JP4751865B2 - Back-illuminated solid-state imaging device and manufacturing method thereof - Google Patents

Back-illuminated solid-state imaging device and manufacturing method thereof Download PDF

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JP4751865B2
JP4751865B2 JP2007233960A JP2007233960A JP4751865B2 JP 4751865 B2 JP4751865 B2 JP 4751865B2 JP 2007233960 A JP2007233960 A JP 2007233960A JP 2007233960 A JP2007233960 A JP 2007233960A JP 4751865 B2 JP4751865 B2 JP 4751865B2
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shielding member
light shielding
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周 高橋
雄二 伊藤
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Fujifilm Corp
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Description

本発明は裏面照射型固体撮像素子及びその製造方法に係り、特に、画素間のクロストークや混色等を好適に回避することができる裏面照射型固体撮像素子及びその製造方法に関する。   The present invention relates to a back-illuminated solid-state imaging device and a manufacturing method thereof, and more particularly to a back-illuminated solid-state imaging device and a manufacturing method thereof that can suitably avoid crosstalk and color mixing between pixels.

ＣＭＯＳイメージセンサやＣＣＤイメージセンサ等の固体撮像素子には、表面照射型と裏面照射型がある。イメージセンサの主要電子素子である信号読出回路（ＣＭＯＳイメージセンサであればトランジスタ回路及び配線層，ＣＣＤイメージセンサであれば配線を含む電荷転送路）が形成された半導体基板の一面側（この面を「表面側」ということにする。）と同一面で、被写体からの入射光を受光する構造になっているものが表面照射型である。   Solid-state imaging devices such as a CMOS image sensor and a CCD image sensor include a front side illumination type and a back side illumination type. One side of a semiconductor substrate on which a signal readout circuit (a transistor circuit and wiring layer for a CMOS image sensor, a charge transfer path including wiring for a CCD image sensor), which is a main electronic element of an image sensor, is formed (this surface is The surface irradiation type is the same plane as “front side” and has a structure for receiving incident light from a subject.

これに対し、裏面照射型とは、例えば下記特許文献１に記載されている様に、信号読出回路が形成された半導体基板表面側と反対側の面（＝裏面）で被写体からの入射光を受光する構造のものをいう。   On the other hand, the back-illuminated type, as described in, for example, Patent Document 1 below, receives incident light from a subject on a surface (= back surface) opposite to the front surface side of the semiconductor substrate on which the signal readout circuit is formed. A structure that receives light.

即ち、裏面照射型固体撮像素子は、半導体基板の表面側に多数のフォトダイオードが二次元アレイ状に形成されると共に各フォトダイオードが検出した撮像画像信号を読み出す信号読出回路が形成され、裏面側に、カラーフィルタやマイクロレンズが形成され、裏面側から半導体基板内に入射した光によって発生した光電荷を表面側のフォトダイオードで捕らえ、信号読出回路がこの光電荷を出力する構成になっている。   That is, the backside illumination type solid-state imaging device has a number of photodiodes formed in a two-dimensional array on the front side of the semiconductor substrate and a signal readout circuit that reads out the captured image signal detected by each photodiode. In addition, a color filter and a microlens are formed, and the photocharge generated by the light incident on the semiconductor substrate from the back side is captured by the photodiode on the front side, and the signal readout circuit outputs this photocharge. .

この裏面照射型は、信号読出回路を裏面側に設ける必要がないため開口率を大きくとることができ、また、半導体基板の厚さを厚くできるため入射光エネルギの殆ど全てを光電変換でき、高感度であるという利点がある。   This back-illuminated type can increase the aperture ratio because there is no need to provide a signal readout circuit on the back side, and can increase the thickness of the semiconductor substrate, so that almost all of the incident light energy can be photoelectrically converted. There is an advantage of sensitivity.

特開２００６―８０４５７号公報JP 2006-80457 A

裏面照射型固体撮像素子は、裏面側から入射した被写界光を、表側のフォトダイオードが受光する構成のため、各フォトダイオード毎に設けられるカラーフィルタやマイクロレンズが当該フォトダイオードに整列して形成されていないと、斜め入射光が隣接画素（フォトダイオード）に入り、クロストークや混色等が発生してしまう。   The back-illuminated solid-state imaging device has a configuration in which the front-side photodiode receives the field light incident from the back side, so that color filters and microlenses provided for each photodiode are aligned with the photodiode. If not formed, obliquely incident light enters adjacent pixels (photodiodes), and crosstalk, color mixing, and the like occur.

しかし、カラーフィルタやマイクロレンズをフォトダイオードに整列させて形成しても、裏面照射型固体撮像素子では、光電変換効率を高めるために半導体基板が厚く光路長が長くなっているため、斜め入射光が隣接画素に入ってしまうという問題がある。   However, even if the color filters and microlenses are aligned with the photodiode, the back-illuminated solid-state image sensor has a thick semiconductor substrate and a long optical path length to increase the photoelectric conversion efficiency. There is a problem that enters the adjacent pixels.

特許文献１記載の従来技術では、半導体基板のマイクロレンズ直下を画素毎に広くエッチングで削ることで画素毎に凹所を形成し、この凹所の内周面に反射膜を形成することで、マイクロレンズで集光された光を全て該当のフォトダイオードに入射させる構成になっている。   In the prior art described in Patent Document 1, by forming a recess for each pixel by etching a wide area directly under the microlens of the semiconductor substrate for each pixel, and forming a reflective film on the inner peripheral surface of this recess, All the light condensed by the microlens is incident on the corresponding photodiode.

