401648 3505TWF.DOC/006 A7 B7 經濟部中夬標準局負工消費合作社印製 五、發明説明（/ ) 本發明是有關於一種半導體元件的結構與製造方法， 且特別是有關於一種光二極體（photo diode)的結構與製 造方法。 光二極體係利用P-N接合面（P-N junction)，將光能 變換爲電氣信號的半導體受光元件（或稱爲光偵檢元件）。 當沒有光照射之狀態時，因爲P-N接合內部有電場存在， N層中的電子或P層中的電洞，不會向相對層擴散。當具 有足夠能量的光入射時，因爲光能的激發而產生電子-電洞 對，兩者均擴散至接合部。當達到接合部後，由於所存在 之內部電場的作用，電子向N側且電洞向P側分離，進而 積蓄，使P-N接合電極間發生電流。理想上，光二極體在 羁暗之中的作用相當於開路（open circuit)，亦即沒有光 電流的產生。 光二極體元件通常可應用於影像感測器（imagmg sensor)之類的產品，例如PC照相機與數位式照相機（digital camera)等。習知之光二極體通常存在著接合面遺漏電流 (junction leakage current)的缺點，因而造成影像感測器 之產品的暗電流（dark current)過大，同時在營幕顯像時， 容易有不正常之亮點（spot light)發生。 爲了淸楚的說明習知之光二極體所存在缺點，請參照 第1A圖至第ic圖，說明一種習知之光二極體的製造流 程。 請參照第1A圖，在一基底100上，形成一墊氧化(pad oxide)層102,做爲保護基底100表面的犧牲層(sacrifidai 3 (請先閱讀背面之注意事項再填寫本頁) -裝. Φ ,ιτ -線· 本紙張尺度適用中國國家標準（CNS ) Α4規格（210Χ297公釐） 經濟部中央標準局貝工消費合作社印製 401648 3505TWF.DOC/006 A7 B7 五、發明説明（1 ) layer)，例如是以加熱氧化法。然後，於墊氧化層102上， 形成一層已定義的氮化矽（Si3N4)層104a、104b，此氮化 矽層104a與104b主要是用來做爲區域氧化法（local oxidation of silicon ; LOCOS)的罩幕。再進行與基底 100 之P型離子摻質的佈植，透過氮化矽層104a與104b與墊 氧化層102,在基底100的區域進行離子丨#雜。而在後續之 回火（annealing)步驟中，會將前述之P型離子摻雜區往 基底100的底部驅入(drive in)，形成一P井區106。 f 請參照第1B圖，以區域氧化法進行隔離製程，即以濕 式氧化法，在含有水氣的環境中，於P井區106之上的___ 離區形成場氧化（Held oxide ; FOX)層108。 因爲水分子與氧氣不易透過氮化矽層l〇4a與104b，所 以氮化矽所覆蓋處，不會有二氧化矽生成，而其他未被氮 化矽覆蓋的表面，會氧化而形成由二氧化矽所構成的場氧 化層108。然而，水分子與氧氣對氮化砂層104a與104b角 落部份，依然有能力進行水平方向的擴散，因此會形成鳥 嘴區（bird’s beak) 110，亦即位於氮化矽層104a與104b 角落的部份P井區106，仍然會有不同程度的氧化。 請參照第1C圖，以濕式鈾刻法去除氮化矽層104a與 104b，以及P井區106上方所留下來的墊氧化層102。然後， 進行與P井區106之電性相反的離子佈植，先形成一罩幕 層（圖未出示），覆蓋原氮化矽層104b下方之部份P井區 106;接著，在P井區106所暴露出的區域準行N+濃離子摻 :，. 雜。移除此罩幕層後，再形成另一罩幕層（圖未出示），覆 4 表紙裱尺度適用中國圈家標準（CNS ) A4規格（210X297公釐） " (請先閱讀背面之注意事項再填寫本頁)401648 3505TWF.DOC / 006 A7 B7 Printed by the Ministry of Economic Affairs, China Standards Bureau, Bureau of Consumers and Cooperatives. V. Description of the invention (/) The present invention relates to the structure and manufacturing method of a semiconductor element, and in particular to a photodiode (Photo diode) structure and manufacturing method. The photodiode system uses a P-N junction to convert light energy into electrical signals. It is a semiconductor light-receiving element (also called a light detection element). When there is no light irradiation, because there is an electric field inside the P-N junction, the electrons in the N layer or the holes in the P layer will not diffuse to the opposite layer. When light with sufficient energy is incident, electron-hole pairs are generated due to the excitation of the light energy, and both diffuse to the junction. When the junction is reached, due to the effect of the internal electric field, the electrons are separated to the N side and the holes are separated to the P side, and then accumulated, causing a current to flow between the P-N junction electrodes. Ideally, the role of a photodiode in fencing is equivalent to an open circuit, that is, no photocurrent is generated. Photodiode elements are commonly used in products such as image sensors, such as PC cameras and digital cameras. Conventional light diodes usually have the disadvantage of junction leakage current, which causes the dark current of the image sensor product to be too large. At the