201213472 六、發明說明： 【發明所屬之技術領域】 本發明係關於-種用以對研磨對象物之被研磨面進行研 磨之研磨劑及研磨方法。更詳細而言，關於一種於研磨對 象物被研磨面之研磨過程中，可進行高速研磨，且長期使 ‘ 用時之穩定性優異之研磨劑及使用該研磨劑之研磨方法。 【先前技術】 作為日後期待較大發展之LED或功率器件用之基材，藍 寶石（a-AhO3)或碳化矽（Sic)、氮化鎵（GaN)等化合物單晶 圓之製造、加工技術受到關注。於該等基板上形成⑽等 結晶薄膜而製成器件，因此，低缺陷、高品質之表面亦於 結晶學方面被視作重點，且為了獲得該等低缺陷、高平滑 之表面’而使化學機械研磨（Chemical Mechanical P〇llShlng :以下有時亦稱為CMP)技術不斷受到注目。然 而’藍寶石、SiC、GaN均硬度極高，且化學穩定性亦 咼，故而，尤其於決定品質之最終階段之研磨過程中，難 、面確保°0貧一面咼效地進行研磨，從而存在研磨步驟 變得極長之問題。 於決定該等單晶基板之品質之最終研磨中，目前為止大 多數情形時一直使用氧化石夕微粒子。使用氧化石夕微粒子提 高研磨效率（研磨速度）之嘗試目前為止進行有若干次，且 提案有提高研磨粒濃度（參照非專利文獻丨）、以特定之比例 混合粒徑不同之2種以上之研磨粒（參照專利文獻1、2)、以 及提高研磨壓力/旋轉速度等。 157409.doc 201213472 先行技術文獻 專利文獻 專利文獻1:曰本國專利第4231632號公報 專利文獻2:日本國專利第4253 141號公報 非專利文獻 非專利文獻 1 : [ Scratch-free Dielectric CMP Process with Nano-colloidal Ceria Slurry], P31-34, International Conference on Planarization/CMP Technology, November 19-21, 2009 【發明内容】 發明所欲解決之問題 然而，於使用氧化矽微粒子之單晶基板之研磨中，普遍 循環使用研磨劑’必需考慮長期使用時之穩定性，而若提 高研磨粒濃度’則研磨粒會因使用而凝聚，導致研磨效率 易於大幅下降，因此，存在研磨劑長期使用時之穩定性大 幅降低之問題。關於研磨粒之混合，可列舉如下課題：目 前為止提案之混合比率，不僅研磨速度提高效果有限，而 且長期使用時之研磨劑穩定性變差。進而，若嚴格設定研 磨條件，則雖可提高研磨速度’但易誘發晶圓形狀或劃痕 等研磨缺陷之問題。 本發明係為了解決上述問題研製而成者，其目的在於提 供一種以更高速度對研磨對象物之被研磨面進行研磨，並 且長期使用時之穩定性亦優異之研磨劑及研磨方法。 解決問題之技術手段 157409.doc 201213472 本發明m種具有以下構叙用以對研磨對象物 之被研磨面進行研磨之研磨劑。 π]種研磨劑，其係用以對研磨對象物之被研磨面進 行研磨者’且含有平均一次粒徑為5〜2〇 nm之第i氧化石夕微 粒子、平均一次粒徑為40〜110 nm之第2氧化矽微粒子、以 及水且上述第1氧化矽微粒子在上述第1氧化矽微粒子與 第2氧化矽微粒子之合計量中所占之比例為〇.7〜3〇質量％。 [2] 如上述[1]之研磨劑，其中上述第丨氧化矽微粒子及上 述第2氧化矽微粒子均為膠體二氧化矽。 [3] 如上述[1]或之研磨劑，其中上述第丨氧化矽微粒子 在上述第1氧化矽微粒子與第2氧化矽微粒子之合計量中所 占之比例為1〜10質量〇/〇。 [4] 如上述[1]至[3]中任一項之研磨劑，其中上述第2氧化 石夕微粒子之平均一次粒徑為45〜丨〇〇 nrn。 [5] 如上述[1]至[4]中任一項之研磨劑，其中上述第丨氧化 石夕Μ粒子之平均一次粒徑為5〜丨5 nm。 [6] 如上述[1]至[5]中任一項之研磨劑，其中上述研磨對 象物係以修正莫氏硬度表示之硬度為10以上之單晶基板。 本發明另提供一種具有以下之構成的用以對研磨對象物 之被研磨面進行研磨之研磨方法。 [7] —種研磨方法，其係將上述[丨]至[6]中任一項之研磨 劑供給至研磨墊’使研磨對象物之被研磨面與上述研磨墊 接觸’並藉由兩者間之相對運動而進行研磨。 [8] 如上述[7]之研磨方法，其中藉由重複進行將供給至 157409.doc 201213472 上述研磨墊且已用於研磨之研磨劑回收，並將上述回收之 研磨劑再次供給至研磨墊之操作，而循環使用上述研磨 劑。 發明之效果 根據本發明之研磨劑及使用該研磨劑之研磨方法，可言 速地對研磨對象物之被研磨面進行研磨，進而可長期穩定 地進行使用。 【實施方式】 以下’對本發明之實施形態進行說明。 [研磨劑] 本發明之研磨劑係用以對研磨對象物之被研磨面進行研 磨者，且含有平均一次粒徑為5〜2〇 nm之第i氧化矽微粒 子、平均一次粒徑為40〜11〇 nm之第2氧化矽微粒子、以及 水，且上述第1氧化矽微粒子在上述第丨氧化矽微粒子與第 2氧化矽微粒子之合計量中所占之比例為〇 7〜3 〇質量％。 於本發明之研磨劑中，第1氧化石夕微粒子及第2氧化石夕微 粒子係用作研磨粒。於本發明之研磨劑中，將第旧化石夕 微粒子之平均-次粒徑及第2氧化輕粒子之平均一次粒 k刀別&為上述範圍。藉由以上述調配比例調配於研磨 則^而於進行研磨時’利㈣為研磨粒以上述調配比例 二里：在於占大部分的大粒捏之第2氧化石夕微粒子之間的 二拉搜之第1氧切微粒子，使基板與研磨㈣之摩擦力 二二:Γ較高之研磨速度。又，小粒徑之第1氧化 例二S'與大粒控之第2氧切微粒子均以上述調配比 少里子’藉此，亦有助於提高於水等分散媒中之分散 157409.doc 201213472 穩定性’從而可獲得長期使用時之穩定性。 (1)第1氧化矽微粒子及第2氧化矽微粒子 於本發明之研磨劑中，第1氧化矽微粒子及第2氧化矽微 粒子可使用除平均一次粒徑不同以外其他均相同之氧化石夕 微粒子，並且均可使用以各種公知方法製造者。例如，可 列舉如下膠體二氧化矽等氧化矽微粒子：使在氧與氫之火 焰中氣相合成有四氣化矽之煙矽或矽酸鈉進行離子交換， 或者將中和後脫氣之膠體二氧化石夕或石夕院氧化物於液相中 水解。該等之中，於本發明之研磨劑中自品種之多樣性之 觀點而言，更佳為以矽酸鈉為起始原料之膠體二氧化矽。 本發明之研磨劑所含之第丨氧化矽微粒子之平均一次粒 徑如上所述為5〜20 nm，但較佳為5〜15 nm，更佳為7〜13 nm ° 小於5 nm之第丨氧化矽微粒子有無法穩定存在之虞， 又，若使用超過20 nm之第丨氧化矽微粒子，則存在無法獲 得較佳之研磨速度之可能性。 又，本發明之研磨劑所含之第2氧化矽微粒子之平均一 次粒徑如上所述為40〜110 nm，但較佳為45〜i〇〇 nm。若使 用超過_ ΓΠΠ之第2氧切微粒子，則存在研磨對象物之 破研磨面之面精度變差之虞，而若使用小㈣nm之第2氧 化石夕微粒子，料在無法獲得較佳之研磨速度之可能性。 π再者’於本說明書中，所謂氧化石夕微粒子之平均一次粒 控’係指將利用氮氣吸附ΒΕΤ法而測定之比表面積換算成 球狀粒子之直徑所得者。 J57409.doc 201213472 進而，本發明之研磨劑中之上述第丨氧化矽微粒子與第2 氧化石夕微粒子之調配比例’係如上所述第❻切微粒子 在第1氧化矽微粒子與第2氧化矽微粒子之合計量中所占之 比例達到0.7〜30質量％之調配比例’但該調配比例較佳為 1〜1 0質量°〆❹，更佳為3〜1 0質量％。 本=明之研磨劑中之第！氧化石夕微粒子及第2氧化石夕微粒 子之含量，較佳為，於相對研磨劑總質量為1〇〜5〇質量％ 之範圍内考慮研磨速度、均一性、材料選擇性、分散穩定 性等進行適當設定，作為以氧切微粒子與第2氧切微 粒子之。3十量。第！氧化♦微粒子及第2氧化⑦微粒子之合 計含量若相對研磨劑總質量未達1〇質量％ ,則存在會無法 獲得充分之研磨速度之情形，而若超過50質量％，則Z能 確'^到與研磨粒濃度之增加相應之研磨速度之提昇，又， 存在研磨劑之黏性過度上升或促進研磨劑之凝膠化之情 形。 進而，本發明之研磨劑中之第丨氧化矽微粒子及第2氧化 石夕微粒子之合計含量’更佳為相對研磨劑總質量為Η〜3〇 質量％之範圍。 ⑺水 本發明之研磨劑所含之水，係用以使作為研磨粒之上述 第氧化矽微粒子及第2氧化矽微粒子分散，並且使視需要 而添加之其他任意成分分散、溶解之介質。關於水，並無 特別制限’但考慮到對於其他調配成分之f彡響、雜質之混 X及對pH等之影響’較佳為純水或去離子水。由於水 157409.doc 201213472 Π控制研磨劑之流動性之功能，故其含量可配合以研磨 、、又、平坦化特性等之為目標之研磨特性而適當設定。 ;ι月之研磨剑中’較佳為，在相對於研磨劑總質量 ._〜90質量从範圍内含有水。水之含量若相對研磨劑 總質量未達40質量％，則存在研磨劑之黏性變高、損及流 . 錢之情形’而若超過9〇質量。/。，則存在作為研磨粒之上 逑第1氧化石夕微粒子及第2氧化石夕微粒子之濃度降低，無法 獲得充分之研磨速度之情形。 (3)研磨劑之製備及任意成分 本發明之研磨劑，係可例如以上述調配量稱量作為必需 成刀而含有之上述⑴之第i氧化石夕微粒子及第2氧化石夕微粒 子、與（2)之水，並藉由混合而製備。 此處，於作為上述第i氧化石夕微粒子及第2氧化石夕微粒子 均使用膠體二氧化石夕之情形時，由於膠體二氧化石夕預先以 乳化石夕微粒子分散於水中之狀態進行供給，故而，可將含 有上述第1氧化矽微粒子之膠體二氧化矽、與含有上述第2 氧化矽微粒子之膠體二氧化矽以所需之比例進行混合，且 僅藉由適^之水進行稀釋即可製備本發明之研磨劑。 再者，對於本發明之研磨劑，在不損及上述本發明之效 果之範圍内，除上述（1)、（2)之必需成分以外，亦可含有 如通常之化學機械研磨用之研磨劑所含有之任意成分。 (4)研磨對象物 本發明之研磨劑係用以對研磨對象物之被研磨面進行研 磨者，作為研磨對象物並無特別限制。具體而言，可列舉 157409.doc 201213472 玻璃基板、石夕晶圓、半導體器件配線基板、化合物單晶基 板專。在該等研磨對象中，本發明之研磨劑於研磨化合物 早晶基板時可取得更大之效果，尤其可藉由用於修正莫氏 硬度之硬度為10以上之粟a其此 上之早阳基板，而較大地期待更高速 磨、長期穩定使用之效果。 作為上述修正莫氏硬度為胸上之單晶基板，具體而言 可列舉：藍寶石（α-Αΐ2〇3)基板（硬度：12)、碳化石夕㈣基 板（硬度：13)、氮化鎵（GaN)基板（硬度：13)等。本發明之 研磨劑’在該等單晶基板之中’尤其可較佳地用於藍寶石 基板之研磨。 [研磨方法] 作為使用本發明之研磨劑，對研磨對象物之被研磨面進 行研磨之方法，較佳為，一面將研磨劑供給至研磨墊，一 面使研磨對象物之被研磨面與研磨墊接觸，並藉由兩者間 之相對運動而進行研磨之研磨方法。 於上述研磨方法中，作為研磨裝置，可使用先前公知之 研磨裝置。於圖1令顯示有可用於本發明之實施形態的循 環使用研磨劑之研磨裝置之一例，以下對其進行說明，但 本發明之實施形態中所用之研磨裝置並不限定於如此構造 者0 <•亥研磨裝置1 〇，係包括保持研磨對象物1之研磨頭2、研 磨壓盤3、黏合於研磨壓盤3之表面之研磨墊4、儲存研磨 劑5之貯槽8、以及使用研磨劑供給泵7將研磨劑5自貯槽8 供給至研磨墊4之研磨劑供給配管研磨裝置1〇，係構成 157409.doc •10- 201213472 為一面自研磨劑供給配管6供給研磨劑5，一面使由研磨頭 2保持之研磨對象物1之被研磨面與研磨墊4接觸，並使研 磨頭2與研磨壓盤3相對地旋轉運動進行研磨。 使用該種研磨裝置10，可進行研磨_象物1之被研磨面 之研磨。此處，研磨裝置10係以研磨對象物之單面作為被 研磨面進行研磨之研磨裝置，但亦可例如使用於研磨對象 物之上下面配置有與研磨裝置10相同之研磨墊的兩面同時 研磨裝置，對研磨對象物之被研磨面（兩面）進行研磨。 研磨頭2不僅可進行旋轉運動，而且亦可進行直線運 動。又’研磨壓盤3及研磨墊4亦可為與研磨對象物1相同 程度或者其以下之大小。於此情形時，較佳為，可藉由使 研磨頭2與研磨壓盤3相對地進行移動，而對研磨對象物丄 之被研磨面之整面進行研磨。進而，研磨壓盤3及研磨塾4 亦可不進行旋轉運動’例如亦可為以輸送帶方式進行單向 移動。 