しかし、この従来技術では、凹所の中を透明絶縁層で埋めているため、この凹所内が光電変換に寄与することがなく、裏面照射型の利点を犠牲にして混色防止を図っている。   However, in this prior art, since the inside of the recess is filled with a transparent insulating layer, the inside of the recess does not contribute to photoelectric conversion, and color mixing is prevented at the expense of the advantage of the backside illumination type.

本発明の目的は、斜め入射光の隣接画素への進入を好適に抑制することができしかも光電変換効率の高い裏面照射型固体撮像素子及びその製造方法を提供することにある。   An object of the present invention is to provide a back-illuminated solid-state imaging device that can suitably suppress the entrance of obliquely incident light into adjacent pixels and has high photoelectric conversion efficiency, and a method for manufacturing the same.

本発明の裏面照射型固体撮像素子は、半導体基板と、該半導体基板の表面側に二次元アレイ状に形成され該半導体基板の裏面側から入射した光によって光電変換された信号電荷を蓄積する複数のフォトダイオードと、前記裏面側に形成され前記光電変換により前記信号電荷と対で発生する電荷を引き寄せる高濃度不純物層と、該高濃度不純物層が隣接フォトダイオード間で少なくとも一部が連続するように該高濃度不純物層に埋設され前記各フォトダイオードへの入射光を隣接する前記フォトダイオードから区画する遮光部材とを備えることを特徴とする。 A backside illumination type solid-state imaging device according to the present invention includes a semiconductor substrate and a plurality of signal charges formed in a two-dimensional array on the surface side of the semiconductor substrate and photoelectrically converted by light incident from the back side of the semiconductor substrate. A high-concentration impurity layer that is formed on the back surface side and attracts charges generated in pairs with the signal charges by the photoelectric conversion, and the high-concentration impurity layer is at least partially continuous between adjacent photodiodes. And a light shielding member that is embedded in the high-concentration impurity layer and partitions incident light on each photodiode from the adjacent photodiode.

本発明の裏面照射型固体撮像素子の製造方法は、表面側に複数のフォトダイオードが二次元アレイ状に形成され、裏面側から入射した光によって光電変換された信号電荷が前記フォトダイオードに蓄積される半導体基板の前記裏面側に、前記光電変換により前記信号電荷と対で発生する電荷を引き寄せる高濃度不純物層を形成し、該裏面のうち、前記各フォトダイオードへの入射光を隣接する前記フォトダイオードから区画する境界位置をエッチングにより削り、該境界位置の前記高濃度不純物層に、該高濃度不純物層が隣接フォトダイオード間で少なくとも一部が連続するように遮光材料を埋設することを特徴とする。 In the manufacturing method of the backside illumination type solid-state imaging device of the present invention, a plurality of photodiodes are formed in a two-dimensional array on the front side, and signal charges photoelectrically converted by light incident from the back side are accumulated in the photodiodes. Forming a high-concentration impurity layer on the back side of the semiconductor substrate that attracts the charge generated in pairs with the signal charge by the photoelectric conversion; A boundary position partitioned from the diode is cut by etching, and a light shielding material is embedded in the high concentration impurity layer at the boundary position so that the high concentration impurity layer is at least partially continuous between adjacent photodiodes. To do.

本発明の裏面照射型固体撮像素子の製造方法は、前記遮光部材が導電性材料で形成され、該遮光部材が前記高濃度不純物層内に絶縁膜を被覆した状態で埋設されることを特徴とする。   The method for manufacturing a backside illumination type solid-state imaging device according to the present invention is characterized in that the light shielding member is formed of a conductive material, and the light shielding member is embedded with an insulating film covered in the high concentration impurity layer. To do.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記遮光部材は導電性材料で形成され、前記高濃度不純物層に直接接触する前記遮光部材は該高濃度不純物層を突き抜けて形成されることを特徴とする。 Back-illuminated solid-state imaging device and its manufacturing method of the present invention, the light blocking member is formed of a conductive material, the light blocking member in direct contact with the high concentration impurity layer is formed by penetrating the said high concentration impurity layer It is characterized by that.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記遮光部材の埋め込み深さが前記高濃度不純物層を突き抜けて形成され、該遮光部材には、光の入射方向に該遮光部材の分断部が生じないようにして隣接画素間で前記高濃度不純物層を連続させる一部欠損部が設けられることを特徴とする。 The back-illuminated solid-state imaging device and the method of manufacturing the same according to the present invention are such that the light-shielding member is embedded in a depth of penetration through the high-concentration impurity layer, and the light-shielding member is divided in the light incident direction. It is characterized in that a partial deficient portion is provided in which the high-concentration impurity layer is continued between adjacent pixels so that no portion is generated .

本発明の裏面照射型固体撮像素子及びその製造方法は、前記遮光部材が、前記裏面側から突出して形成されることを特徴とする。   The backside illumination type solid-state imaging device and the manufacturing method thereof according to the present invention are characterized in that the light shielding member is formed to protrude from the backside.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記裏面側の表面に絶縁膜と反射防止膜とが形成されることを特徴とする。   The backside illuminated solid-state imaging device and the manufacturing method thereof according to the present invention are characterized in that an insulating film and an antireflection film are formed on the surface on the backside.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記反射防止膜が前記遮光部材によって分断されることを特徴とする。   The backside illumination type solid-state imaging device and the manufacturing method thereof according to the present invention are characterized in that the antireflection film is divided by the light shielding member.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記遮光部材の前記裏面側先端部が先細に形成されることを特徴とする。   The backside illumination type solid-state imaging device and the method of manufacturing the same according to the present invention are characterized in that the tip of the backside of the light shielding member is tapered.