same time, it is easy to have abnormalities when the screen is displayed. Spot light occurs. In order to explain clearly the shortcomings of the conventional light diode, please refer to FIG. 1A to FIG. Ic to explain a manufacturing process of the conventional light diode. Referring to FIG. 1A, a pad oxide layer 102 is formed on a substrate 100 as a sacrificial layer to protect the surface of the substrate 100 (sacrifidai 3 (please read the precautions on the back before filling this page)- Φ, ιτ -line · This paper size applies to Chinese National Standard (CNS) A4 specification (210 × 297 mm) Printed by the Bayer Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 401648 3505TWF.DOC / 006 A7 B7 V. Description of the invention (1) layer), for example, by a thermal oxidation method. Then, a defined silicon nitride (Si3N4) layer 104a, 104b is formed on the pad oxide layer 102. The silicon nitride layers 104a and 104b are mainly used as a local oxidation of silicon (LOCOS) method. Curtain. Implantation with P-type ions of the substrate 100 is performed, and ions are doped in the region of the substrate 100 through the silicon nitride layers 104a and 104b and the pad oxide layer 102. In the subsequent annealing step, the aforementioned P-type ion-doped region is driven in toward the bottom of the substrate 100 to form a P-well region 106. f Please refer to Figure 1B. The isolation process is carried out by the area oxidation method, that is, the wet oxidation method is used to form a field oxidation (Held oxide; FOX) in the ___ off-zone above the P well zone 106 in an environment containing water vapor. ) Layer 108. Because water molecules and oxygen are not easy to pass through the silicon nitride layers 104a and 104b, silicon dioxide will not be formed where silicon nitride is covered, and other surfaces not covered by silicon nitride will oxidize to form silicon dioxide. A field oxide layer 108 made of silicon oxide. However, water molecules and oxygen still have the ability to diffuse horizontally in the corners of the nitrided sand layers 104a and 104b, so a bird's beak 110 is formed, that is, the corners of the silicon nitride layers 104a and 104b are formed. Part of the P well region 106 will still have varying degrees of oxidation. Referring to FIG. 1C, the silicon nitride layers 104a and 104b and the pad oxide layer 102 left over the P-well region 106 are removed by a wet uranium etching method. Then, an ion implantation opposite to the electrical properties of the P-well region 106 is performed, and a mask layer (not shown) is first formed to cover a part of the P-well region 106 under the original silicon nitride layer 104b; then, in the P-well region 106, The area exposed by the region 106 is quasi-doped with N + concentrated ions. After removing this cover layer, another cover layer is formed (not shown in the figure), covering 4 sheets of paper. The mounting dimensions are applicable to the Chinese circle standard (CNS) A4 specification (210X297 mm) " (Please read the note on the back first (Fill in this page again)