對於此種研磨裝置10之研磨條件並無特別限制，但亦可 藉由對研磨頭2施加負荷將研磨墊4壓緊，而進一步提^研 磨壓力’提昇研磨速度。研磨壓力較佳為〜5〇 kpa& 右’但考慮到研磨速度之研磨對象物1之被研磨面内均一 性、平坦性、防止劃痕等研磨缺陷之觀點，更佳為1〇〜4〇 kPa左右。研磨壓盤3及研磨頭2之轉數較佳為5〇〜5〇〇 左右，但並不限定於此。又，研磨劑5之供給量，係根據 被研磨面構成材料或研磨劑之組成、上述各研磨條件等進 行適當調整、選擇’但例如於研磨直徑為5〇 mm之晶圓 157409.doc • 11 · 201213472 時’較佳為約5〜300 cm3/分鐘左右之供給量。 作為研磨塾4’可使用含有通常之不織布、發泡聚胺基 甲酸醋、多孔質樹脂、非多孔質樹脂等者。又，為了促進 研磨劑5對研磨墊4之供給、或者使研磨劑5恆定量地蓄積 於研磨塾4’而可對研磨墊4之表面實施栅格狀、同心圓 狀螺方疋狀專之槽加 工〇 又亦可視需要’使研磨墊調節劑接觸於研磨墊4之表 面’並一面進行研磨墊4表面之調節一面進行研磨。 又’圖1所示之研磨裝置1〇，係包含將用於研磨之研磨 劑5自研磨塾4回收之回收單元（未圖示），且構成為將回收 之研磨劑5輸送至貯槽8 ^返回至貯槽8之研磨劑5，係再次 利用研磨劑供給泵7經由研磨劑供給配管6供給至研磨墊 4。研磨劑5，係以如此之方式循環使用。 進而’於本發明之研磨方法中，亦可使用所謂流動構成 之研磨裝置’即供給至研磨墊之研磨劑於研磨中使用之 後，與上述同樣地進行回收，但每一次研磨使用後即棄用 之構成。 循環使用研磨劑之研磨方法，與每一次研磨使用後即棄 用研磨劑之研磨方法相比，可減少研磨劑之消耗量，故而 較佳。然而，隨著研磨之進行，會因研磨而使被研磨物成 分不斷混入至研磨劑中，因此，先前之研磨劑，存在易招 致研磨粒之凝聚或凝膠化，誘發研磨墊之阻塞由此降低研 磨速度之問題。根據本發明之研磨劑，不易招致因上述研 磨而產生之研磨物成分混入所造成的凝膠化或凝聚，從而 157409.doc 201213472 可抑制循環使用時之研磨速度之降低。 即，本發明之研磨劑具有初始之研磨速度較高，且抑制 以循環方式使用時之研磨速度之降低之特徵。藉此，不僅 提高研磨步驟之效率，而且亦與研磨劑之消耗量之降低' 因研磨墊之打磨或刷磨等之頻率減少而實現之停工時間之 縮短、以及研磨墊消耗量之削減相_，可有效地進行研 磨步驟’ ®此，可謂對於各種器件製造之量產性提昇的意 義極其重大。 u 實施例 以下利用實施例對本發明進行說明，但本發明並不限定 於以下之記載。例1〜6為實施例，例7〜12為比較例。 [例1] 將作為Ρ氧化石夕微粒子之平均一次粒徑為ι〇⑽之膠體 二氧化石夕⑷氧化石夕微粒子之固形物成分濃度為扣質”。 之水分散液）及作為第2氧切微粒子之平均—次粒徑為 :二膠體二氧切(第2氧切微粒子之固形物成分浪度為 / 水分散液）’以第1氧切微粒子在第！氧化石夕微 =與第2氧切微粒子之合計量中所占之調配比例達到1 之比例進行調配，並進行充分㈣。於所得之混人 液中’以第❺切微粒子與第2氧切微粒子之: =二得之研磨劑之總質量、即第1氧”微粒子 與第2乳化矽微粒子人 量0/之方4 、長 之。和水®之合計質量達到20質 ㈣φ ^ +加離子交換水，製備研磨劑。於所得之研 磨劑中’第1氧切微粗子及第2氧切微粒子係 I57409.doc -13· 201213472 成分。 於表1中，關於上述例1中所得之研磨劑中之含有第【氧 化矽微粒子及第2氧化矽微粒子之研磨粒成分，表示有各 氧化矽微粒子之平均一次粒徑、及調配比例。例丨及以下 所示之任一例（2〜12)亦為研磨劑中之研磨粒成分：水之存 在比例為20 : 80(質量比）。 再者’調配於研磨劑中之氧化矽微粒子之平均一次粒押 係為利用氮氣吸附BET法測定比表面積所得之值。以下， 例2〜12中所用之氧化矽微粒子之平均一次粒徑均為利用同 樣之方法測定所得之值。 [例2〜12] 以與例1相同之方式，將表！所示之平均一次粒徑之第！ 氧化矽微粒子與第2氧化矽微粒子作為研磨粒成分，以成 為表2所示之組成之方式進行調配’進而，以第i氧化石夕微 粒子與第2氧化石夕微粒子之合計量相對於研磨劑之總質量 之比例、即研磨粒成分之調配量達到20質量％之方式，添 加水，製備例2〜例12之研磨劑。再者，使用之氧化石夕微粒 子均為膠體二氧化矽。 [評價] 對上述所得之例1〜例12之研磨劑之研磨特性利用以下之 方法進行評價。 作為研磨特性之評價’進行⑴流動使用研磨劑時之研 磨速度之s平價、（2)循環使用研磨劑時之研磨速度之持續性 之評價。 157409.doc 201213472 <被研磨物> 於（1)、（2)之評價中均使用單晶藍寶石基板之2英吋晶圓 (信光公司製造，（0001)面，基板之厚度為420 μιη)作為被 研磨物^ <研磨方法> 使用SPEEDFAM公司製造之台式研磨裝置作為研磨裝 置。使用（1)單層IC1000之K-groove(流動使用）及（2) SUBA800-XY-groove(循環使用）（均為NITTA HaaS公司製 造）作為研磨墊’於試驗前利用MEC100-PH3.5L(三菱综合 材料公司製造）及研磨刷進行調節。 研磨’係將研磨劑之供給速度設定為（1) 1〇 cm3/分鐘（流 動使用）、（2) 100 cm3/分鐘（循環使用），研磨壓盤之轉數 设定為100 rpm ’研磨壓力設定為5 psi即34 5 kPa，研磨時 間設定為（1) 30分鐘（流動使用）、（2) 6〇分鐘（循環使用）而 進行。又，研磨劑循環使用時每6〇分鐘更換上述藍寶石基 板，途中均不進行任何研磨墊調整，連續地進行研磨。 <研磨速度> 研磨速度，係利用每一單位時間之基板之厚度變化量 (μηι/hr)進行評價。具體而言，對於上述之評價中 所用之單晶藍寶石基板’測定厚度已知之未研磨基板之質 量以及各時間研磨後之基板質量，由其差求得質量變化， 進而利用下述式算出由質量變化求得之基板之厚度於每-時間中之變化。 (研磨速度（V)之計算式） 157409.doc •15· 201213472 △ m=m0 — ml V=Am/m〇xT〇x60/t (式中，Am(g)表示研磨前後之質量變化，m0(g)表示未研 磨基板之初始質量，m 1 (g)表示研磨後基板之質量，V表示 研磨速度（μπι/hr)，T0表示未研磨基板之基板厚度（μηι)，t 表示研磨時間（min))。 <初始研磨速度> 首先，對於例1〜例12之研磨劑，按照上述研磨方法 (1)，以流動（非循環使用）研磨劑條件下之研磨速度作為初 始研磨速度進行測定、計算。再者，初始研磨速度，係求 出僅將例7中製備之平均一次粒徑為80 nm之第2氧化矽微 粒子作為研磨粒之研磨劑之初始研磨速度設為1.00時之比 率進行表示。結果顯示於表1中。 [表1] 研磨粒成分組成 評價 例 第1膠體二氧化矽 第2膠體二氧化矽 初始研磨 速度* 平均一次 調配量 平均一次 調配量 粒徑[nm] [質量％] 粒徑[nm] [質量％] 例1 10 1 80 99 1.12 例2 10 5 80 95 1.27 例3 10 10 80 90 1.24 例4 10 25 80 75 1.20 例5 17 5 80 95 1.18 例6 10 5 54 95 1.15 例7(比較例） 10 0 80 100 1.00 例8(比較例） 10 0.5 80 99.5 1.02 例9(比較例） 10 50 80 50 1.07 例10(比較例） 10 100 80 0 0.94 例11(比較例） 27 10 80 90 1.01 例12(比較例） 10 5 120 95 0.68 *將例7之研磨速度設為1.00時之研磨速度比 157409.doc •16- 201213472 <研磨速度之持續性> 其次，對於循環使用研磨劑時之研磨速度之持續性利用 以下之方法進行評價。研磨方法係遵循上述（2)之方法。循 環使用時之研磨劑之持續性，係利用進行研磨直至每60分 鐘測定、算出之研磨速度與初始之研磨速度（自研磨開始 60分鐘之研磨速度）相比下降15%為止時之藍寶石基板之累 積研磨量進行評價。將例7之研磨劑之累積研磨量設為 1.00，且藉由其比率表示循環使用時之研磨劑之持續性。 若數値大於1.00，則表示與例7之研磨劑相比，研磨速度 之維持性較佳。 此處，所謂凝膠係指分散系之一種，如溶膠等液體分散 媒之膠體，但因分散質之網狀結構而保持較高之黏性喪失 流動性，故與溶膠不同，作為系統整體成為固體狀之狀 態。 [表2] 例 研磨粒成分組成 評價 第1膠體二氧化矽 第2膠體二氧化矽 研磨速度 持續性** 平均一次 粒徑[nm] 調配量 [質量％] 平均一次 粒徑[nm] 調配量 [質量％] 例1 10 1 80 99 1.09 例2 10 5 80 95 1.42 例3 10 10 80 90 1.20 例4 10 25 80 75 1.08 例7(比較例） 10 0 80 100 1.00 例8(比較例） 10 0.5 80 99.5 1.00 例9(比較例） 10 50 80 50 凝膠化 例10(比較例） 10 100 1 80 0 凝膠化 **將例^之累積研磨量設為1.00時之累積研磨比 157409.doc •17- 201213472 由表1及表2可知，以本發明之調配比例含有本發明之粒 么的第1氧化石夕微粒子及第2氧化石夕微粒 子之研磨劑，與比 較例之研磨劑相比’研磨速度變大，λ，使用中之研磨速 度之持續性較佳、即長期使用穩定性優異。 本發明詳細地並且參照特定之實施態樣進行了說明，但 只要未脫Λ本發明之範圍與精神，則可添加各種修正或變 更之情形，對於業者而言不言自明。 本申請案係基於2010年7月9日申請之曰本專利申請案 2010-156536者，且本文中作為參照引用其内容。 產業上之可利用性 根據本發明，進行研磨之研磨對象物、尤其藍寶石（α_ Al2〇3)基板、碳化石夕（Sic)基板、氮化鎵（GaN)基板等高硬 度之化合物單晶基板之被研磨面之高速研磨成為可能，且 可提昇研磨劑之長期使用穩定性。藉此，可有助於提高該 等基板之生產率。 【圖式簡單說明】 圖1係表示可用於本發明之研磨方法的研磨裝置之一例 之圖。 【主要元件符號說明】 2 3 4 5 研磨對象物 研磨頭 研磨壓盤 研磨墊 研磨劑 157409.doc • 18 - 201213472 6 研磨劑供給配管 7 研磨劑供給泵 8 貯槽 10 研磨裝置 157409.doc -19-201213472 VI. [Technical Field] The present invention relates to an abrasive and a polishing method for grinding a surface to be polished of an object to be polished. More specifically, it relates to an abrasive which can be subjected to high-speed polishing during the polishing of the surface to be polished of the object to be polished, and which has excellent stability for a long period of time and a polishing method using the same. [Prior Art] As a substrate for LEDs or power devices that are expected to be developed in the future, the manufacturing and processing technologies for single-wafers such as sapphire (a-AhO3) or tantalum carbide (Sic) and gallium nitride (GaN) are affected. attention. A