本発明の裏面照射型固体撮像素子は、前記遮光部材に所定電圧が印加されることを特徴とする。   In the backside illumination type solid-state imaging device of the present invention, a predetermined voltage is applied to the light shielding member.

本発明の裏面照射型固体撮像素子及びその製造方法は、前記所定電圧を印加する回路が前記半導体基板の周辺部に設けられることを特徴とする。   The back-illuminated solid-state imaging device and the manufacturing method thereof according to the present invention are characterized in that a circuit for applying the predetermined voltage is provided in a peripheral portion of the semiconductor substrate.

本発明によれば、裏面画素の画素区画部に設ける遮光部材を半導体基板に埋設することで形成するため、光入射方向に長さの長い遮光部材を形成することができ、遮光性能の向上を図ることが可能となる。また、本発明では、半導体基板の光電変換領域となる部分を厚さ方向に削ることはしないため、高い光電変換率を得ることができる。   According to the present invention, since the light shielding member provided in the pixel partition portion of the back surface pixel is embedded in the semiconductor substrate, the light shielding member having a long length in the light incident direction can be formed, and the light shielding performance is improved. It becomes possible to plan. Moreover, in this invention, since the part used as the photoelectric conversion area | region of a semiconductor substrate is not shaved in the thickness direction, a high photoelectric conversion rate can be obtained.

以下、本発明の一実施形態について、図面を参照して説明する。   Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

図１は、本発明の一実施形態に係る裏面照射型固体撮像素子１００の断面模式図である。本実施形態の固体撮像素子はインターライン型ＣＣＤであり、ｐ型半導体基板１の表面側に垂直電荷転送路（ＶＣＣＤ）２１とフォトダイオード（光電変換素子）２２とが形成され、裏面側に、カラーフィルタ（赤（Ｒ），緑（Ｇ），青（Ｂ））層２３及びマイクロレンズ２４が積層される。   FIG. 1 is a schematic cross-sectional view of a backside illumination type solid-state imaging device 100 according to an embodiment of the present invention. The solid-state imaging device of this embodiment is an interline CCD, and a vertical charge transfer path (VCCD) 21 and a photodiode (photoelectric conversion device) 22 are formed on the front surface side of the p-type semiconductor substrate 1, and on the back surface side. A color filter (red (R), green (G), blue (B)) layer 23 and a microlens 24 are laminated.

各色カラーフィルタ２３は対応するフォトダイオード２２に整列する位置に積層され、また、各マイクロレンズ２４は、対応するフォトダイオード２２の中心に焦点が合うようにフォトダイオード２２に整列して形成される。   Each color filter 23 is stacked at a position aligned with the corresponding photodiode 22, and each microlens 24 is formed aligned with the photodiode 22 so as to be focused on the center of the corresponding photodiode 22.

尚、本実施形態の裏面照射型固体撮像素子１００はＣＣＤタイプであるが、特許文献１記載の様なＣＭＯＳタイプその他の形式の固体撮像素子にも本実施形態を同様に適用できる。   Although the backside illumination type solid-state imaging device 100 of this embodiment is a CCD type, the present embodiment can be similarly applied to a CMOS type or other type of solid-state imaging device as described in Patent Document 1.

半導体基板１の裏面側表面部には高濃度ｐ層（ｐ＋＋層）２５が形成され、このｐ層２５が接地される。高濃度ｐ層２５の上には入射光に対して透明な絶縁層（例えば酸化膜）２６が積層され、その上に、窒化シリコンやダイヤモンド構造炭素膜等の入射光に対して透明な高屈折率層２７が反射防止膜として積層され、その上に、カラーフィルタ層２３，マイクロレンズ（トップレンズ）層２４が順に積層される。 A high-concentration p layer (p ++ layer) 25 is formed on the rear surface side surface portion of the semiconductor substrate 1, and the p layer 25 is grounded. An insulating layer (for example, an oxide film) 26 that is transparent to incident light is laminated on the high-concentration p layer 25, and a high refractive index that is transparent to incident light such as silicon nitride or a diamond structure carbon film is formed thereon. The rate layer 27 is stacked as an antireflection film, and the color filter layer 23 and the microlens (top lens) layer 24 are sequentially stacked thereon.

カラーフィルタ層２３は画素（フォトダイオード）単位に区画され、カラーフィルタ層２３の半導体基板１側の隣接区画間には、詳細は後述する遮光部材２８が設けられる。この遮光部材２８は、斜め入射光が隣接画素に進入するのを防止するために設けられ、タングステン膜やアルミニウム膜等で遮光部材への入射光を反射する構成のものや、遮光部材への入射光を吸収する材料で形成する（本実施形態では、タングステン膜とする。）。   The color filter layer 23 is partitioned in units of pixels (photodiodes), and a light shielding member 28 described later in detail is provided between adjacent partitions on the semiconductor substrate 1 side of the color filter layer 23. The light shielding member 28 is provided to prevent obliquely incident light from entering adjacent pixels, and is configured to reflect incident light on the light shielding member with a tungsten film, an aluminum film, or the like, or incident on the light shielding member. It is formed of a material that absorbs light (in this embodiment, a tungsten film is used).

