200304673 玖、發明說明 【發明所屬之技術領域】 本發明，係關於藉由電漿處理來除去導入於基板材料 中之損傷。特別是，關於基板材料與半導體元件之製造方 法，包含基板材料改質之步驟’而將使用於半導體積體電 路等之金屬-絕緣體-半導體元件、太陽電池與薄膜電晶 體（TFT)等之半導體元件之製作中導入之電漿損害予以除 去。 【先前技術】 基板材料與半導體元件，特別是半導體積體電路、太 陽電池、薄膜電晶體等的半導體元件之製程中，係廣泛的 採用著使用電漿之基板材料之處理與加工、薄膜堆積。 由於該電漿處理，損傷被導入於基板材料中。若在該 損傷殘留的狀態下製成半導體，則會使半導體元件之特性 惡化係眾所周知。因此，設置藉由電漿處理來除去損傷之 步驟。雖依材料而只藉由加熱來進行，在該情況之加熱步 驟一般都是在高溫（例如600〜900°C )進行。 然而，由於高溫加熱而有導入新的損傷、摻雜物擴散 之問題點。又，也有如氫化非晶質矽等，由於高溫加熱， 使氫脫離而導致特性顯著的惡化之情況。 【發明內容】 本發明之目的，係能將因電漿處理所造成的損傷，以 比習知的方法更低溫的方式來加以除去。爲達成前述目的 ，本發明之基板材料製造方法，係在層堆積、處理或加工 200304673 之步驟中包含電漿處理，其特徵在於，具備： 在電漿處理後，在前述基板材料之電漿處理面上堆積 具有基板材料改質機能之金屬薄膜之步驟；及 在具有前述金屬薄膜之狀態下，將前述基板材料在氧 化性環境氣氛中加熱處理而除去電漿損傷之步驟。 具有基板材料改質機能之金屬，係指具有使氧分子或 臭氧分子分解之觸媒機能之金屬。 透過該金屬薄膜，將基板材料在氧化性環境氣氛中加 熱處理，藉此，可在較習知之方法更低溫下除去電漿損傷 ，藉由用來除去電漿損傷之加熱處理，可避免問題的再度 發生。 又，本發明之半導體元件之製造方法，其特徵在於： 在藉由本發明除去電漿損傷之基板材料上製成半導體元件 。該基板材料由於已除去電漿損傷，故所得到之半導體元 件之特性良好。 【實施方式】 除去電漿損傷、具有基板材料改質機能之金屬，以鉑 或鈀爲佳。這些金屬在低溫下除去電漿損傷，改質基板材 料之機能上極爲優異。 用以除去電漿損傷之金屬薄膜之堆積方法，只要係可 控制薄膜之膜厚的方法，並沒有特別限制。較佳的方法爲 蒸鍍法或電解電鍍法。在此，「蒸鍍法」係使用意味在真 空中之物理的堆積法之廣義的意義，加熱或衝擊蒸鍍源來 產生蒸鍍粒子之方法沒有特別限制，電阻加熱、濺鍍、電 200304673 子束加熱、電子束衝擊、離子濺鍍等，可使用各種的方法 〇 具有基板材料改質機能之金屬，爲了充分發揮除去電 漿損傷之作用，其堆積膜厚以〇.5nm〜500nm的範圍爲佳， 而以2〜10nm更佳。該堆積膜厚若太薄則難以均一的堆積， 若太厚則基板材料之改質機能難以發揮。 除去電漿損傷之加熱步驟中，作爲氧化性環境氣氛， 以下述a〜g所示之任一環境氣氛爲佳： a. 乾燥氧氣環境氣氛 b. 乾燥氧氣與非氧化性氣體之混合氣體環境氣氛 c. 含有水蒸氣之氧氣環境氣氛 d. 含有水蒸氣之氧氣環境氣氛與非氧化性氣體之混合 氣體環境氣氛 e. 臭氧環境氣氛、或臭氧與其他氣體之混合氣體環境氣 氛 f. 含有N20之氧氣環境氣氛 g. 含有NO之氧氣環境氣氛。 在除去電漿損傷之加熱步驟中之加熱處理溫度係較習 知之加熱處理溫度爲低之600 °C以下，其溫度範圍爲 25〜600°C。即使是藉由在低溫下之加熱處理也可達成本發 明之目的，例如在l〇〇°C以下之低溫也有效果，但是較花費 時間。 作爲對象之電漿處理，係包含氮化及氧化等之加工處 理以及薄膜堆積，其方法包含電漿CVD法、濺射蒸鍍法、 200304673 雷射燒蝕法、電子衝擊法、離子蝕刻法等。 作爲除去電漿損失之對象的材料有：矽基板、氮化膜 、氧化膜、氧氮化膜、多晶矽膜，除此之外，還可舉出高 介電體膜與強介電體膜。高介電體膜與強介電體膜可舉出 使用濺射蒸鍍法、雷射燒蝕法、電漿支援MOCVD ( Metal Organic Chemical Vapor Deposition金屬有機化學氣相沉積 )法等之電漿法製成之Zr02、Hf02、Ti02、Ta205、PZT [Pb(ZrxTi1.x)03] ^ BST[(BaxSr1_x)Ti03] ^ SBT(SrBi2Ta209) ^ BIT(Bi4Ti3012)等。 如此，依本發明之較佳形態，在具有電漿損傷之基板 材料上堆積厚度在0.5〜500mn之範圍之鈾或鈀，然後藉由 在600°C以下之溫度並且在氧化性環境氣氛中進行熱處理來 改貪基板材料，而可有效率的製成高品質之基板材料。 爲了除去電漿損傷所使用之鈾與鈀等之金屬薄膜在之 後除去也可。然而，也可殘留該金屬薄膜，在該狀態下， 或進一步在其上堆積相同之金屬或其他金屬作爲半導體元 件之電極與配線來利用之故，利用該金屬薄膜之電漿損傷 除去方法是合理的。 以下，使用實施例更具體的說明本發明。 <實施例1 > 依本發明，使用圖1來說明藉由除去電漿損傷來改質 基板材料之第1實施例。在本實施例中，說明於改質基板 材料後，到使用該基板材料作爲元件來形成半導體積體電 路所使用之 MNOS (Metal Nitride Oxide Semiconductor 金 200304673 氮氧半導體）電容。 (a) 首先，如第1圖（a)所示，在矽基板1上，形 成元件分離領域2、與元件形成領域之活性領域4。藉由將 LOCOS (Local oxidation of Silicon 石夕之局咅 15氧化）構造之 氧化膜以1000°C之水蒸氣氧化來形成500nm之膜厚，作爲 元件分離領域2。在活性領域4之表面上，存在有作爲自然 氧化膜3之膜厚約lnm之Si02膜。 作爲矽基板1，係使用藉由拉晶法（CZ法）來製成在 p型導電性（100)面方位，且電阻率10〜15 Ω cm之單晶矽 基板，作爲元件分離領域2之通道限位片（Channel stopper) ，藉由眾所周知的離子注入法，以50keV之加速能注入， 來得到2Xl013cnT3(atom)濃度之硼。 (b) 接著，如第1圖（b)所示，在洗淨矽基板1之 表面後，將該砂基板1浸漬於濃度爲0·5ν〇1%之氫氟酸（ HF)水溶液中5分鐘，除去活性領域4上之雜質以及自然 氧化膜3而製成潔淨之矽表面5。在此之洗淨係以氨、雙氧 水以及氯化氫等眾所皆知的RCA洗淨法（W. Kern. D. Α. Plutien : RCA Review p.3 1、 187，1970 年）來進行。 (c )然後，將晶圓以超純水淸洗（洗淨）5分鐘後， 藉由在導入了氫氣與氧氣之混合氣體之電爐中，將晶圓以 850°C加熱12分鐘來形成厚5mn之熱氧化膜6 (第1圖（c ))。此時，氫氣與氧氣之流量分別爲2L/min ( L爲公升 )，以及 12L/min。 (d)接著，藉由將形成了熱氧化膜6之砂基板1，暴 200304673 露於以眾所皆知的低速電子衝擊法所生成之氮氣電漿中1 小時，使熱氧化膜6氮化而形成氧氮化矽膜7 (第1圖（d ))。