crystal film of (10) or the like is formed on the substrates to form a device. Therefore, a surface having low defects and high quality is also regarded as a focus on crystallography, and chemistry is obtained in order to obtain such low-defect, high-smooth surfaces. Mechanical polishing (Chemical Mechanical P〇ll Shlng: hereinafter sometimes referred to as CMP) technology continues to attract attention. However, 'sapphire, SiC, and GaN have extremely high hardness and chemical stability. Therefore, especially in the final stage of determining the quality of the grinding process, it is difficult to ensure that the surface is effectively polished. The steps have become extremely long. In the final polishing for determining the quality of such single crystal substrates, in most cases, oxidized fine particles have been used. In the past, there have been several attempts to improve the polishing efficiency (polishing rate) by using the oxidized stone particles. It is proposed to increase the polishing particle concentration (see Non-Patent Document 丨) and to mix two or more kinds of different particle sizes in a specific ratio. The pellets (see Patent Documents 1 and 2) and the polishing pressure/rotation speed and the like are increased. 157409.doc 201213472 Prior Art Document Patent Document Patent Document 1: Japanese Patent No. 4231632 Patent Document 2: Japanese Patent No. 4253 141 Non-Patent Document Non-Patent Document 1: [Scratch-free Dielectric CMP Process with Nano- Colloidal Ceria Slurry], P31-34, International Conference on Planarization/CMP Technology, November 19-21, 2009 [Disclosure] The problem to be solved by the invention However, in the grinding of a single crystal substrate using cerium oxide microparticles, a general cycle The use of an abrasive 'must be considered for stability in long-term use, and if the concentration of the abrasive particles is increased', the abrasive grains will agglomerate due to use, and the polishing efficiency is liable to be greatly reduced. Therefore, the stability of the abrasive is greatly reduced when used for a long period of time. problem. The mixing of the abrasive grains is as follows: The mixing ratio proposed so far has not only a limited effect of improving the polishing rate but also a deterioration in the stability of the polishing agent during long-term use. Further, if the polishing conditions are strictly set, the polishing rate can be increased, but the problem of polishing defects such as wafer shape or scratches is easily induced. The present invention has been made in order to solve the above problems, and an object of the invention is to provide an abrasive and a polishing method which are excellent in the stability of the surface to be polished of the object to be polished at a higher speed and which are excellent in long-term use. Means for Solving the Problem 157409.doc 201213472 The present invention has an abrasive composition for polishing a surface to be polished of an object to be polished. π] kinds of abrasives for polishing the surface to be polished of the object to be polished and containing ith oxidized particles having an average primary particle diameter of 5 to 2 〇 nm, and an average primary particle diameter of 40 to 110 The ratio of the second cerium oxide microparticles of nm and the water and the first cerium oxide microparticles in the total amount of the first cerium oxide microparticles and the second cerium oxide microparticles is 〇7 to 3 〇 mass%. [2] The abrasive according to [1] above, wherein the second cerium oxide microparticles and the second cerium oxide microparticles are colloidal cerium oxide. [3] The polishing agent according to the above [1], wherein the ratio of the second cerium oxide fine particles to the total amount of the first cerium oxide fine particles and the second cerium oxide fine particles is 1 to 10 mass 〇/〇. [4] The abrasive according to any one of the above [1] to [3] wherein the second primary oxide particles have an average primary particle diameter of 45 to 丨〇〇nrn. [5] The abrasive according to any one of the above [1] to [4] wherein the third primary particle diameter of the cerium oxide cerium oxide particles is 5 to 丨 5 nm. [6] The abrasive according to any one of the above [1] to [5] wherein the polishing object is a single crystal substrate having a hardness of 10 or more in terms of modified Mohs hardness. The present invention further provides a polishing method for polishing a surface to be polished of an object to be polished. [7] A polishing method for supplying the polishing agent according to any one of the above [丨] to [6] to a polishing pad 'contacting a surface to be polished of the object to be polished with the polishing pad' and by both Grinding is performed by relative motion between the two. [8] The grinding method according to [7] above, wherein the abrasive which has been supplied to the above-mentioned polishing pad of 157409.doc 201213472 and which has been used for grinding is repeatedly recovered, and the above-mentioned recovered abrasive is again supplied to the polishing pad. Operate while