図２は、遮光部材２８を裏面側から見た状態を示す図であり、全体として網目状に形成され、各網目が１画素１画素を区画する。この遮光部材２８を設けることにより、単板式カラー画像撮像用固体撮像素子では、異なる色を検出する隣接画素間の混色が抑制され、多板式カラー画像撮像用固体撮像素子では、同色の信号を検出する隣接画素間のクロストークが抑制される。   FIG. 2 is a diagram showing a state in which the light shielding member 28 is viewed from the back side, and is formed in a mesh shape as a whole, and each mesh defines one pixel and one pixel. By providing this light shielding member 28, in the solid-state image pickup device for color image pickup of a single plate, color mixing between adjacent pixels that detect different colors is suppressed, and in the solid-state image pickup device for color pickup of a multi-plate color image, signals of the same color are detected. Crosstalk between adjacent pixels is suppressed.

半導体基板１の表面側に形成される垂直電荷転送路（ＶＣＣＤ）２１は、高濃度ｎ層の埋め込みチャネル３１と、半導体基板１の表面側最表面に形成されたシリコン酸化膜やＯＮＯ（酸化膜―窒化膜―酸化膜）構造の絶縁膜でなるゲート絶縁層３２を介して積層された転送電極膜３３とで構成される。   A vertical charge transfer path (VCCD) 21 formed on the front surface side of the semiconductor substrate 1 includes a buried channel 31 of a high concentration n layer and a silicon oxide film or ONO (oxide film) formed on the outermost surface side of the semiconductor substrate 1. (Transfer electrode film 33) laminated with a gate insulating layer 32 made of an insulating film of (nitride film-oxide film) structure.

垂直電荷転送路２１は、図示しない水平電荷転送路（ＨＣＣＤ）が延びる方向に対して垂直方向に延びる様に形成され、且つ、複数本の垂直電荷転送路２１が形成される。そして、隣接する垂直電荷転送路２１間に、垂直電荷転送路２１に沿う方向に複数のフォトダイオード２２が所定ピッチで形成される。   The vertical charge transfer path 21 is formed so as to extend in a direction perpendicular to a direction in which a horizontal charge transfer path (HCCD) (not shown) extends, and a plurality of vertical charge transfer paths 21 are formed. A plurality of photodiodes 22 are formed between adjacent vertical charge transfer paths 21 in a direction along the vertical charge transfer path 21 at a predetermined pitch.

フォトダイオード２２は、本実施形態では、ｐ型半導体基板１の表面側に形成されたｎ層３５とその下に形成されたｎ−層３６とで構成される。そして、ｎ層３５の表面部に暗電流抑制用の薄いｐ型高濃度表面層３８が形成され、表面層３８の中央表面部に、コンタクト部としてｎ＋層３９が形成される。 In this embodiment, the photodiode 22 includes an n layer 35 formed on the surface side of the p-type semiconductor substrate 1 and an n − layer 36 formed thereunder. A thin p-type high-concentration surface layer 38 for suppressing dark current is formed on the surface portion of the n layer 35, and an n + layer 39 is formed as a contact portion on the central surface portion of the surface layer 38.

垂直電荷転送路２１の埋め込みチャネル（ｎ＋層）３１の下には基板１よりｐ濃度の高いｐ層４１が形成されており、このｎ層３１及びｐ層４１と、図示の例では右隣のフォトダイオード２２との間に、素子分離帯としてのｐ＋領域４２が形成される。各ｐ層４１の下には、半導体基板１より高濃度なｐ−領域４２が設けられ、隣接するフォトダイオード２２間の素子分離が図られる。各ｐ−領域４２は、上述した画素区画部分すなわち遮光部材２８に対応する箇所に設けられる。 A p layer 41 having a higher p concentration than the substrate 1 is formed under the buried channel (n + layer) 31 of the vertical charge transfer path 21, and the n layer 31 and the p layer 41 are adjacent to the right side in the illustrated example. A p + region 42 as an element isolation band is formed between the first photodiode 22 and the second photodiode 22. Under each p layer 41, a p − region 42 having a higher concentration than that of the semiconductor substrate 1 is provided, and element isolation between adjacent photodiodes 22 is achieved. Each p − region 42 is provided at a location corresponding to the pixel partition portion, that is, the light shielding member 28 described above.

垂直電荷転送路２１の埋め込みチャネル３１の下に形成されたｐ層４１は、図示の例では左隣のｎ層３５の表面端部の上まで延び、この端部分のｐ＋表面層３８は、ｎ層３５の右端面位置より後退した位置になっている。そして、転送電極膜３３の左端面は、ｐ層４１の左端面まで重なる様に延設され、ｎ層３５と、転送電極膜３３及びｐ層４１の表面端部とが若干オーバーラップする構成になっている。 The p layer 41 formed below the buried channel 31 of the vertical charge transfer path 21 extends to the top of the surface end of the n layer 35 adjacent to the left in the illustrated example, and the p + surface layer 38 at this end is The position is set back from the position of the right end surface of the n layer 35. The left end surface of the transfer electrode film 33 extends so as to overlap the left end surface of the p layer 41, and the n layer 35 and the surface end portions of the transfer electrode film 33 and the p layer 41 slightly overlap. It has become.

この様なオーバーラップ構成が可能なのは、裏面照射型では半導体基板１の表面側に面積的な余裕があるためである。被写体からの入射光が、フォトダイオードや信号読出回路が設けられた側から入射する表面照射型では、面積的余裕がないため、転送電極膜の端部はフォトダイオードの端部に一致する位置までしか延設できず、間にｐ層を介在させることができない。   Such an overlap configuration is possible because the back-illuminated type has an area margin on the front surface side of the semiconductor substrate 1. In the front-illuminated type in which incident light from the subject is incident from the side where the photodiode and signal readout circuit are provided, there is no area margin, so the end of the transfer electrode film reaches the position where it matches the end of the photodiode. However, the p layer cannot be interposed between them.