低速電子衝擊法，係藉由在控制了目的氣體的壓力 之真空室中，將柵極、與鎢等之燈絲彼此對向配置，藉由 對燈絲加熱來釋放熱電子，並藉由施加正電壓於柵極來加 速該熱電子，使其與目的氣體之分子衝突而製成電漿之方 法（參考 T. Mizokuro, K. Yoneda5 Y. Todoroki and H.200304673 (1) Description of the invention [Technical field to which the invention belongs] The present invention relates to removing damage introduced into a substrate material by plasma treatment. In particular, the manufacturing method of the substrate material and the semiconductor element includes a step of reforming the substrate material, and the semiconductors such as metal-insulator-semiconductor elements used in semiconductor integrated circuits, solar cells, and thin film transistors (TFTs) will be used. Plasma damage introduced during component fabrication is removed. [Previous technology] In the manufacturing process of substrate materials and semiconductor elements, especially semiconductor integrated circuits, solar cells, and thin-film transistors, the processing and processing of substrate materials using plasma and film deposition are widely used. Due to this plasma treatment, damage is introduced into the substrate material. It is well known that if a semiconductor is formed in a state where the damage is left, the characteristics of the semiconductor element are deteriorated. Therefore, a step of removing damage by a plasma treatment is provided. Although it is performed only by heating depending on the material, the heating step in this case is generally performed at a high temperature (for example, 600 to 900 ° C). However, there are problems in that new damage is introduced due to high-temperature heating and dopant diffusion. In addition, such as hydrogenated amorphous silicon, there is a case where the characteristics are significantly deteriorated due to the release of hydrogen due to high-temperature heating. SUMMARY OF THE INVENTION The object of the present invention is to remove damage caused by plasma treatment at a lower temperature than conventional methods. In order to achieve the foregoing object, the substrate material manufacturing method of the present invention includes a plasma treatment in the steps of layer stacking, processing, or processing 200304673, and is characterized by comprising: after the plasma treatment, plasma treatment of the substrate material A step of depositing a metal thin film having a substrate material modification function on the surface; and a step of removing the plasma damage by heating the substrate material in an oxidizing atmosphere in a state having the metal thin film. A metal with a substrate material modification function refers to a metal having a catalyst function that decomposes oxygen molecules or ozone molecules. Through the metal thin film, the substrate material is heat-treated in an oxidizing ambient atmosphere, whereby the plasma damage can be removed at a lower temperature than the conventional method. The heat treatment used to remove the plasma damage can avoid problems. It happened again. In addition, the method for manufacturing a semiconductor element of the present invention is characterized in that a semiconductor element is fabricated on a substrate material from which plasma damage is removed by the present invention. Since the substrate material has been removed from the plasma damage, the obtained semiconductor device has good characteristics. [Embodiment] It