，首先對各種的製程溫度，例如對400〜900°C程 度的範圍内的各種製程溫度，預先求取膜厚的面内均一性 最佳的供給電力比（OUT/IN )。例如製程溫度爲汾400°C 、450°C時，供給電力比是"0.65"，製程溫度爲 5 00°C、 5 50°C時，供給電力比是”0.70"…那樣預先求取。 在實際的製程時，只要對應於製程溫度以上述那樣的 供給電力比來控制往外側區域加熱器32B的供給電力，便 可形成最適的中央冷狀態，在膜厚的面内均一性最佳的狀 態下取得薄膜，但此情況依條件會有在載置台26發生破 -19- 200941621 損的情況。 於是，爲了防止該破損的發生，而對上述供給電力比 加以限制。亦即，首先，預先在各種的製程溫度（660°C 以下），以上述電力供給比來進行對外側區域加熱器32B 的電力控制而實際進行成膜處理，此時針對載置台26是 否破損來進行檢討。另外，對内側區域加熱器32A以能夠 維持所被設定的製程溫度之方式來進行反餽控制》將此時 的結果顯示於圖5。在圖5中，横軸是表示進行實驗的加 熱器的數量。 由圖5可明確得知，此載置台是以供給電力比大略 "1·00"作爲境界分成載置台發生破裂時（圖中左側）、及 未發生破裂時（圖中右側）。因此，可知66(TC以下的製 程溫度時，只要供給電力比爲1.00以下，即在載置台26 不會發生破損。 因此’製程溫度爲660°C以下時，可取得最佳的膜厚 的面内均一性的供給電力比爲1.00以下時，將該供給電 力比設爲安全供給電力比。另一方面，可取得最佳的膜厚 的面内均一性的供給電力比超過1.00時，以"1.00”作爲該 製程溫度的安全供給電力比。亦即，在此是供給電力比超 過"1.00"時’稍微犧牲膜厚的面内均一性來謀求載置台26 的安全。 並且’有關製程溫度比660 °c大時也進行與上述同樣 的検討。其結果’可知比660 °C高的製程溫度時，若供給 電力比爲"0.82"以下，則在載置台26不會產生破損。然後 -20- 200941621 ’以上那樣取得的每製程溫度的安全供給電力比是預先記 憶於電源控制部42。因此，只要進行按照此供給電力比的 溫度控制，便可在中央冷的溫度分布狀態中，將載置台26 的内外周間的溫度差Δί控制於3 3 °C以内，可防止該破損 〇 將上述那樣求取的供給電力比的結果顯示於圖6。圖 6是表示依製程溫度所被容許的供給電力比的範圍圖表， φ 爲了參考，以往的供給電壓比的控制時的控制範圍也一倂 顯示。此圖中，越往右側，中央冷的狀態會越變大，越往 左側，越成中央熱的狀態。如上述般，製程溫度爲660°C 以下時，供給電力比是被容許於0.38〜1.00的範圍，製程 溫度爲大於660°C時，供給電力比是被容許於0.38〜0.82 的範圍。另外，實驗的結果，在中央部的溫度比晶圓邊緣 部更高的中央熱時，其溫度差是形成7〇t程度爲止，在載 置台26不會產生破損。 φ 並且，就參考所示的以往供給電壓比的控制範圍是在 右側所示領域A1的部份會有發生載置台破裂的情況，不 理想。 其次，實際進行以往的電壓比控制與本發明的電力比 控制。參照圖7A、圖7B來説明該時的加熱器溫度及操作 量的變化。 圖7A是表示以往的電壓比控制時，圖7B是表示本發 明的電力比控制時。各圖表皆左側縱軸是表示加熱器溫度 (内側區域加熱器），右側縱軸是表示操作量。在此，圖 -21 - 200941621 7A的情況是表示操作量100%爲200伏特，圖7B的情況 是表示操作量100%爲4000瓦特。此時的設定製程溫度爲 7〇〇°C，所被設定的供給電壓比（圖7A的情沅）及供給電 力比（圖7 B的情況）是分別爲"〇. 9 5 "及"0.8 2 "。 如圖示般，顯示晶圓搬入後的各加熱器的操作量的變 化及加熱器溫度的變化，在圖7A所示的以往的電壓比控 制時，晶圓搬入後，至溫度安定爲止的溫度變動量H1是 形成非常大的値。如此大的溫度變動量H1是成爲在載置 台26的内外周間引起大的溫度差的原因，其結果，使載 置台26產生破損。 相對的，在圖7B所示的本發明的電力比控制時，晶 圓搬入後，至溫度安定爲止的溫度變動量H2是形成相當 小，與圖7A的情況時作比較是形成一半的程度。其結果 ，可知在載置台26的内外周間所產生的溫度差不那麼大 ，可防止載置台26破損，顯示良好的結果。 上述實施例是說明有關實際進行製程時的載置台26 的溫度控制，但實際在載置台26的昇溫時及降溫時也需 要在載置台26不會產生破裂那樣的溫度控制。此情況， 在載置台26的昇溫時及降溫時，維持成内側加熱區域 34A的溫度比外側加熱區域34B的溫度不會低於預定的溫 度差例如3 3 °C以上的狀態。具體而言，使在中央熱的狀態 下昇降溫，或即使在中央冷的狀態也會使在其溫度差形成 3 3 °C以下的狀態下昇降溫。另外，即使在中央熱的情況時 ’若使其溫度差形成例如70°C程度以上，則如前述般因爲 200941621 載置台26會破損，所以形成以下的溫度差。 在此，參照圖8來說明載置台26的昇溫時的加熱器 的溫度變化與供給電力比的變化的狀態之一例。在此亦將 製程時的安全供給電力比設定於"0.82"。 首先，在空轉狀態，加熱器溫度是被維持於3 00 °C， 此時的供給電力比是被維持於"0.5 8"。此情況是控制成載 置台的内周溫度比外周溫度更高的中央熱的狀態。然後， φ 原封不動維持上述供給電力比，亦即原封不動維持中央熱 的狀態，使供給至兩加熱器的電力増加，藉此例如以 5°C/min程度的昇溫率來將加熱器加熱。然後，若加熱器 溫度到達製程溫度（設定溫度）的7〇(TC，則使上述供給 電力比慢慢地變化成依序接近安全供給電力比的"0.82"。 藉此，載置台的溫度分布會從中央熱的狀態依序轉移至中 央冷的狀態。 如此一來，若加熱器的溫度安定，則將晶圓載置於載 φ 置台，開始成膜處理。另外，加熱器的降溫時是以能夠逆 行上述過程的方式來控制加熱器溫度即可。 如此，加熱器的昇降溫時也能夠將載置台的内外周間 的溫度差設定成不會破裂那樣的溫度差，因此可防止載置 台的破損。 另外，本發明並非限於上述實施形態，亦可爲各種的 變形。例如，上述説明所使用的各數値例只不過是一例， 當然依載置台26或電阻加熱式加熱器30等的設計，其數 値也會變化。 -23- 200941621 又，上述實施形態是舉成膜處理時爲例來說明製程處 理，但並非限於此，亦可將本發明適用於蝕刻處理、氧化 擴散處理、·退火處理、改質處理等各種的熱處理，且在電 漿處理裝置亦可適用本發明。 又，上述實施例是舉例說明同心圓狀地設置2個加熱 區域時，但並非限於此，同心圓狀地設置3個以上的加熱 區域時亦可適用本發明。此情況，中央冷的溫度分布狀態 ，當然是以最内周的加熱區域與最外周的加熱區域之間的 溫度差爲載置台不會破裂那樣的溫度範圍，例如形成33 °C 以内那樣的溫度範圍來設定安全供給電力比。 又，被處理體並非限於半導體晶圓，亦可使用 LCD 基板、玻璃基板、陶瓷基板等。 【圖式簡單說明】 圖1是表示本發明之一實施形態的處理裝置的槪略剖 面圖。 ❹ 圖2是表示在圖1的處理裝置所具備的載置台裝置的 載置台設置的加熱機構的平面圖。 圖3是表示半導體晶圓的直徑方向的處理氣體濃度與 溫度分布的關係模式圖。 圖4是表示供給電力比與膜厚的不均的關係之一例的 圖表。 圖5是表示根據預定的電力供給比來進行對外側區域 加熱器的電力控制而實際進行成膜處理時的載置台的破損 -24- 200941621 有無的結果。 圖6是表示依製程溫度所被容許的供給電力比的範圍 〇 圖7A是表示進行以往的電壓比控制時的加熱器溫度 及操作量的變化圖表。 圖7B是表示進行本發明的電力比控制時的加熱器溫 度及操作量的變化圖表。 φ 圖8是用以說明載置台的昇溫時的加熱器的溫度變化 與供給電力比的變化狀態的一例圖表。 【主要元件符號說明】 2 :處理裝置 4 :處理容器 6 :淋浴頭部 6A、6B :氣體噴出孔 φ 8A、8B :氣體空間 1 〇 :密封構件 12 :搬出入口 1 4 :閘閥 16、16A :底部 17 :凹狀部 1 8 :排氣空間 2〇 :排氣口 22 :真空排氣系 -25- 200941621 24 :載置台裝置 26 :載置台 28 :脚部 28A :安裝凸緣部 3 0 :電阻加熱式加熱器 32A :内側區域加熱器 3 2B :外側區域加熱器 34A :内側加熱區域 3 4B :外側加熱區域 3 6A、3 6B :給電棒 3 7 :電源部 3 8 :温度測定部 4 0 :配線 42 :電源控制部 44 :記憶媒體 46 :銷孔 48 :連結環 5 0 :頂銷 52 :出没桿 5 4 :汽缸 W :晶圓 S :處理空間 -26-The connection terminals of the heaters 32 A and 32B in the respective regions are located at the center portion of the mounting table 26 (see FIG. 1 ), and the connection terminals are respectively joined by, for example, Ni-Au welding electrodes, for example, Ni. 36A, 36B. The power supply rods 36A and 36B extend downward, extend through the hollow leg portion 28 to the outside, and are connected to the power supply unit 37 that supplies electric power. In addition, although only one of the electric