本実施形態の様に、転送電極膜３３とｎ層３５との間にｐ層４１を介在させると、転送電極膜（読出電極兼用）３３に印加する読出電圧の低電圧化を図ることができ、ＣＣＤ型固体撮像素子の低消費電力化を図ることが可能となる。   If the p layer 41 is interposed between the transfer electrode film 33 and the n layer 35 as in this embodiment, the read voltage applied to the transfer electrode film (also used as the read electrode) 33 can be reduced. Thus, it is possible to reduce the power consumption of the CCD solid-state imaging device.

半導体基板１の最表面に形成される絶縁層３２の上に例えばポリシリコン膜でなる転送電極膜３３が形成され、その上に、絶縁層４５が積層される。そして、ｎ＋層３９の上の絶縁層３２，４５に開口が開けられ、絶縁層４５の上に金属電極４６が積層されることで、ｎ＋層３９と電極４６とがコンタクトされる。電極４６は、この裏面照射型固体撮像素子１００のオーバーフロードレインとして機能する。 A transfer electrode film 33 made of, for example, a polysilicon film is formed on the insulating layer 32 formed on the outermost surface of the semiconductor substrate 1, and an insulating layer 45 is stacked thereon. Then, an opening is opened in the insulating layer 32 and 45 on the n + layer 39, the metal electrode 46 on the insulating layer 45 that are stacked, and the n + layer 39 and the electrode 46 is contact. The electrode 46 functions as an overflow drain of the backside illumination type solid-state imaging device 100.

斯かる構成の裏面照射型固体撮像素子１００で被写体画像を撮像する場合、被写界からの入射光は、半導体基板１の裏面側から入射する。この入射光はマイクロレンズ２４で集光され、カラーフィルタ層２３を通り、半導体基板１内に進入する。   When a subject image is picked up by the backside illumination type solid-state imaging device 100 having such a configuration, incident light from the object scene enters from the backside of the semiconductor substrate 1. The incident light is collected by the microlens 24, passes through the color filter layer 23, and enters the semiconductor substrate 1.

マイクロレンズ２４で集光された光が半導体基板１内に入射すると、この入射光は当該マイクロレンズ２４及びカラーフィルタ２３に対応するフォトダイオード２２の方向に集光しながら進み、半導体基板１に光吸収され、光電変換されて正孔電子対が発生する。   When the light condensed by the microlens 24 enters the semiconductor substrate 1, the incident light travels while condensing in the direction of the photodiode 22 corresponding to the microlens 24 and the color filter 23, and enters the semiconductor substrate 1. It is absorbed and photoelectrically converted to generate hole electron pairs.

裏面照射型固体撮像素子１００では、半導体基板１の裏面からフォトダイオードを構成するｎ領域２２までの距離を、９μｍ程度の厚さにしているため、入射光が半導体基板１の表面側に設けたｎ＋領域すなわち電荷転送路２１に達するまでに殆ど全て基板１に吸収され光電変換されてしまう。従って、垂直電荷転送路２１を遮光する必要がない。 In the back-illuminated solid-state imaging device 100, since the distance from the back surface of the semiconductor substrate 1 to the n region 22 constituting the photodiode is about 9 μm, incident light is provided on the front surface side of the semiconductor substrate 1. Almost all of the light is absorbed by the substrate 1 and photoelectrically converted before reaching the n + region, that is, the charge transfer path 21. Therefore, it is not necessary to shield the vertical charge transfer path 21 from light.

各画素の光電変換領域（ｐ層２５からｎ領域３５までの領域）で発生した正孔は高濃度ｐ層２５に吸収され、アースに廃棄される。各画素の光電変換領域で発生した電子は、当該画素におけるｎ領域３５に蓄積され、読出電極兼用の転送電極膜３３に読出電圧が印加されると、ｎ領域３５から、図示する例では右隣の埋め込みチャネル３１に読み出される。以後、垂直電荷転送路２１に沿って水平電荷転送路（図示せず）まで転送され、水平電荷転送路に沿ってアンプまで転送され、アンプが信号電荷量に応じた電圧値信号を撮像画像信号として出力する。   Holes generated in the photoelectric conversion regions (regions from the p layer 25 to the n region 35) of each pixel are absorbed by the high concentration p layer 25 and discarded to the ground. Electrons generated in the photoelectric conversion region of each pixel are accumulated in the n region 35 in the pixel, and when a read voltage is applied to the transfer electrode film 33 that also serves as a read electrode, the n region 35 causes a right neighbor in the illustrated example. To the embedded channel 31. Thereafter, the signal is transferred along the vertical charge transfer path 21 to the horizontal charge transfer path (not shown), transferred along the horizontal charge transfer path to the amplifier, and the amplifier outputs a voltage value signal corresponding to the signal charge amount to the captured image signal. Output as.

この様な動作を行う裏面照射型固体撮像素子１００では、入射光は図示しない撮影レンズを通して入ってくるため、斜め入射光になっている。従って、遮光部材２８が無いと、図１に示す例では、赤色（Ｒ）フィルタを通過した入射光が、青色（Ｂ）フィルタに対応するフォトダイオード２２に入射し、混色が発生してしまう。   In the back-illuminated solid-state imaging device 100 that performs such an operation, incident light enters through a photographing lens (not shown), and thus is obliquely incident light. Accordingly, in the example shown in FIG. 1, if the light shielding member 28 is not provided, incident light that has passed through the red (R) filter enters the photodiode 22 corresponding to the blue (B) filter, and color mixing occurs.