is preferable to use platinum or palladium to remove the plasma damage and the metal having the function of modifying the substrate material. These metals remove plasma damage at low temperatures, and are excellent in the performance of modified base sheet materials. The deposition method of the metal thin film for removing the plasma damage is not particularly limited as long as it is a method capable of controlling the film thickness of the thin film. A preferred method is a vapor deposition method or an electrolytic plating method. Here, the "evaporation method" is used in the broad sense of a physical deposition method that means physical in a vacuum. There is no particular limitation on the method of generating or depositing particles by heating or impinging the source of vapor deposition. Resistance heating, sputtering, electricity Various methods can be used for beam heating, electron beam impact, ion sputtering, etc. Metals with substrate material modification function. In order to fully remove plasma damage, the thickness of the deposited film is in the range of 0.5 nm to 500 nm. Better, and more preferably 2-10nm. If the thickness of the deposited film is too thin, it is difficult to uniformly deposit, and if it is too thick, it is difficult to exert the modification function of the substrate material. In the heating step for removing plasma damage, as the oxidizing ambient atmosphere, any one of the following a ~ g is preferred: a. Dry oxygen environment atmosphere b. Dry oxygen and non-oxidizing gas mixed gas environment atmosphere c. Oxygen environment atmosphere containing water vapor d. Oxygen environment atmosphere containing water vapor and mixed gas environment atmosphere of non-oxidizing gas e. Ozone environment atmosphere, or mixed gas environment atmosphere of ozone and other gases f. Oxygen atmosphere containing N20 Ambient atmosphere g. Ambient oxygen atmosphere containing NO. The heat treatment temperature in the heating step for removing plasma damage is lower than the conventional heat treatment temperature by 600 ° C or lower, and the temperature range is 25 ~ 600 ° C. The purpose of the invention can be achieved even by heat treatment at a low temperature. For example, a low temperature below 100 ° C is effective, but it takes time. The target plasma processing includes processing such as nitriding and oxidation, and thin film deposition. Methods include plasma CVD, sputtering, 200304673 laser ablation, electron impact, and ion etching. . Materials for removing plasma loss include silicon substrates, nitride films, oxide films, oxynitride films, and polycrystalline silicon films. In addition to this, high-dielectric films and ferroelectric films are also mentioned. Examples of the high-dielectric film and the ferroelectric film include a plasma method using a sputtering evaporation method, a laser ablation method, and a plasma-supported MOCVD (Metal Organic Chemical Vapor Deposition) method. The produced Zr02, Hf02, Ti02, Ta205, PZT [Pb (ZrxTi1.x) 03] ^ BST [(BaxSr1_x) Ti03] ^ SBT (SrBi2Ta209) ^ BIT (Bi4Ti3012) and so on. Thus, according to a preferred