bars 3 6A and 3 6B is shown in Fig. 1, two are actually provided. -13- 200941621 The upper end of the leg portion 28 made of ceramic is airtightly joined to the lower surface of the central portion of the mounting table 26. Further, the attachment flange portion 28A of the lower end portion of the leg portion 28 is airtightly attached to the bottom portion 16A of the concave portion 17 defining the exhaust space 18. Further, when an inert gas such as N2 gas or the like is supplied to the leg portion 28, and the semiconductor wafer of the object to be processed is a 300 mm wafer, the diameter of the mounting table 26 is about 3 to 40 mm, and the diameter of the leg portion 28 is 40. ~ 50 mm level. The central portion on the back side (lower side) of the mounting table 26 is a heating region corresponding to the innermost circumference. Here, the temperature measuring unit 38 is provided corresponding to the inner heating region 34A, and the temperature of the inner heating region 34A can be measured. . The temperature measuring unit 3 8 can be attached to the central portion of the back surface of the mounting table 26 by, for example, a thermocouple using a thermocouple. In this case, since the temperature measuring unit 38 composed of the thermocouple is formed in the leg portion 28, the thermocouple is not exposed to various gases supplied into the processing container 4, and the thermocouple is prevented from being corroded. The wiring 40 extending from the temperature measuring unit 38 is led out to the outside through the side of the bottom portion 16A, and is connected to a power source control unit 42 composed of, for example, a microprocessor (computer). Then, the power source control unit 42 can control the heaters 32A and 32B in the heating region based on the detection 値 of the temperature measuring unit 38. In this case, the inner region heater 32A of the inner heating region 34A is controlled to be feedback-controlled to maintain the film forming process. In contrast, the outer region heater 32B of the outer heating region 34B is controlled by any of the control modes of current control, voltage control, power control, and the like in the inner region heater 32A, and is the power supply of the conventional inner region heater 32A. As a reference, it is set to be supplied with electric power determined by a predetermined safe supply electric power ratio, and control of the open circuit is performed. For example, when the safe supply electric power ratio of a certain process temperature is 〇8, the electric power that controls 0.8 times of the electric power supplied to the inner area heater 32A is supplied to the outer area heater 32B. Here, the current control is to output an operation amount corresponding to the difference between the set temperature and the actual temperature as a current. The voltage control is to output the difference as a voltage. The so-called power control uses this difference as the power. To the exporter. The safety supply power ratio is determined such that the temperature difference between the heating zones is such that the range of the mounting table 26 is not damaged. Depending on the process temperature, there may be a slight in-plane uniformity of the film thickness. It is also possible to reduce the damage of the mounting table 26 and set the power ratio. This will be explained later. The power supply control unit 42 has a function of controlling the entire operation of the processing device 2 in addition to the operation of the control stage device 24, and the power supply control unit 42 is connected to the memory medium 44, which stores a program for controlling the operation. . The memory medium 44 can be, for example, a floppy disk or a flash memory. On the other hand, a plurality of pin holes 46 are formed in the mounting table 26 so as to penetrate the vertical direction thereof, and each of the pin holes 46 is made of, for example, quartz. The top pin 50 is housed in the snap-fit state, and the lower end is commonly coupled to the link ring 48. Then, the connecting ring 48 is connected to the bottom of the container and