この混色を避けるために遮光部材２８を設けるのであるが、本実施形態の遮光部材２８は、単に、反射防止膜２７の裏面側表面に積層するだけの薄い遮光膜とするのではなく、半導体基板１に埋め込まれるように、即ち、フォトダイオード２２に近づけるようにして形成される。これにより、遮光部材２８の遮光性能が向上する。   In order to avoid this color mixture, the light shielding member 28 is provided, but the light shielding member 28 of the present embodiment is not simply a thin light shielding film that is laminated on the back surface of the antireflection film 27, but a semiconductor substrate. It is formed so as to be embedded in 1, that is, close to the photodiode 22. Thereby, the light shielding performance of the light shielding member 28 is improved.

尚、図１に示す遮光部材２８は導電性部材で形成されており、この遮光部材２８に所定の電位（アース電位を含む。）を印加することで固体撮像素子の動作性能向上を図ってもよい。   The light shielding member 28 shown in FIG. 1 is formed of a conductive member. Even if a predetermined potential (including a ground potential) is applied to the light shielding member 28, the operation performance of the solid-state imaging device can be improved. Good.

図３は、図１に示す裏面照射型固体撮像素子１００の遮光部材２８の製造工程説明図である。先ず、高濃度ｐ＋＋層２５が形成され裏面側表面に酸化膜２６が形成されたｐ型半導体基板１にレジスト６１を塗布し、レジスト６１の遮光部材形成箇所のレジストを除去する。そして、裏面側をエッチングする（工程ａ）。 FIG. 3 is an explanatory diagram of the manufacturing process of the light shielding member 28 of the backside illumination type solid-state imaging device 100 shown in FIG. First, a resist 61 is applied to the p-type semiconductor substrate 1 on which the high-concentration p ++ layer 25 is formed and the oxide film 26 is formed on the back surface, and the resist at the light shielding member forming portion of the resist 61 is removed. Then, the back side is etched (step a).

このエッチングにより、半導体基板１の裏面側に、各画素を区画する凹所６２が境界線上に形成される（工程ｂ）。この凹所６２は、本実施形態では、高濃度ｐ＋＋層２５を突き抜けない深さとする。 By this etching, a recess 62 that partitions each pixel is formed on the boundary line on the back surface side of the semiconductor substrate 1 (step b). In this embodiment, the recess 62 has a depth that does not penetrate the high-concentration p ++ layer 25.

次に、凹所６２の内表面を酸化して酸化膜６３を形成する。裏面表面の酸化膜６３は、酸化膜２６と一体化される（工程ｃ）。   Next, the inner surface of the recess 62 is oxidized to form an oxide film 63. The oxide film 63 on the back surface is integrated with the oxide film 26 (step c).

次に、半導体基板１の裏面全面にタングステン膜２８ａをＰＶＤまたはＣＶＤにて形成し、凹所６２内を埋める（工程ｄ）。次に、裏面側表面を酸化膜２６をストッパとしてＣＭＰ（ケミカルメカニカルポリッシング）にて削成する（工程ｅ）。   Next, a tungsten film 28a is formed on the entire back surface of the semiconductor substrate 1 by PVD or CVD to fill the recess 62 (step d). Next, the rear surface is polished by CMP (chemical mechanical polishing) using the oxide film 26 as a stopper (step e).

次に、酸化膜２６の表面にタングステン膜２８ｂを更にＰＶＤまたはＣＶＤにて積層し、その上にレジスト６４を塗布する。そして、レジスト６４のうち凹所６２対応箇所のレジストを残し、裏面全体をエッチングする（工程ｆ）。   Next, a tungsten film 28b is further laminated on the surface of the oxide film 26 by PVD or CVD, and a resist 64 is applied thereon. Then, the resist corresponding to the recess 62 is left out of the resist 64, and the entire back surface is etched (step f).

これにより、タングステンによる遮光部材２８が、半導体基板１内に埋め込まれると共に、半導体基板１の裏面側に突出する形状となる（工程ｇ）。   As a result, the light shielding member 28 made of tungsten is embedded in the semiconductor substrate 1 and protrudes to the back side of the semiconductor substrate 1 (step g).

次に、半導体基板１の裏面側に、反射防止膜２７を積層し、その上に、カラーフィルタ２３を積層する（工程ｈ）。   Next, the antireflection film 27 is laminated on the back side of the semiconductor substrate 1, and the color filter 23 is laminated thereon (step h).

以上が、図１に示す裏面照射型固体撮像素子１００の遮光部材２８側の製造工程である。この様に製造することで、遮光部材２８を半導体基板１内に埋設状態で形成でき、更に、半導体基板１の裏面側に突出する形状で形成でき、遮光部材２８の光入射方向の長さが長くなり、それだけ遮光性能が向上する。   The above is the manufacturing process on the light shielding member 28 side of the back-illuminated solid-state imaging device 100 shown in FIG. By manufacturing in this way, the light shielding member 28 can be formed in an embedded state in the semiconductor substrate 1 and further formed in a shape protruding to the back side of the semiconductor substrate 1, and the length of the light shielding member 28 in the light incident direction can be increased. The light shielding performance is improved accordingly.

また、本実施形態では、反射防止膜２７が画素毎に遮光部材２８で区画されることになる。反射防止膜２７は、透明部材であるため、斜め入射光が反射防止膜２７内で多重反射して隣接画素内に進入してしまう虞がある。特に、画素の微細化が進むほど、これが無視できなくなる可能性がある。しかし、本実施形態では、反射防止膜２７が画素毎に分断されるため、この虞が無い。   In the present embodiment, the antireflection film 27 is partitioned by the light shielding member 28 for each pixel. Since the antireflection film 27 is a transparent member, there is a possibility that obliquely incident light may be multiple-reflected in the antireflection film 27 and enter the adjacent pixels. In particular, as the pixels become finer, this may not be ignored. However, in this embodiment, since the antireflection film 27 is divided for each pixel, there is no possibility of this.