form of the present invention, uranium or palladium having a thickness ranging from 0.5 to 500 mn is deposited on a substrate material having a plasma damage, and then performed at a temperature below 600 ° C in an oxidizing environment atmosphere. Heat treatment is used to change the substrate material, and high-quality substrate material can be efficiently made. Metal films such as uranium and palladium used for removing plasma damage may be removed afterwards. However, the metal thin film may be left, and in this state, or the same metal or other metal is further deposited as electrodes and wiring of the semiconductor element for use, it is reasonable to use a plasma thin film to remove the metal thin film. of. Hereinafter, the present invention will be described more specifically using examples. < Example 1 > According to the present invention, a first example of modifying a substrate material by removing plasma damage will be described with reference to Fig. 1. In this embodiment, the MNOS (Metal Nitride Oxide Semiconductor 200303673) capacitor used to form a semiconductor integrated circuit using the substrate material as an element is described after the substrate material is modified. (a) First, as shown in FIG. 1 (a), on the silicon substrate 1, an element separation region 2 and an active region 4 of the element formation region are formed. An oxide film with a LOCOS (Local oxidation of Silicon) is oxidized with water vapor at 1000 ° C to form a film thickness of 500 nm. On the surface of the active area 4, there is a SiO 2 film having a thickness of about 1 nm as the natural oxide film 3. As the silicon substrate 1, a single crystal silicon substrate with a resistivity of 10 to 15 Ω cm at a p-type conductivity (100) plane orientation by a crystal pulling method (CZ method) is used as a component separation area 2 The channel stopper is implanted with an acceleration energy of 50keV by a well-known ion implantation method to obtain 2Xl013cnT3 (atom) concentration of boron. (b) Next, as shown in FIG. 1 (b), after cleaning the surface of the silicon substrate 1, the sand substrate 1 is immersed in a 0.5% v. 1% aqueous solution of hydrofluoric acid (HF) 5 In minutes, the impurities on the active area 4 and the natural oxide film 3 are removed to make a clean silicon surface 5. The washing is performed by the well-known RCA washing method such as ammonia, hydrogen peroxide, and hydrogen chloride (W. Kern. D. A. Plutien: RCA Review p. 3 1, 187, 1970). (c) Then, the wafer is rinsed (washed) with ultrapure water for 5 minutes, and then the wafer is heated to 850 ° C for 12 minutes to form a thick film in an electric furnace in which a mixed gas of hydrogen and oxygen is introduced. 