recycling the above abrasive. Advantageous Effects of Invention According to the polishing agent of the present invention and the polishing method using the polishing agent, the surface to be polished of the object to be polished can be rapidly polished, and the object can be stably used for a long period of time. [Embodiment] Hereinafter, embodiments of the present invention will be described. [Abrasion Agent] The polishing agent of the present invention is used for polishing a surface to be polished of an object to be polished, and contains ith cerium oxide microparticles having an average primary particle diameter of 5 to 2 Å, and an average primary particle diameter of 40 〜 The second cerium oxide fine particles of 11 〇 nm and water, and the ratio of the first cerium oxide fine particles to the total amount of the second cerium oxide fine particles and the second cerium oxide fine particles is 〇7 to 3 〇 mass%. In the polishing agent of the present invention, the first oxidized stone particles and the second oxidized stone particles are used as abrasive grains. In the abrasive of the present invention, the average primary particle diameter of the second fossil ray microparticles and the average primary particle size of the second oxidized light particles are in the above range. By blending with the above-mentioned blending ratio, the grinding is carried out, and when the grinding is carried out, the profit is the same as the above-mentioned blending ratio: in the second blending of the second oxidized fine particles of the large-sized pinch The first oxygen-cut microparticles have a frictional force between the substrate and the polishing (4): a higher polishing rate. Further, both the first oxidation example 2' of the small particle size and the second oxygen-cutting fine particle of the large particle size are both less than the above-mentioned blending ratio, and contribute to the dispersion in the dispersion medium such as water. 157409.doc 201213472 Stability' to achieve stability in long-term use. (1) The first cerium oxide microparticles and the second cerium oxide microparticles in the polishing agent of the present invention, the first cerium oxide microparticles and the second cerium oxide microparticles may be the same as the oxidized stone granules except for the average primary particle diameter. And can be used in a variety of well-known methods. For example, cerium oxide microparticles such as colloidal cerium oxide may be exemplified by a gas phase in which a soot or sodium citrate having four gasified hydrazines is gas-phase-mixed in a flame of oxygen and hydrogen, or a colloid which is degassed after neutralization. The dioxide dioxide or Shixiayuan oxide is hydrolyzed in the liquid phase. Among these, in the abrasive of the present invention, from the viewpoint of the variety of varieties, colloidal cerium oxide using sodium citrate as a starting material is more preferable. The average primary particle diameter of the cerium oxide particles contained in the abrasive of the present invention is 5 to 20 nm as described above, but preferably 5 to 15 nm, more preferably 7 to 13 nm to less than 5 nm. The cerium oxide microparticles may not be stably present, and if cerium oxide microparticles exceeding 20 nm are used, there is a possibility that a preferable polishing rate cannot be obtained. Further, the average primary particle diameter of the second cerium oxide microparticles contained in the abrasive of the present invention is 40 to 110 nm as described above, but is preferably 45 to i 〇〇 nm. When the second oxygen-cut microparticles exceeding _ ΓΠΠ are used, the precision of the surface of the object to be polished of the object to be polished is deteriorated, and if the second oxidized particles of the small (four) nm are used, the preferred polishing rate cannot be obtained. The possibility. In the present specification, the average primary particle size of the oxidized stone particles refers to the ratio of the specific surface area measured by the nitrogen adsorption method to the diameter of the spherical particles. J57409.doc 201213472 Further, in the abrasive of the present invention, the ratio of the second cerium oxide microparticles to the second cerium oxide microparticles is as described above, and the first cerium microparticles and the second cerium oxide microparticles are The proportion of the total amount is 0.7 to 30% by mass of the blending ratio 'but the blending ratio is preferably from 1 to 10% by mass, more preferably from 3 to 10% by mass. The first of the abrasives of this = Ming! The content of the oxidized stone particles and the second oxidized particles is preferably such that the polishing rate, uniformity, material selectivity, dispersion stability, etc. are considered in the range of 1 〇 to 5 〇 mass% relative to the total mass of the abrasive. It is appropriately set as the oxygen-cut microparticles and the second oxygen-cut microparticles. 