図４は、図１の裏面照射型固体撮像素子１００における遮光部材２８の裏面側先端部を、先細に形成する場合の製造工程説明図である。この様に、遮光部材２８の裏面側先端部を先細にするには、図３の工程ｆで用いたレジスト６４の代わりに、先細となるレジスト６５を用いる（図４の工程ｆ’）ことで、先細の遮光部材２８’（図４の工程ｇ’）を得ることができる。   FIG. 4 is an explanatory diagram of a manufacturing process in a case where the back surface side tip of the light shielding member 28 in the back surface irradiation type solid-state imaging device 100 of FIG. In this way, in order to taper the tip on the back side of the light shielding member 28, a tapered resist 65 is used instead of the resist 64 used in step f of FIG. 3 (step f ′ of FIG. 4). A tapered light shielding member 28 '(step g' in FIG. 4) can be obtained.

遮光部材２８の裏面側先端部を先細形状とすることで、裏面側開口率が向上し、更なる高感度化を図ることが可能となる。   By forming the tip of the back side of the light shielding member 28 in a tapered shape, the opening rate on the back side can be improved and further enhancement of sensitivity can be achieved.

図５は、別実施形態に係る遮光部材２８”を示す図である。図１，図３の実施形態では、半導体基板１内に埋め込み形成した遮光部材２８を、半導体基板１の裏面側にも突出させた形状としたが、本実施形態の遮光部材２８”は、埋め込み部分のみの形状としている。この構成でも、遮光性能の向上を図ることができる。   FIG. 5 is a view showing a light shielding member 28 ″ according to another embodiment. In the embodiment of FIGS. 1 and 3, the light shielding member 28 embedded in the semiconductor substrate 1 is also provided on the back side of the semiconductor substrate 1. Although the protruding shape is used, the light shielding member 28 '' of the present embodiment has a shape of only the embedded portion. Even with this configuration, the light shielding performance can be improved.

尚、本実施形態では、反射防止膜２７は、遮光部材２８”で分断される構造にはならず、裏面側の受光面全面で連続する反射防止膜２７となっている。このため、反射防止膜２７内での多重反射による混色の可能性が生じるが、画素の微細化を図らないのであれば、この混色の可能性は低く、問題とはならない。   In the present embodiment, the antireflection film 27 does not have a structure divided by the light shielding member 28 ″, but is an antireflection film 27 continuous over the entire light receiving surface on the back surface side. Although there is a possibility of color mixing due to multiple reflection in the film 27, if the pixels are not miniaturized, the possibility of color mixing is low and this does not cause a problem.

図１に示す実施形態では、半導体基板１内に埋め込み形成した遮光部材２８が、高濃度ｐ＋＋層２５を突き抜けない構造としている。これは、遮光部材２８の外周面を酸化膜６３で覆い絶縁しているためである。 In the embodiment shown in FIG. 1, the light shielding member 28 embedded in the semiconductor substrate 1 has a structure that does not penetrate the high-concentration p ++ layer 25. This is because the outer peripheral surface of the light shielding member 28 is covered and insulated by the oxide film 63.

即ち、外周面が電気的に絶縁された遮光部材２８をｐ＋＋層２５を突き抜けて形成すると、図２から分かるように、ｐ＋＋層２５が遮光部材２８によって分断され、同一電圧（図１に示す例ではアース電位）をｐ＋＋層２５の全体に印加することができなくなってしまう。つまり、光電変換により生じた正孔を外部に廃棄することができなくなってしまう。 That is, the light shielding member 28 which outer circumferential surface is electrically insulated to form penetrates the p ++ layer 25, as can be seen from FIG. 2, p ++ layer 25 is divided by the light shielding member 28, the same voltage (Fig. 1 In the example shown, the ground potential) cannot be applied to the entire p ++ layer 25. That is, holes generated by photoelectric conversion cannot be discarded outside.

しかし、図６に示す様に、ｐ＋＋層２５の厚さｄ１より遮光部材６８の埋め込み深さ（酸化膜６３を含む）ｄ２を深くし、遮光部材６８の光入射方向の長さを長くして遮光性能向上を図る必要が生じる場合がある。 However, as shown in FIG. 6, the embedding depth (including the oxide film 63) d <b> 2 of the light shielding member 68 is deeper than the thickness d <b> 1 of the p ++ layer 25, and the light incident direction of the light shielding member 68 is increased. Therefore, it may be necessary to improve the light shielding performance.

この様な場合には、遮光部材６８の上面視の構造を、図２に示す様な画素毎に画素周囲全部を分断する構造ではなく、図７に示す様に、隣接する画素間で一部６６で遮光部材６８が遮断される構造にする。この一部６６では、遮光部材が存在しないため、この部分６６から光が若干漏れる虞がある。   In such a case, the structure of the light shielding member 68 in a top view is not a structure in which the entire periphery of the pixel is divided for each pixel as shown in FIG. 2, but a part between adjacent pixels as shown in FIG. 66, the light shielding member 68 is blocked. In this part 66, since there is no light shielding member, there is a possibility that light leaks slightly from this part 66.