3505TWF.DOC/006 A7 B7_ 五、發明説明（j ) 蓋原氮化矽層104a下方之部份P井區106,再於P井區106 所暴露出的區域進行P+濃離子摻雜。之後，在移除罩幕層 後，進行回火步驟，會將前述之N+濃離子摻雜與P+濃離子 摻雜之部份井區，往P井區106·的底部驅入，形成N+濃離 子摻雜區112與P+濃離子摻雜區114。於是，此N+濃離子 摻雜區112與P井區106的接合面則形成光二極體。 然而，在習知之光二極體元件的結構中，由於場氧化 層108兩側存在著鳥嘴區110，因爲其應力（stress)較大 而產生較多的晶體缺陷（crystal defect)，所以會引起很大 的接合面遺漏電流，進而造成影像感測器之暗電流過大， 而且在螢幕顯像時，容易有不正常之亮點出現。 有鑑於此，本發明的主要目的就是在提供一種光二極 體的結構，用以改善習知之接合面遺瘺電流的缺點，從而 改善傳統式影像感測器之暗電流過大與出現不正常之亮點 的缺點。 依照本發明之一光二極體的結構’形成於一基底之 上，包括：第一導電型的井區，位於基底之上；第一導電 型的摻雜區，位於此井區之上；第二導電型的摻雜區，位 於此井區之上，且與第一導電型的摻雜區於橫向相隔一段 距離；隔離結構層，位於此該井區之上’隔離結構層並不 覆蓋第一導電型的摻雜區，並且隔離結構層於第二導電型 的摻雜區之上方具有一開口，此開口底部與第二導電型的 摻雜區於縱向具有一特定距離。 依照本發明之一光二極體的製造方法，包括下列步 5 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） (請先閲讀背面之注意事項再填寫本頁) •裝·3505TWF.DOC / 006 A7 B7_ V. Description of the invention (j) A portion of the P-well region 106 under the original silicon nitride layer 104a is capped, and P + concentrated ion doping is performed on the area exposed by the P-well region 106. After that, after the mask layer is removed, a tempering step is performed, which drives the aforementioned well regions doped with N + concentrated ions and P + concentrated ions into the bottom of P well region 106 · to form N + concentrated The ion doped region 112 and the P + concentrated ion doped region 114. Therefore, the junction surface of the N + concentrated ion doped region 112 and the P well region 106 forms a photodiode. However, in the structure of the conventional photodiode element, since the bird's beak region 110 exists on both sides of the field oxide layer 108, it causes a large number of crystal defects due to its large stress, which will cause The large leakage current on the joint surface causes the dark current of the image sensor to be too large, and abnormal bright spots are easy to appear when the screen is displayed. In view of this, the main purpose of the present invention is to provide a photodiode structure to improve the shortcomings of the conventional junctional fistula current, thereby improving the excessive dark current and abnormal bright spots of the conventional image sensor. Shortcomings. A photodiode structure according to the present invention is formed on a substrate and includes: a well region of a first conductivity type located on the substrate; a doped region of the first conductivity type located on the well region; A two-conductivity type doped region is located above this well region and is laterally separated from the first conductivity-type doped region; an isolation structure layer is located above this well region. The 'isolation structure layer does not cover the first A conductive type doped region, and the isolation structure layer has an opening above the second conductive type doped region, and the bottom of the opening and the second conductive type doped region have a specific distance in the longitudinal direction. A method of manufacturing a photodiode according to the present invention includes the following steps. 5 This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) (Please read the precautions on the back before filling this page).