3 ten. The first! When the total content of the oxidized ♦ fine particles and the second oxidized 7 fine particles is less than 1% by mass based on the total mass of the abrasive, a sufficient polishing rate may not be obtained, and if it exceeds 50% by mass, Z can be determined as '^ The increase in the polishing rate corresponding to the increase in the concentration of the abrasive particles, and the excessive increase in the viscosity of the abrasive or the promotion of gelation of the abrasive. Further, the total content of the cerium oxide cerium particles and the second oxidized particles in the polishing agent of the present invention is more preferably in the range of Η3 to 3% by mass based on the total mass of the polishing agent. (7) Water The water contained in the polishing agent of the present invention is a medium for dispersing and dissolving the above-mentioned cerium oxide fine particles and second cerium oxide fine particles as abrasive grains, and dispersing and dissolving other optional components added as needed. Regarding water, there is no particular restriction. However, it is preferable to use pure water or deionized water for the f-ringing of other compounding ingredients, the mixing of impurities X, and the influence on pH and the like. Since water 157409.doc 201213472 Π controls the fluidity of the abrasive, the content thereof can be appropriately set in accordance with the polishing characteristics aimed at polishing, flattening properties, and the like. In the grinding sword of ι月, it is preferable to contain water in a range from _~90 mass to the total mass of the abrasive. If the water content is less than 40% by mass based on the total mass of the abrasive, the viscosity of the abrasive becomes high and the flow is impaired. If the amount of money exceeds 9 〇 mass. /. Further, the concentration of the first oxidized cerium fine particles and the second oxidized fine particles in the abrasive grains is lowered, and a sufficient polishing rate cannot be obtained. (3) Preparation of the abrasive and optional components The abrasive of the present invention can be weighed, for example, by the above-mentioned blending amount, and the i-oxide fine particles and the second oxidized fine particles of the above (1), which are required to be formed into a knife. (2) Water and prepared by mixing. In the case where the colloidal silica is used as the SiO2 granules and the second oxidized particles, the colloidal silica is supplied in the state in which the emulsified granules are dispersed in the water in advance. Therefore, the colloidal cerium oxide containing the first cerium oxide fine particles and the colloidal cerium oxide containing the second cerium oxide fine particles can be mixed in a desired ratio and diluted only by appropriate water. The abrasive of the present invention is prepared. Further, the abrasive of the present invention may contain, in addition to the essential components of the above (1) and (2), an abrasive such as a usual chemical mechanical polishing, within the range not impairing the effects of the present invention. Any component contained. (4) Object to be polished The abrasive of the present invention is used for polishing the surface to be polished of the object to be polished, and the object to be polished is not particularly limited. Specifically, a 157409.doc 201213472 glass substrate, a stone wafer, a semiconductor device wiring substrate, and a compound single crystal substrate are exemplified. Among the polishing objects, the abrasive of the present invention can achieve a greater effect in polishing the compound early-crystal substrate, and in particular, it can be used for the modification of the Mohs hardness by a hardness of 10 or more. The substrate is greatly expected to have a higher-speed grinding effect and a long-term stable use effect. Specific examples of the single crystal substrate whose Mohs hardness is corrected on the chest include a sapphire (α-Αΐ2〇3) substrate (hardness: 12), a carbonized stone (four) substrate (hardness: 13), and gallium nitride ( GaN) substrate (hardness: 13) or the like. The abrasive 'in the single crystal substrate' of the present invention is particularly preferably used for the polishing of a sapphire substrate. [Polishing method] As a method of polishing the surface to be polished of the object to be polished by using the polishing agent of the present invention, it is preferable to apply the polishing agent to the polishing pad while polishing the surface of the object to be polished and the polishing pad. Contact and grinding method for grinding by relative motion between the two. In the above polishing method, as the polishing apparatus, a conventionally known polishing apparatus can be used. Fig. 1 shows an example of a polishing apparatus for circulating an abrasive which can be used in the embodiment of the present invention, and will be described below. However, the polishing apparatus used in the embodiment of the present invention is not limited to such a constructor 0 < The apparatus 1 includes a polishing head 2 for holding the object 1 to be polished, a polishing platen 3, a polishing pad 4 bonded to the surface of the polishing platen 3, a storage tank 8 for storing the abrasive 5, and