5mn thermal oxide film 6 (Fig. 1 (c)). At this time, the flow rates of hydrogen and oxygen were 2 L / min (L is liter) and 12 L / min. (d) Next, the thermally oxidized film 6 is nitrided by exposing the sandy substrate 1 on which the thermally oxidized film 6 is formed, and exposed to the nitrogen plasma generated by a known low-speed electronic impact method for one hour, thereby nitriding the thermally oxidized film 6. A silicon oxynitride film 7 is formed (Fig. 1 (d)). The low-speed electron impact method is to arrange a grid, a filament, and tungsten filaments in a vacuum chamber in which the pressure of a target gas is controlled to oppose each other, release hot thermionic electrons by heating the filament, and apply a positive voltage. A method of accelerating the hot electrons at the grid to cause them to collide with the molecules of the target gas to make a plasma (refer to T. Mizokuro, K. Yoneda5 Y. Todoroki and H.
Kobayashi，J. Appl. Phys·，Vol· 85, No. 5, 2921-2928 (1999) )。此時，電漿生成環境氣氛爲0.002mbar之氮氣。用來 進行電漿生成之燈絲的加熱溫度爲120(TC，相對於燈絲之 對柵極之施加電壓爲50V。 (e) 接著，在藉由氮氣處理而形成之氧氮化矽膜7上 ，藉由除去電漿損傷來作爲具有基板材料改質機能之金屬 膜，以電子束蒸鍍法堆積約3mn厚之鈾膜8 (第1圖（e) )。此時，蒸鍍源使用約99.99wt%純度之鈾。蒸鑛速度約 0.3nm/分，蒸鍍中之矽基板溫度爲50°C，壓力爲lXl〇_4Pa 〇 (f) 之後，在電爐中，藉由在乾燥氧氣中300°C處理 1小時，而得到改質後之氧氮化矽膜9。（第1圖（f)) 〇 (g) 接著，爲了除去鉑膜8，使用蝕刻液（HN〇3 : HC1=1 ： 3)，蝕刻3次，每次1小時（第1圖（g))。 (h )爲了在如此除去了電漿損傷之基板材料之氧氮化 矽膜9上形成電極，藉由電阻加熱蒸鍍法堆積Ι/zm之鋁膜 200304673 10 (第 1 圖（h))。 (i)之後，在鋁膜10上’以眾所周知的光微影技術 形成閘極電極用之光阻圖案後’以眾所周知的蝕刻技術來 蝕刻鋁膜而形成閘極電極11 (第1圖（0 )。 接著，說明調查藉由本發明之基板材料製造方法，使 用電漿法所製成之MNOS電容之特性如何改善之結果。 第2圖係如以上之實施例所述，藉由低速電子衝擊法 來製成5nm之熱氧化膜，使用氮氣電漿進行氮化後，形成 鋁電極 <鋁/氧氮化矽膜/矽>%1^08二極體之電容-電 壓（C - V)曲線。但是，在低速電子衝擊法中之處理條件 ，係在氮氣電漿處理中之氮氣壓力爲〇.〇〇5mbar，燈絲溫度 爲1200°C，來自柵極之發射電流爲0.27A。 第2圖中’虛線所不之曲線（a )’係沒有施以除去電 漿損傷之基板材料改質處理之情況。在C- V曲線上存在 著0.7V左右的大的遲滯現象，進而C^V曲線全體被觀測 處於大的負偏壓領域。此實驗結果顯示，藉由電漿處理， 正的固定電荷以及界面位準等的缺陷位準亦即電漿損傷被 導入。 第2圖中，實線所示之曲線（b)，係在熱氧化膜施以 氮氣電漿處理後，如上述實施例所示，在氧氮化矽膜上， 以電子束蒸鍍法堆積3nm之鉑，然後在乾燥氧氣中300°C 施以1小時之加熱處理之情況。遲滯大致完全消失，C-V 曲線往正偏壓側移動。此實驗結果顯示，在本發明中，藉 由在蒸鍍鉑後之加熱處理來除去電漿損傷，而改質基板材 11 200304673 料。 表1係與第2圖同樣，顯示以本實施例製成之<鋁/ 氧氮化矽膜/矽>MNOS二極體之特性。 (表 1) _ _ 沒有處理 有除去電漿損傷之處理 閘極電壓VC=-2V時 之漏電流密度(AcnT2) 4.9 X10'9 1.5 ΧΙΟ'10 氧氮化矽膜之膜厚(nm) 5.0 5.0 介電常數 3.8 4.4 氧氮化矽膜之膜厚，不管有無除去電漿損傷之處理皆 爲 5nm 〇 設定閘極偏壓爲-2V，在蓄積狀態時，流過之漏電流 密度在沒有除去電漿損傷之情況爲4.9X l(T9Acnr2，但在施 以除去電漿損傷之處理後大幅減低至1.5X lO^Acnr2。漏 電流係透過氧氮化矽膜中之缺陷位準及界面位準而流過之 故，漏電流密度之減少係顯示電漿損傷被除去之一個證據 〇 又，介電常數藉由施以電漿損傷除去之處理，而從3.8 增加至4.4。此結果亦顯示電漿損傷被除去。 因此，顯示藉由使用本發明之方法除去電漿損傷，可 改善MNOS二極體之特性。 具有基板材料改質機能之金屬膜，並未限於實施例所 示之鉑膜，也可是鈀膜。鈀膜亦確認與鈾膜同樣具有基板 材料改質機能。又，金屬膜之形成方法，並不限於實施例 12 200304673 之電子束蒸鍍法，也可是電阻加熱蒸鍍法及濺射蒸鍍法等 其他之蒸鍍法及電解電鍍法。 依本發明之基板材料製造方法，在具有電漿損傷之基 板材料上，藉由除去電漿損傷而堆積具有基板材料改質機 能之金屬膜，然後藉由在氧化環境氣氛中加熱，可不用習 知之高溫加熱而除去電漿損傷。藉此來改善基板材料特性 ，特別可實現半導體積體電路、太陽電池、薄膜電晶體等 之半導體元件之高性能化。 產業上之可利用件 藉由使用依本發明之方法除去電漿損傷來改質基板材 料之方法，當然可適用於半導體積體電路、太陽電池、薄 膜電晶體等各種半導體元件，也可適用於其他各種用途、 基板材料。 【圖式簡單說明】 (一） 圖式部分 圖1(a)〜⑴係表示使用藉由電漿損傷之除去之基板材料 製造方法，來製造MNOS電容之方法之一實施例之步驟截 面圖。 圖2係MNOS電容之C- V曲線圖，（a)爲氧氮化矽 膜之電漿損傷未除去之情況、（b)係藉由實施例而除去氧 氮化矽膜之電漿損傷後之情況。 (二） 元件代表符號 1 矽基板 2 元件分離領域 200304673 3 自然氧化膜 4 活性領域 5 潔淨矽表面 6 熱氧化膜 7 氧氮化矽膜 8 鉑膜 9 氧氮化矽膜 10 鋁膜 11 閘極電極 14Kobayashi, J. Appl. Phys., Vol. 85, No. 5, 2921-2928 (1999)). At this time, the plasma generates nitrogen with an ambient atmosphere of 0.002 mbar. The heating temperature of the filament used for plasma generation is 120 ° C., and the applied voltage to the grid relative to the filament is 50 V. (e) Next, on the silicon oxynitride film 7 formed by nitrogen treatment, By removing the plasma damage as a metal film with substrate material modification function, a uranium film 8 with a thickness of about 3 mn was deposited by electron