、1T 線 -© 經濟部中央標準局員工消費合作社印製 經濟部中央標準局員工消費合作社印製 401648 3505TWF.DOC/006 A7 _ B7 __________ 五、發明説明（4 ) 驟：提供一基底，其上至少包括一井區；形成隔離層於此 井區上；以隔離層做爲罩幕，形成第一離子摻雜區於井區 上；形成已定義的罩幕層於隔離層上，並覆蓋第一離子摻 雜區；蝕刻隔離區，以形成一開口；以及以罩幕層和隔離 層做爲罩幕’於此開口下方之井區上，形成一第二離子摻 雜區。爲讓本發明之上述目的、特徵 '和優點能更明顯易 懂，下文特舉一較佳實施例，並配合所附圖式，作詳細說 明如下： 圖式之簡卓g兌明： 第1A圖至第1C圖係繪示傳統式光二極體的製造流程 剖面示意圖；以及 第2A圖至第2G圖係繪示根據本發明之一較佳實施 例，一種光二極體的製造流程剖面示意圖。 圖式之標記說明： 100、200 :基底 102、202 :墊氧化層 104a、104b、204 :氮化矽層 106、206 : P 井區 108、208 :場氧化層 110、210 :鳥嘴區 112、222 : N+濃離子摻雜區 114 : P+濃離子摻雜區 212 : P+濃離子摻雜區 214 :光阻 6 ^紙張尺度適用^國國家標準（CNS ) A4規格（210X297公楚1 " (請先閱讀背面之注意事項再填寫本頁) .裝- 訂 線 401648 經濟部中央標準局貝工消費合作社印製 3505TWF.DOC/006 A7 B7 五、發明説明（夕） 216 :光阻開口 218 :接觸窗口 220 :剩餘氧化層的厚度 實施例 第2A圖至第2G圖係繪示根據本發明之一較佳實施 例，一種光二極體之製造流程的剖面示意圖。 請參照第2A圖，在基底200上，形成一墊氧化層202， 做爲保護基底200表面以減少離子植入時之破壞的會牲 層，例如是以加熱氧化法形成墊氧化層202。然後，在基 底200之上進行P型離子摻質的佈植，透過墊氧化層202， 而在基底200的區域進行離子摻雜。在後續之回火步驟 中，會將前述之P型離子摻雜區往基底200的底部驅入， 形成一P井區206。 請參照第2B圖，於墊氧化層202上，形成一層已定義 的氮化矽層2〇4，此氮化矽層204主要是用來做爲區 域氧化法（LOCOS)的罩幕。 請參照第2C圖，接著，以區域氧化法進行隔離製程， 即以—式氧化法，在含有水氣的環境中，於P井區206之 上形成場氧化（FOX)層208。而在氮化矽層204角落的部 份P井區206，會形成鳥嘴區210。 請參照第2D圖，以濕式鈾刻法去除氮化矽層204與部 份墊氧化層202。然後，在P井區206所暴露出的區域進行 P+濃離子摻雜，形成P+濃離子摻雜區212。此步驟所使用的 摻雜離子二例如是硼(B)、氟化硼（BF2)等，離子植入的能量 7 本^張尺度中國國家標準（CNS ) A4規格（210X297公ϋ (請先閱讀背面之注意事項再填寫本頁) .裝. 、1Τ 、線 4Q1648 3505TWF.DOC/006 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明（石） 約爲30〜560KeV，離子植入的劑量約爲1〇|2~1016/〇112，離子 植入的傾角（tilt angle)小於60° 。 請參照第2E圖，然後，在基底200上形成已定義的光 阻層214，以做爲罩幕之用，或是其他可做爲阻擋後續之 離子摻雜步驟的材料層，使其覆蓋P+濃離子摻雜區212。 其中光阻層214圖案中，具有一光阻開口 216，以暴露出部 份的場氧化層208。 請參照第2F圖，再以鈾刻法定義場氧化層208，以形 成接觸窗口 218，.例如是以非等向性鈾刻法；或者，亦可 先使用濕鈾刻法，然後再使用乾蝕刻法。最重要的是，在 經非等向性蝕刻法之均勻蝕刻後，接觸窗口 218的底部至P 井區206表面，仍保留一剩餘氧化層的厚度220，約小於 3000 A，可做爲後續之離子摻雜步驟時，防止P井區206 之表面受電獎的損傷(plasma damage)。 請參照第2G圖，進行與P井區206電性相反的離子佈 植，即在接觸窗口 218所暴露出的區域進行N+濃離子摻 雜，形成N+濃離子摻雜區222,此N+濃離子摻雜區222與P 井區206的接合面則形成光二極體。此步驟所使用的摻雜 離子，例如是砷（As)、磷（P)等，離子植入的能量約爲 30〜560KeV，離子植入的劑量約爲1012〜l(V6/cm2，離子植入 的傾角小於60° 。然而此後續之製程爲熟習此技藝者所熟 知，且非關本發明之特徵，故此處不再贅述。 依照本發明之一較佳實施例，藉由場氧化層208之接 觸窗口 218，進行N+濃離子摻雜，因此，N+濃離子摻雜區 8 $ -•9 韜 (請先閱讀背面之注意事項再填寫本頁)Line 1T-© Printed by the Consumers 'Cooperative of the Central Standards Bureau of the Ministry of Economics Printed by the Consumers' Cooperative of the Central Standards Bureau of the Ministry of Economics 401648 3505TWF.DOC / 006 A7 _ B7 __________ 5. Description of the Invention: Provide a base on which At least one well region is formed; an isolation layer is formed on the well region; the isolation layer is used as a mask to form a first ion-doped region on the well region; a defined mask layer is formed on the isolation layer and covers the first An ion-doped region; etching the isolation region to form an opening; and using the mask layer and the isolation layer as a mask to form a second ion-doped region on the well region below the opening. In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is given below in conjunction with the accompanying drawings to make a detailed description as follows: The simplicity of the drawings is clear: Section 1A Figures 1 to 1C are schematic cross-sectional views of a manufacturing process of a conventional photodiode; and Figures 2A to 2G are schematic cross-sectional views of a manufacturing