connected to the upper end of the detachment rod 52 which is set to be movable up and down, and the lower end of the ejector rod 52 is connected to the cylinder 54. Thereby, each of the above-described top pins 50 can be ejected upward from the upper end of each pin hole 46 at the time of the transfer of the wafer W. Further, the bellows 56 is provided with a bellows 56 which is stretchable in the penetrating portion of the container rod at the bottom of the container, and the hair rod 50 can be raised and lowered while maintaining the airtightness in the processing container 4. Next, a film forming method (including a temperature control method) performed by the processing apparatus 2 configured as described above will be described. First, when the top pin 50 is moved up and down, and the unprocessed semiconductor wafer W is placed on the mounting table 26 maintained at the process temperature to seal the inside of the processing container 4, the vacuum exhaust system 22 is used. The processing container 4 is maintained at a predetermined process pressure, and a predetermined processing gas (film forming gas) is introduced into the processing container 4 by the shower head portion 6 of the gas supply means. The wafer W is formed by CVD. Film. For example, when the TiN film is formed by CVD, NH 3 gas is supplied to one gas space 8A of the shower head 6 , TiCl 4 + N 2 gas is supplied to the other gas space 8B, and the respective gases are mixed in the processing space S. A film formation treatment of the TiN film was performed. In the film forming process, the power source control unit 42 controls the area to the area via the power supply unit 37 based on the measurement unit 温度 from the temperature measuring unit 38 including the thermocouple provided at the central portion of the lower surface of the mounting table 26. The amount of operation of the heaters 32A, 32B. For example, the supply voltage to the inner region heater 32A of the inner heating region 34A is feedback control (voltage control) in such a manner as to maintain the process temperature of the film formation process. In the outer region heater 32B of the outer heating region 34B, the electric power is determined by the predetermined supply power ratio based on the supply power (not the supply voltage) of the inner region heater 32A. Perform open loop control. Thereby, the temperature difference between the inner and outer circumferences of the mounting table 26 can be prevented from being excessively large, and the mounting table 26 can be prevented from being damaged. The temperature distribution of the mounting table 26 at this time is the temperature at which the temperature in the central portion of the mounting table 26 is the lowest, and the temperature rises toward the peripheral portion (edge portion), that is, the temperature distribution state in which the central portion is cooled. The state of this temperature distribution will be explained with reference to FIG. Fig. 3 is a schematic view showing the relationship between the concentration of the processing gas in the radial direction of the semiconductor wafer and the temperature distribution. The processing gas is generally supplied from the shower head portion 6 provided at the top of the processing container to the processing space, and is diffused to the processing space to be substantially uniformly diffused toward the peripheral portion of the mounting table 26 while being placed under the mounting table 26 exhaust. Therefore, the concentration of the processing gas supplied from the shower head 6 to the processing space is high at the center portion of the wafer, and gradually decreases as the edge of the side φ travels. Therefore, the wafer temperature is not uniform, and the reaction in the portion where the gas concentration is high (center portion) is promoted. The film thickness of this portion is thicker than other portions (edge portions), which is not preferable. Therefore, as shown in FIG. 3, by setting the temperature of the wafer at the center of the wafer to be the lowest, the temperature of the central portion of the temperature