beam evaporation (Fig. 1 (e)). At this time, the evaporation source used was about 99.99 wt% purity uranium. The evaporation speed is about 0.3nm / min, the temperature of the silicon substrate during evaporation is 50 ° C, and the pressure is 1 × 10-4Pa 〇 (f). Processed for 1 hour at ° C to obtain a modified silicon oxynitride film 9. (Fig. 1 (f)) 〇 (g) Next, in order to remove the platinum film 8, an etching solution (HN〇3: HC1 = 1) was used. : 3), etching 3 times for 1 hour each time (Figure 1 (g)). (H) In order to form an electrode on the silicon oxynitride film 9 of the substrate material from which the plasma damage has been removed in this way, heating by resistance A 1 / zm aluminum film 200304673 10 was deposited by evaporation (Fig. 1 (h)). (I) After that, a photoresist pattern for the gate electrode was formed on the aluminum film 10 by a well-known photolithography technique. 'The gate electrode 11 is formed by etching the aluminum film by a well-known etching technique (Fig. 1 (0). Next, it will be described how the characteristics of the MNOS capacitor made by the plasma method by the substrate material manufacturing method of the present invention are used. Improved results. As shown in the above example, the second figure is a 5nm thermal oxide film made by low-speed electron impact method, and the nitrogen electrode is used for nitriding to form an aluminum electrode < aluminum / oxynitride Capacitance-Voltage (C-V) Curve of Silicon Film / Silicon>% 1 ^ 08 Diode. However, the processing conditions in the low-speed electron impact method are that the nitrogen pressure in the nitrogen plasma treatment is 0.00. 〇5mbar, the filament temperature is 1200 ° C, and the emission current from the grid is 0.27A. The curve "a" shown by the dashed line (a) "in Figure 2 is the case where the substrate material modification treatment is not applied to remove the plasma damage. There is a large hysteresis of about 0.7V on the C-V curve, and the entire C ^ V curve is observed in the large negative bias field. The experimental results show that, by plasma treatment, the positive fixed charge and the Plasma damage such as interface level In Figure 2, the curve (b) shown by the solid line is after the thermal oxidation film is subjected to nitrogen plasma treatment, as shown in the above embodiment, on the silicon oxynitride film, the electron beam is evaporated. In the case of depositing platinum at 3nm by plating, and then applying heat treatment at 300 ° C in dry oxygen for 1 hour. The hysteresis has almost completely disappeared and the CV curve has moved to the positive bias side. This experimental result shows that in the present invention, The plasma damage was removed by heat treatment after the platinum was evaporated, and the base material 11 200304673 was modified. Table 1 is the same as that in FIG. 2 and shows the < aluminum / silicon oxynitride film made in this example. / Silicon> MNOS diode characteristics. (Table 1) _ _ No treatment with plasma treatment removed Gate voltage VC = -2V Leakage current density (AcnT2) 4.9 X10'9 1.5 XIO 10'10 Silicon oxynitride film thickness (nm) 