process of a photodiode according to a preferred embodiment of the present invention. Symbols of the drawings: 100, 200: substrates 102, 202: pad oxide layers 104a, 104b, 204: silicon nitride layers 106, 206: P well regions 108, 208: field oxide layers 110, 210: bird's beak region 112 222: N + concentrated ion doped region 114: P + concentrated ion doped region 212: P + concentrated ion doped region 214: photoresist 6 ^ Paper size applies ^ National Standard (CNS) A4 specification (210X297 Gong Chu 1 " (Please read the precautions on the back before filling this page). Installation-Thread 401648 Printed by the Central Laboratories of the Ministry of Economic Affairs, Shellfish Consumer Cooperative, 3505TWF.DOC / 006 A7 B7 V. Description of the invention (Evening) 216: Photoresistive opening 218 : Contact window 220: Thickness of remaining oxide layer Embodiments 2A to 2G are schematic cross-sectional views illustrating a manufacturing process of a photodiode according to a preferred embodiment of the present invention. Please refer to FIG. 2A, On the substrate 200, a pad oxide layer 202 is formed as a meeting layer for protecting the surface of the substrate 200 to reduce the damage during ion implantation. For example, the pad oxide layer 202 is formed by a thermal oxidation method. Then, the pad oxide layer 202 is formed on the substrate 200. The implantation of P-type ion dopants passes through the pad oxide layer 202, and The region of the substrate 200 is ion-doped. In the subsequent tempering step, the aforementioned P-type ion-doped region is driven toward the bottom of the substrate 200 to form a P-well region 206. Please refer to FIG. 2B, for the pad On the oxide layer 202, a defined silicon nitride layer 204 is formed, and the silicon nitride layer 204 is mainly used as a mask for the LOCOS method. Please refer to FIG. 2C, and then use the area The oxidation method performs an isolation process, that is, a field oxidation method is used to form a field oxide (FOX) layer 208 on the P-well region 206 in an environment containing water and gas, and a part of the P-well in the corner of the silicon nitride layer 204 The region 206 will form the bird's beak region 210. Please refer to Figure 2D to remove the silicon nitride layer 204 and part of the pad oxide layer 202 by a wet uranium etching method. Then, perform P + on the area exposed by the P-well region 206 Concentrated ion doping to form a P + concentrated ion doped region 212. The doped ions used in this step are, for example, boron (B), boron fluoride (BF2), etc., and the energy of ion implantation 7 Standard (CNS) A4 specification (210X297 males (please read the precautions on the back before filling out this page). Install., 1T, cable 4Q1648 3505TWF.DOC / 006 A7 B7 printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 5. Description of the invention (stone) is about 30 ~ 560KeV, the dose of ion implantation is about 10 | 2 ~ 1016 / 〇112, ion implantation The tilt angle is less than 60 °. Please refer to FIG. 2E. Then, a defined photoresist layer 214 is formed on the substrate 200 for use as a mask