which is higher in temperature as it travels toward the edge portion can suppress the reaction at the center portion, and as a result, the result is suppressed. The in-plane uniformity of the film thickness is set to be higher. The state in which the temperature of the center portion is set to be lower than the peripheral portion of the wafer is referred to as a central cold state. In addition, the opposite temperature relationship is referred to as the central thermal state. -17- 200941621 In this case, depending on the process temperature, when the wafer has a diameter of 300 mm, the temperature difference At between the center portion and the edge portion of the wafer is, for example, 5 °C. However, in the above-described central cold temperature distribution state, when the temperature difference ΛΑ t is too large, the joint between the mounting table 26 made of a ceramic material and the leg portion 28 made of a ceramic material is large. When the stress is concentrated, the mounting table 26 is broken. According to the inventors of the present invention, the upper limit 値 of the temperature mounting table At is about 33 ° C in the central cold temperature distribution, and it is preferable to set the temperature mounting table At to 33 ° C or less in order to prevent breakage. In the temperature control of the conventional stage device, the inner heater is subjected to feedback control based on the measurement 値 of the temperature measuring unit constituted by the thermocouple, and the temperature of the outer heater is set to correspond to the process temperature. The in-plane uniformity of the film thickness is determined to form an optimum current ratio or voltage ratio, and the inner heating heater is used as a reference to open the circuit to control the external heating heater so as to maintain a current or voltage corresponding to the current ratio or the voltage ratio. . However, in the conventional control method, when the heat of the wafer W such as the room temperature is applied to the mounting table 26 that is temperature-controlled to 700 ° C, the center portion and the edge of the mounting table are placed. A large temperature difference occurs between the portions, which may cause damage to the mounting table 26 and the like. One of the reasons for the large temperature difference is that the resistance of the heater composed of the molybdenum wire varies depending on the temperature. Thus, the present invention replaces the current ratio or the voltage ratio, and the outer region heater 32B is controlled by the power ratio of -18-200941621 as described above. This case is only necessary to make the in-plane uniformity of the film thickness often formed. In order to control the power ratio, depending on the situation, there may be a case where the temperature difference At exceeds 3 3 ° C. Therefore, the case is set such that even if the in-plane uniformity of the film thickness is slightly lowered, the mounting table is placed. 26 There will be no power ratio as a result of damage. The following is a description of the process for obtaining the optimum power ratio, that is, the safe supply ratio. First, in a general processing apparatus, the ratio of the supplied electric power of the φ heater 32B to the electric power supplied to the inner area heater 32A, that is, the supply electric power ratio (the outer area heater supply electric power/inner area heater supply) is added to the outer area. The relationship between the electric power = 〇 UT / IN ) and the film thickness in the wafer surface is such that the relationship shown in FIG. 4 is formed. Further, the less the unevenness of the film thickness, the better the in-plane uniformity of the display film thickness. That is, Fig. 4 shows that the film thickness unevenness is the smallest when the supply electric power ratio is "1.1 ", and the in-plane uniformity of the film thickness is optimum. The optimum power supply ratio in terms of such film thickness non-uniformity varies depending on the process temperature. φ Then, first, the optimum power supply ratio (OUT/IN) of the in-plane uniformity of the