an abrasive. The supply pump 7 supplies the polishing agent 5 to the polishing agent supply pipe polishing device 1 of the polishing pad 4 from the storage tank 8 to form the 157409.doc •10-201213472, while supplying the polishing agent 5 from the polishing agent supply pipe 6 The surface to be polished of the object 1 to be polished held by the polishing head 2 is in contact with the polishing pad 4, and the polishing head 2 is rotated relative to the polishing platen 3 to be polished. With this type of polishing apparatus 10, the polishing of the surface to be polished 1 can be polished. Here, the polishing apparatus 10 is a polishing apparatus that polishes one surface of the object to be polished as a surface to be polished. However, for example, the polishing apparatus 10 may be used to simultaneously polish both surfaces of the polishing pad 10 on the lower surface of the object to be polished. The apparatus grinds the surface to be polished (both sides) of the object to be polished. The polishing head 2 can perform not only a rotary motion but also a linear motion. Further, the polishing platen 3 and the polishing pad 4 may have the same size as or smaller than the object 1 to be polished. In this case, it is preferable that the polishing head 2 and the polishing platen 3 are moved relative to each other to polish the entire surface of the object to be polished. Further, the polishing platen 3 and the polishing pad 4 may not be rotated, and may be unidirectionally moved by a conveyor belt. The polishing conditions of the polishing apparatus 10 are not particularly limited, but the polishing pad 4 may be pressed by applying a load to the polishing head 2 to further increase the polishing pressure to increase the polishing rate. The polishing pressure is preferably 〜5 〇 kpa amp; right ′, but the polishing target 1 is considered to have a polishing surface uniformity, flatness, and scratch prevention such as scratches, and is preferably 1 〇 to 4 〇. Around kPa. The number of revolutions of the polishing platen 3 and the polishing head 2 is preferably about 5 〇 to 5 ,, but is not limited thereto. Further, the amount of the polishing agent 5 to be supplied is appropriately adjusted according to the composition of the surface to be polished or the composition of the polishing agent, the respective polishing conditions, and the like, but is, for example, a wafer having a diameter of 5 mm. 157409.doc • 11 · At 201213472, it is preferably a supply of about 5 to 300 cm3/min. As the polishing crucible 4', a general non-woven fabric, a foamed polyurethane carboxylic acid vinegar, a porous resin, a non-porous resin or the like can be used. Further, in order to promote the supply of the polishing material 5 to the polishing pad 4 or the polishing agent 5 to be accumulated in the polishing crucible 4' in a constant amount, the surface of the polishing pad 4 may be formed in a grid shape or a concentric circular shape. The groove processing can also be carried out by adjusting the surface of the polishing pad 4 while allowing the polishing pad conditioner to contact the surface of the polishing pad 4. Further, the polishing apparatus 1 shown in Fig. 1 includes a recovery unit (not shown) for recovering the polishing agent 5 for polishing from the polishing crucible 4, and is configured to transport the recovered abrasive 5 to the storage tank 8 ^ The polishing agent 5 returned to the storage tank 8 is again supplied to the polishing pad 4 via the abrasive supply pipe 6 by the abrasive supply pump 7. The abrasive 5 is recycled in such a manner. Further, in the polishing method of the present invention, the polishing device which is a so-called flow device, that is, the polishing agent supplied to the polishing pad, may be used in the same manner as described above, but is discarded after each polishing. The composition. The polishing method for recycling the abrasive is preferable because it can reduce the consumption of the abrasive as compared with the polishing method in which the abrasive is discarded after each polishing. However, as the polishing progresses, the components of the workpiece are continuously mixed into the polishing agent due to the polishing. Therefore, in the prior abrasive, there is a tendency to cause aggregation or gelation of the abrasive grains, thereby inducing blockage of the polishing pad. Reduce the problem of grinding speed. According to the abrasive of the present invention, gelation or agglomeration caused by the incorporation of the polishing component due to the above-described grinding is less likely to occur, and 157409.doc 201213472 can suppress a decrease in the polishing rate during recycling. That is, the abrasive of the present invention is characterized in that the initial polishing rate is high and the reduction in the polishing rate when used in a cyclic manner is suppressed. Thereby, not only the efficiency of the polishing step is improved, but also the reduction in the consumption of the abrasive is shortened by the reduction in the frequency of grinding or brushing of the polishing pad, and the reduction in