or other material layer that can block subsequent ion doping steps to cover P +. Concentrated ion doped region 212. The photoresist layer 214 has a photoresist opening 216 in the pattern to expose a portion of the field oxide layer 208. Please refer to FIG. 2F, and then define the field oxide layer 208 by the uranium etching method to form the contact window 218, for example, using an anisotropic uranium etching method; Etching. The most important thing is that after uniform etching by anisotropic etching, the bottom of the contact window 218 to the surface of the P-well region 206 still has a residual oxide thickness of 220, less than about 3000 A, which can be used as a follow-up During the ion doping step, the surface of the P-well region 206 is protected from plasma damage. Referring to FIG. 2G, ion implantation is performed opposite to that of the P-well region 206, that is, N + concentrated ion doping is performed in the area exposed by the contact window 218 to form an N + concentrated ion doped region 222. This N + concentrated ion The junction between the doped region 222 and the P-well region 206 forms a photodiode. The doped ions used in this step are, for example, arsenic (As), phosphorus (P), etc. The energy of ion implantation is about 30 ~ 560KeV, and the dose of ion implantation is about 1012 ~ l (V6 / cm2, ion implantation). The inclination angle is less than 60 °. However, this subsequent process is well known to those skilled in the art and is not related to the features of the present invention, so it will not be repeated here. According to a preferred embodiment of the present invention, the field oxide layer 208 is used. The contact window 218 is doped with N + concentrated ions. Therefore, the N + concentrated ion doped region is 8 $-• 9 Tao (Please read the precautions on the back before filling this page)
本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 經濟部中央標準局員工消費合作社印製 401648 3505TWF.DOC/006 A7 ___B7 _ . 五、發％説明（'7 ) 222遠籬鳥嘴區210，藉此降低接面遺漏電流。此外，本發 明在形成P井區206時，僅以墊氧化層202保護基底200 表面，無須穿過氮化砂層204。 另一方面，本發明利用光阻層214與場氧化層208，共 同做爲罩幕之用，能使接觸窗口 218的底部至P井區206 表面之一薄層氧化政的可調性提高，使剩餘氧化層的厚度 220低於3Q00 A。以及，在進行N+濃離子摻雜時，不論摻 雜離子的種類.、離子植入的能量、離子植入的劑量與甚至 晶片和入射離子束的傾角，均具有很高的調變性;，而不影 響其他的元件區。 .. 綜上所述，本發明的特徵在於： 1. 依照本發明之一較佳實施例，在形成P井區時，僅 以墊氧化層保護基底表面，無須穿過氮化矽層。 2. 本發明在場氧化層之接觸窗口，進行N+濃離子ί參 雜’使得Ν+濃離子摻雜區遠離鳥嘴區，藉此降低接面遺漏 電流。 3. 在本發明中，經非等向性蝕刻法之均勻蝕刻後，接 觸窗口的底部至Ρ井區表面，仍保留二氧化矽薄層，厚度 低於3000 A，可做爲後續之離子摻雜步驟時，防止ρ井區 之表面受電漿的損傷。 4. 本發明利用光阻層與場氧化層，共同做爲罩幕之 用，能使接觸窗口的底部至P井區表面之二氧化砂薄層的 可調性提高。此外，在進行N+濃離子摻雜時，·不論摻雜離 子的種類、離子植入的能量、離子植入的劑量與甚至晶片 9 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐i ' ~ —l· —------裝------訂-----丨線 (請先閲讀背面之注意事項再填寫本頁)This paper size applies to China National Standard (CNS) A4 (210X297 mm) Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 401648 3505TWF.DOC / 006 A7 ___B7 _. V. Percentage Instructions ('7) 222 Farrowing Bird The mouth region 210, thereby reducing the interface leakage current. In addition, when the P-well region 206 is formed in the present invention, only the pad oxide layer 202 is used to protect the surface of the substrate 200 without passing through the