film thickness is obtained in advance for various process temperatures, for example, for various process temperatures in the range of 400 to 900 °C. For example, when the process temperature is 汾400°C and 450°C, the power supply ratio is "0.65", the process temperature is 500 °C, 5 50 °C, and the power supply ratio is "0.70"... In the actual process, if the supply power to the outer zone heater 32B is controlled in accordance with the process power ratio as described above, an optimum central cold state can be formed, and the uniformity of the film thickness is the most uniform. In the case where the film is obtained in a good state, the condition may be broken in the mounting table 26 depending on the condition. Therefore, in order to prevent the occurrence of the damage, the supply power ratio is limited. In the various process temperatures (660 ° C or lower), the power control of the outer zone heater 32B is performed in advance with the power supply ratio described above, and the film formation process is actually performed. In this case, it is checked whether the mounting table 26 is damaged or not. The inner area heater 32A performs feedback control so that the set process temperature can be maintained. The result at this time is shown in Fig. 5. In Fig. 5, the horizontal axis indicates that the actual operation is performed. The number of heaters tested. It can be clearly seen from Fig. 5 that the mounting table is based on the supply power ratio of "1" and "00" as the boundary into the mounting table when the rupture occurs (left side in the figure), and when no rupture occurs ( Therefore, it can be seen that 66 (the process temperature below TC is as long as the supply power ratio is 1.00 or less, that is, the mounting table 26 is not damaged. Therefore, when the process temperature is 660 ° C or lower, the best is obtained. When the ratio of the in-plane uniformity of the film thickness is 1.00 or less, the ratio of the supplied electric power is set to the ratio of the safe electric power supply. On the other hand, the ratio of the in-plane uniformity of the optimum film thickness is more than At 1.00, "1.00" is used as the safe supply-to-electricity ratio of the process temperature. That is, here, the supply-to-electricity ratio exceeds "1.00" when the in-plane uniformity of the film thickness is slightly sacrificed to obtain the mounting table 26 In the case of the process temperature of 660 °c, the same as above is performed. The result is 'when the process temperature is higher than 660 °C, if the power supply ratio is less than <0.82" Setting 2 6. There is no damage. Then, -20-200941621 'The safety supply ratio per process temperature obtained as described above is stored in advance in the power supply control unit 42. Therefore, the temperature control according to the supply power ratio can be performed in the center. In the cold temperature distribution state, the temperature difference Δί between the inner and outer circumferences of the mounting table 26 is controlled to be within 3 3 ° C, and the result of preventing the damage 〇 from the supply electric power ratio obtained as described above is shown in Fig. 6 . It is a range chart showing the ratio of the supplied electric power to the allowable process temperature. φ For reference, the control range at the time of control of the conventional supply voltage ratio is also displayed. In this figure, the more the right side is, the more the central cold state becomes. As it goes to the left side, it becomes a central hot state. As described above, when the process temperature is 660 ° C or lower, the supply electric power ratio is allowed to be in the range of 0.38 to 1.00, and when the process temperature is more than 660 ° C, the supply electric power ratio is allowed to be in the range of 0.38 to 0.82. Further, as a result of the experiment, when the temperature in the center portion is higher than the center heat of the wafer edge portion, the temperature difference is about 7 〇t, and no damage occurs on the mounting table 26. In addition, the control range of the conventional supply voltage ratio shown