5.0 5.0 Dielectric constant 3.8 4.4 The film thickness of the silicon oxynitride film is 5nm regardless of whether or not the plasma damage is removed. ○ Set the gate bias to -2V. In the accumulation state, the leakage current density is not removed. The damage of the plasma is 4.9X l (T9Acnr2, but it is greatly reduced to 1.5X lO ^ Acnr2 after the treatment to remove the plasma damage. The leakage current is through the defect level and interface level in the silicon oxynitride film As a result, the decrease in leakage current density is an evidence that the plasma damage is removed. Also, the dielectric constant was increased from 3.8 to 4.4 by applying a plasma damage removal treatment. This result also shows that The plasma damage is removed. Therefore, it is shown that by removing the plasma damage by using the method of the present invention, the characteristics of the MNOS diode can be improved. The metal film having the substrate material modification function is not limited to the platinum film shown in the embodiment, It can also be a palladium film. The palladium film is also confirmed to have the same properties as the uranium film. It has the function of modifying the substrate material. The method for forming the metal film is not limited to the electron beam evaporation method of Example 12 200304673, but may also be other evaporation methods such as resistance heating evaporation method and sputtering evaporation method and electrolysis. Electroplating method. According to the substrate material manufacturing method of the present invention, on a substrate material having a plasma damage, a metal film having a substrate material modification function is deposited by removing the plasma damage, and then heated in an oxidizing atmosphere, Plasma damage can be removed without the conventional high-temperature heating. This can improve substrate material characteristics, and especially achieve high performance of semiconductor components such as semiconductor integrated circuits, solar cells, thin film transistors, etc. The method of modifying substrate materials by removing plasma damage by using the method according to the present invention is, of course, applicable to various semiconductor elements such as semiconductor integrated circuits, solar cells, thin film transistors, and other various applications and substrate materials. [Brief description of the drawings] (1) Figure 1 (a) ~ ⑴ of the drawing show the use of the substrate removed by plasma damage Material manufacturing method, a sectional view of the steps of one embodiment of the method for manufacturing MNOS capacitors. Figure 2 is the C-V curve diagram of MNOS capacitors, (a) is the case where the plasma damage of the silicon oxynitride film is not removed, b) The situation after the plasma damage of the silicon oxynitride film is removed by the examples. (II) Symbols of element 1 Silicon substrate 2 Element separation area 200304673 3 Natural oxide film 4 Active area 5 Clean silicon surface 6 Thermal oxidation Film 7 Silicon oxynitride film 8 Platinum film 9 Silicon oxynitride film 10 Aluminum film 11 Gate electrode 14