nitrided sand layer 204. On the other hand, in the present invention, the photoresist layer 214 and the field oxide layer 208 are used together as a mask, which can improve the adjustability of a thin layer of oxide on the bottom of the contact window 218 to the surface of the P-well region 206. Keep the thickness of the remaining oxide layer 220 below 3Q00 A. And, when N + concentrated ion doping is performed, regardless of the type of doped ions, the energy of ion implantation, the dose of ion implantation, and even the tilt angle of the wafer and the incident ion beam, all have high modulation properties; and Does not affect other component areas. ... In summary, the present invention is characterized in that: 1. According to a preferred embodiment of the present invention, when forming a P-well region, only the pad oxide layer is used to protect the surface of the substrate without having to pass through the silicon nitride layer. 2. In the contact window of the field oxide layer of the present invention, N + concentrated ions are doped 'so that the N + concentrated ion doped region is far from the bird's beak region, thereby reducing the leakage current at the interface. 3. In the present invention, after the uniform etching by the anisotropic etching method, the bottom of the contact window to the surface of the P-well region, a thin layer of silicon dioxide remains, and the thickness is less than 3000 A, which can be used as a subsequent ion doping. In the complicated step, the surface of the ρ well area is prevented from being damaged by the plasma. 4. The present invention uses a photoresist layer and a field oxide layer together as a mask, which can improve the adjustability of the thin layer of sand dioxide on the bottom of the contact window to the surface of the P-well area. In addition, when doping N + concentrated ions, regardless of the type of doped ions, the energy of ion implantation, the dose of ion implantation, and even the wafer 9 This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) i '~ --l · -------- install ------ order ----- 丨 line (please read the precautions on the back before filling this page)
3505TWF.DOC/006 A7 B7 經濟部中央標準局員工消費合作社印製 五、發明説明（公） 和入射離子束的傾角，均具有很高的調變性’而不影饗其 他的元件區。 雖然本發明已以一較佳實施例揭露如上’然其並非用 以限定本發明，任何熟習此技藝者，在不脫離本發明之精 神和範圍內，當可作各種之更動與潤飾，因此本發明之保 5蒦箪13圍當視後附之申請專利範圍所界定者爲準。 本紙張尺度適用中國國家標準（CMS ) A4規格（210X297公釐〉 *澤· -a (請先閲讀背面之注意事項再填寫本頁)3505TWF.DOC / 006 A7 B7 Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 5. The invention description (male) and the inclination of the incident ion beam have a high degree of modulation ’without affecting the other component areas. Although the present invention has been disclosed above in a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and decorations without departing from the spirit and scope of the present invention. The guarantee of invention 5 蒦 箪 13 is subject to the definition of the scope of patent application attached. This paper size applies the Chinese National Standard (CMS) A4 specification (210X297mm> * Ze · -a (Please read the precautions on the back before filling this page)