in the figure is a case where the stage is broken in the portion of the field A1 shown on the right side, which is not preferable. Next, the conventional voltage ratio control and the power ratio control of the present invention are actually performed. The change in the heater temperature and the operation amount at this time will be described with reference to Figs. 7A and 7B. Fig. 7A shows the conventional voltage ratio control, and Fig. 7B shows the power ratio control of the present invention. The vertical axis on the left side of each graph indicates the heater temperature (inside area heater), and the right vertical axis indicates the amount of operation. Here, the case of Fig. -21 - 200941621 7A indicates that the operation amount 100% is 200 volts, and the case of Fig. 7B indicates that the operation amount 100% is 4000 watts. At this time, the set process temperature is 7 〇〇 ° C, and the set supply voltage ratio (in the case of FIG. 7A) and the supply power ratio (in the case of FIG. 7B) are respectively "〇. 9 5 ""0.8 2 ". As shown in the figure, the change in the operation amount of each heater after the wafer is carried in and the change in the heater temperature are displayed, and the temperature until the temperature is stabilized after the wafer is carried in the conventional voltage ratio control shown in FIG. 7A. The amount of change H1 is a very large flaw. Such a large temperature fluctuation amount H1 causes a large temperature difference between the inner and outer circumferences of the mounting table 26, and as a result, the mounting table 26 is damaged. On the other hand, in the power ratio control of the present invention shown in Fig. 7B, the temperature fluctuation amount H2 until the temperature is stabilized after the wafer is carried in is relatively small, and is halfway compared with the case of Fig. 7A. As a result, it was found that the temperature difference generated between the inner and outer circumferences of the mounting table 26 was not so large, and the mounting table 26 was prevented from being damaged, and good results were exhibited. In the above embodiment, the temperature control of the mounting table 26 during the actual process is described. However, in the case of the temperature rise of the mounting table 26 and the temperature drop, the temperature control of the mounting table 26 is not required. In this case, at the time of temperature rise and temperature drop of the mounting table 26, the temperature of the inner heating region 34A is maintained at a temperature lower than a predetermined temperature difference of, for example, 33 °C or higher than the temperature of the outer heating region 34B. Specifically, the temperature is raised and lowered in a state where the center is hot, or the temperature is raised and lowered in a state where the temperature difference is 3 3 ° C or lower even in a state where the center is cold. In addition, when the temperature difference is, for example, about 70 °C, the mounting table 26 is broken as described above, and the following temperature difference is formed. Here, an example of a state in which the temperature change of the heater and the supply electric power ratio change during the temperature rise of the mounting table 26 will be described with reference to Fig. 8 . Here, the safety supply ratio at the time of the process is also set to "0.82". First, in the idling state, the heater temperature is maintained at 300 ° C, and the supply-to-electric ratio at this time is maintained at "0.5 8". In this case, the state in which the inner circumference temperature of the stage is higher than the outer circumference temperature is controlled. Then, φ is maintained in a state where the supply power ratio is maintained, that is, the state in which the central heat is maintained as it is, and the electric power supplied to the two heaters is increased, whereby the heater is heated, for example, at a temperature increase rate of about 5 °C/min. Then, if the heater temperature reaches 7 〇 (TC of the process temperature (set temperature), the above-mentioned supply electric power ratio is