the consumption of the polishing pad. , the grinding step can be effectively carried out 'TM, which is extremely significant for the mass production improvement of various device manufacturing. u EXAMPLES Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the description below. Examples 1 to 6 are examples, and examples 7 to 12 are comparative examples. [Example 1] The concentration of the solid content of the colloidal silica dioxide (4) oxidized stone granules, which has an average primary particle diameter of Ρ 〇 夕 微粒 微粒 微粒 10 10 10 10 10 10 4 4 4 4 4 4 4 4 4 4 4 及 及 及 及 及 及The average-secondary particle size of the oxygen-cut microparticles is: dicolloid dioxotomy (the solid content of the second oxygen-cut microparticles is a wave dispersion / water dispersion). The first oxygen-cut microparticles are at the first! The proportion of the second oxygen-cut microparticles in the total amount of the second oxygen-cut microparticles is adjusted to a ratio of 1, and is sufficiently (4). In the obtained mixed liquid, the first-cut microparticles and the second oxygen-cut microparticles are: The total mass of the abrasive, that is, the first oxygen "fine particles" and the second emulsified fine particles are equal to 0 / square 4, long. The total mass of the water and the water is up to 20 (4) φ ^ + plus ion-exchanged water to prepare an abrasive. In the obtained grinding agent, the 'first oxygen cut micro-rough and the second oxygen cut fine particle system I57409.doc -13· 201213472 components. In the polishing agent obtained in the above-mentioned Example 1, the abrasive particle component containing the cerium oxide microparticles and the second cerium oxide microparticles is an average primary particle diameter and a mixing ratio of each cerium oxide microparticle. Examples and any of the following examples (2 to 12) are also abrasive grain components in the abrasive: water is present in a ratio of 20:80 (mass ratio). Further, the average primary particle size of the cerium oxide microparticles blended in the abrasive is a value obtained by measuring the specific surface area by the nitrogen adsorption BET method. Hereinafter, the average primary particle diameter of the cerium oxide microparticles used in Examples 2 to 12 is a value measured by the same method. [Examples 2 to 12] In the same manner as in Example 1, the table will be! The average primary particle size shown! The cerium oxide fine particles and the second cerium oxide fine particles are blended as the components of the polishing particles as the components shown in Table 2, and further, the total amount of the ith oxidized oxide particles and the second oxidized particles are compared with the abrasive. The polishing agent of Examples 2 to 12 was prepared by adding water so that the ratio of the total mass, that is, the amount of the abrasive component to be 20% by mass. Further, the oxidized cerium particles used are colloidal cerium oxide. [Evaluation] The polishing properties of the abrasives of Examples 1 to 12 obtained above were evaluated by the following methods. As evaluation of polishing characteristics, (1) evaluation of the s-validation of the grinding speed when the polishing agent was used, and (2) the durability of the polishing rate when the polishing agent was recycled. 157409.doc 201213472 <Materials to be polished> In the evaluation of (1) and (2), a 2-inch wafer of a single crystal sapphire substrate (manufactured by Shinko Co., Ltd., (0001) surface, thickness of the substrate of 420 μm) was used. As the object to be polished ^ < polishing method> A table polishing device manufactured by SPEEDFAM Co., Ltd. was used as the polishing device. Use (1) single layer IC1000 K-groove (flow use) and (2) SUBA800-XY-groove (recycling) (both manufactured by NITTA HaaS) as the polishing pad 'use MEC100-PH3.5L before test ( Adjusted by Mitsubishi Materials Corporation) and abrasive brushes. Grinding is to set the supply speed of the abrasive to (1) 1 〇 cm 3 /min (flow use), (2) 100 cm 3 / min (recycling), and the number of revolutions of the grinding platen is set to 100 rpm 'grinding pressure Set to 5 psi or 34 5 kPa, and set the grinding time to (1) 30 minutes (flow use) and (2) 6 〇 minutes (recycle). Further, when the abrasive was recycled, the sapphire substrate was replaced every 6 minutes, and no polishing pad adjustment was performed in the middle, and the polishing was continuously performed. <Grinding speed> The polishing rate was evaluated by the amount of change in thickness (μηι/hr) of the substrate per unit time. Specifically, in the single crystal sapphire substrate used in the above evaluation, the mass of the unpolished substrate having a known thickness and the mass of the substrate after each time of polishing were measured, and the mass change was obtained from the difference, and the mass was calculated by the following formula. The thickness of the substrate obtained by the change varies in every time. (calculation formula of grinding speed (V)) 157409.doc •15· 201213472 △ m=m0 — ml V=Am/m〇xT〇x60/t (wherein, Am(g) represents the mass change before and after