gradually changed to the ratio of the safety supply electric power ratio "0.82" in this order. The temperature distribution is sequentially transferred from the central heat state to the central cold state. In this way, if the temperature of the heater is stabilized, the wafer is placed on the load φ table, and the film forming process is started. In this way, the temperature of the heater can be controlled in such a manner that the above process can be reversed. When the temperature of the heater is raised and lowered, the temperature difference between the inner and outer circumferences of the mounting table can be set to a temperature difference that does not break, so that the load can be prevented. The present invention is not limited to the above embodiment, and various modifications are possible. For example, the examples used in the above description are merely examples, and of course, the mounting table 26 or the resistance heating heater 30 may be used. In addition, although the above-described embodiment is a process of the film forming process, the process is described as an example, but the present invention is not limited thereto. The present invention is applicable to various heat treatments such as etching treatment, oxidative diffusion treatment, annealing treatment, and reforming treatment, and the present invention can also be applied to a plasma processing apparatus. Further, the above embodiment is an example in which two concentric shapes are provided. In the heating zone, the present invention is also applicable to the case where three or more heating zones are provided concentrically. In this case, the central cold temperature distribution state is of course the innermost heating zone and the outermost periphery. The temperature difference between the heating regions is a temperature range in which the mounting table does not break. For example, a temperature range of 33 ° C or less is set to set a safe power supply ratio. The object to be processed is not limited to a semiconductor wafer, and an LCD may be used. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a processing apparatus according to an embodiment of the present invention. Fig. 2 is a view showing a mounting table provided in the processing apparatus of Fig. 1. A plan view of a heating mechanism provided on a stage of the apparatus. Fig. 3 is a view showing a concentration and a temperature distribution of a processing gas in a diameter direction of the semiconductor wafer. Fig. 4 is a graph showing an example of the relationship between the supply power ratio and the film thickness unevenness. Fig. 5 is a view showing the actual film formation process by performing power control on the outer zone heater in accordance with a predetermined power supply ratio. Fig. 6 is a range showing the supply electric power ratio permissible according to the process temperature. Fig. 7A is a view showing the heater temperature and the operation amount when the conventional voltage ratio control is performed. Fig. 7B is a graph showing changes in heater temperature and operation amount when the power ratio control of the present invention is performed. φ Fig. 8 is a diagram for explaining changes in the temperature change of the heater and the ratio of the supplied electric power when the stage is heated. An example of a state. [Main component symbol description] 2: Processing device 4: Processing container 6: Shower heads 6A, 6B: Gas ejection holes φ 8A, 8B: Gas space 1 〇: Sealing member 12: Carrying out the inlet 1 4 : Gate valve 16, 16A: bottom 17: concave portion 18: exhaust space 2: exhaust port 22: vacuum exhaust system - 25 - 200941621 24: mounting table device 26: mounting table 28: foot 28A: mounting Flange portion 30: resistance heating heater 32A: inner region heater 3 2B: outer region heater 34A: inner heating region 3 4B: outer heating region 3 6A, 3 6B: power supply bar 3 7 : power supply portion 3 8 Temperature measuring unit 40: Wiring 42: Power supply control unit 44: Memory medium 46: Pin hole 48: Connecting ring 5 0: Top pin 52: Fitting rod 5 4: Cylinder W: Wafer S: Processing space -26-