grinding, m0 (g) indicates the initial mass of the unpolished substrate, m 1 (g) indicates the mass of the substrate after polishing, V indicates the polishing rate (μπι/hr), T0 indicates the substrate thickness (μηι) of the unpolished substrate, and t indicates the polishing time ( Min)). <Initial polishing rate> First, the polishing agents of Examples 1 to 12 were measured and calculated using the polishing rate under the flow (non-recycling) abrasive conditions as the initial polishing rate in accordance with the above polishing method (1). In addition, the initial polishing rate was found to be a ratio when only the second cerium oxide microparticles having an average primary particle diameter of 80 nm prepared in Example 7 were used as the abrasive of the abrasive grains at an initial polishing rate of 1.00. The results are shown in Table 1. [Table 1] Evaluation Example of Abrasive Particle Composition Evaluation First Colloidal Ceria 2nd Colloidal Ceria Initial Polishing Rate * Average Primary Dispensing Average Average Dispensing Particle Size [nm] [% by mass] Particle size [nm] [Quality %] Example 1 10 1 80 99 1.12 Example 2 10 5 80 95 1.27 Example 3 10 10 80 90 1.24 Example 4 10 25 80 75 1.20 Example 5 17 5 80 95 1.18 Example 6 10 5 54 95 1.15 Example 7 (Comparative Example) 10 0 80 100 1.00 Example 8 (Comparative Example) 10 0.5 80 99.5 1.02 Example 9 (Comparative Example) 10 50 80 50 1.07 Example 10 (Comparative Example) 10 100 80 0 0.94 Example 11 (Comparative Example) 27 10 80 90 1.01 Example 12 (Comparative Example) 10 5 120 95 0.68 * Grinding speed ratio when the polishing rate of Example 7 is 1.00 is 157409.doc • 16 - 201213472 <Persistence of polishing speed> Next, when the abrasive is recycled The durability of the polishing rate was evaluated by the following method. The grinding method follows the method of (2) above. The sapphire substrate is used for the sapphire substrate which is subjected to polishing until the measurement is performed every 60 minutes, and the calculated polishing rate is reduced by 15% compared with the initial polishing rate (the polishing rate of 60 minutes from the start of polishing). The cumulative amount of grinding was evaluated. The cumulative grinding amount of the abrasive of Example 7 was set to 1.00, and the ratio of the durability of the abrasive at the time of recycling was indicated by the ratio. If the number 値 is more than 1.00, it means that the polishing rate is better than that of the polishing agent of Example 7. Here, the term "gel" refers to a type of dispersion, such as a colloid of a liquid dispersion medium such as a sol, but maintains a high viscosity loss fluidity due to a network structure of a dispersoid, so unlike a sol, it becomes a system as a whole. The state of the solid. [Table 2] Example of the composition of the abrasive particles. Evaluation of the first colloidal ceria 2nd colloidal ceria polishing rate ** Average primary particle size [nm] Formulation amount [% by mass] Average primary particle size [nm] [% by mass] Example 1 10 1 80 99 1.09 Example 2 10 5 80 95 1.42 Example 3 10 10 80 90 1.20 Example 4 10 25 80 75 1.08 Example 7 (Comparative Example) 10 0 80 100 1.00 Example 8 (Comparative Example) 10 0.5 80 99.5 1.00 Example 9 (Comparative Example) 10 50 80 50 Gelation Example 10 (Comparative Example) 10 100 1 80 0 Gelation ** The cumulative polishing ratio of the cumulative grinding amount of Example 1.00 was set to 1.00. Doc • 17-201213472 It can be seen from Tables 1 and 2 that the abrasives of the first oxidized particles and the second oxidized particles of the present invention containing the particles of the present invention in the proportion of the present invention are compared with the abrasives of the comparative examples. It is better than the 'grinding speed, λ, and the durability of the polishing speed in use is good, that is, it is excellent in long-term use stability. The present invention has been described in detail and with reference to the specific embodiments thereof, and the various modifications and changes may be added without departing from the scope and spirit of the invention. The present application is based on Japanese Patent Application No. 2010-156536, filed on Jul. INDUSTRIAL APPLICABILITY According to the present invention, a high-hardness compound single crystal substrate such as a polishing object to be polished, in particular, a sapphire (α_Al2〇3) substrate, a carbonized stone (Sic) substrate, or a gallium nitride (GaN) substrate High-speed grinding of the ground surface is possible, and the long-term stability of the abrasive can be improved. Thereby, it is possible to contribute to an increase in the productivity of the substrates. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an example of a polishing apparatus which can be used in the polishing method of the present invention. [Description of main component symbols] 2 3 4 5 Grinding object Grinding head Grinding platen Grinding pad Abrasive 157409.doc • 18 - 201213472 6 Abrasive supply piping 7 Abrasive supply pump 8 Storage tank 10 Grinding device 157409.doc -19-