裏面照射型固体撮像素子１００の受光面を、図８に示す様に、チップ上端側，チップ右端側，チップ左端側，チップ下端側に分けて考えた場合、図示しない撮影レンズを通して入射してくる光は、撮影レンズの中心光軸に対して広がる様に受光面に入ってくる。   As shown in FIG. 8, when the light receiving surface of the back-illuminated solid-state imaging device 100 is divided into the upper end side of the chip, the right end side of the chip, the left end side of the chip, and the lower end side of the chip, it enters through a photographing lens (not shown). The light enters the light receiving surface so as to spread with respect to the central optical axis of the photographing lens.

そこで、遮光部材６８の全体形状を、図９に示す様に、光の入射方向に上記遮光部材の分断部（画素間の連続部）６６が生じない様にして隣接画素間でｐ＋＋層２５が連続するようにする。これにより、光の漏れが極めて小さくなると共に、ｐ＋＋層２５全体への所定電圧印加が可能となる。 Therefore, as shown in FIG. 9, the entire shape of the light shielding member 68 is such that the light shielding member dividing portion (continuous portion between pixels) 66 does not occur in the light incident direction, and the p ++ layer 25 between adjacent pixels. To be continuous. Thereby, the leakage of light becomes extremely small, and a predetermined voltage can be applied to the entire p ++ layer 25.

図１０は、本発明の別実施形態に係る裏面照射型固体撮像素子の遮光部材の製造工程説明図である。本実施形態では、ｐ型半導体基板１の表面に形成された酸化膜２６の上の全面に先ず反射防止膜２７を積層し（工程（１））、次に、レジスト６１を塗布すると共にレジスト６１の遮光部材形成箇所のレジストを除去し、裏面側をエッチングする（工程（２））。   FIG. 10 is an explanatory diagram of the manufacturing process of the light shielding member of the backside illumination type solid-state imaging device according to another embodiment of the present invention. In this embodiment, an antireflection film 27 is first laminated on the entire surface of the oxide film 26 formed on the surface of the p-type semiconductor substrate 1 (step (1)), and then a resist 61 is applied and the resist 61 is applied. The light-shielding member forming portion is removed, and the back side is etched (step (2)).

このエッチングにより、半導体基板１の裏面側に、各画素を区画する凹所６２が形成される（工程（３））。   By this etching, a recess 62 that partitions each pixel is formed on the back side of the semiconductor substrate 1 (step (3)).

次に、図３の実施形態と異なり、凹所６２の内表面を酸化することなく、半導体基板１の裏面全面にタングステン膜２８ａをＰＶＤまたはＣＶＤにて形成し、凹所６２内を埋める（工程（４））。   Next, unlike the embodiment of FIG. 3, a tungsten film 28a is formed on the entire back surface of the semiconductor substrate 1 by PVD or CVD without oxidizing the inner surface of the recess 62, thereby filling the recess 62 (step). (4)).

次に、裏面側表面を反射防止膜２７までＣＭＰにて削成する（工程（５））。そして、再び反射防止膜２７の表面にタングステン膜２８ｂをＰＶＤまたはＣＶＤにて積層し、その上にレジスト６４を塗布し、レジスト６４のうち凹所６２対応箇所のレジストを残し、裏面全体をエッチングする（工程（６））。   Next, the back side surface is cut down to the antireflection film 27 by CMP (step (5)). Then, a tungsten film 28b is again laminated on the surface of the antireflection film 27 by PVD or CVD, and a resist 64 is applied thereon, leaving a resist corresponding to the recess 62 in the resist 64, and etching the entire back surface. (Step (6)).

これにより、タングステンによる遮光部材２８が、半導体基板１内に埋め込まれると共に、半導体基板１の裏面側に突出する形状となる（工程（７））。そして、半導体基板１の裏面側に、カラーフィルタ２３を積層する（工程（８））。   As a result, the light shielding member 28 made of tungsten is embedded in the semiconductor substrate 1 and protrudes to the back side of the semiconductor substrate 1 (step (7)). And the color filter 23 is laminated | stacked on the back surface side of the semiconductor substrate 1 (process (8)).

この実施形態では、タングステンの半導体基板埋設部表面を酸化しないため、メタル金属が半導体基板１に直接接触することになる。従って、半導体基板１がメタル金属で汚染されない様にする処理が必要となる。しかし、図１０ではｐ＋＋層２５は図示していないが、導電性遮光部材２８に所定の負電圧を印加することでｐ＋＋層２５で吸収する正孔を遮光部材２８を通して廃棄することが可能となる。 In this embodiment, since the surface of the buried semiconductor substrate of tungsten is not oxidized, the metal metal comes into direct contact with the semiconductor substrate 1. Therefore, a process for preventing the semiconductor substrate 1 from being contaminated with metal metal is required. However, although the p ++ layer 25 is not illustrated in FIG. 10, holes absorbed by the p ++ layer 25 can be discarded through the light shielding member 28 by applying a predetermined negative voltage to the conductive light shielding member 28. It becomes.

遮光部材２８の材料としてメタル金属でない材料を用いることも可能である。この様な場合に図１０の実施形態は最適である。また、図１０の実施形態でも、図４で説明して様に、遮光部材２８の先端部を先細形状にすることができる。   It is also possible to use a material that is not a metal metal as the material of the light shielding member 28. In such a case, the embodiment of FIG. 10 is optimal. Also in the embodiment of FIG. 10, as described in FIG. 4, the tip of the light shielding member 28 can be tapered.

図１１は、図１０の実施形態の変形例を示す図である。この図１１では、図５と同様に、半導体基板１内に埋設形成した遮光部材２８の裏面側先端部を突出させない形状としている。この場合、図５の実施形態と異なり、遮光部材２８は、反射防止膜２７を分断する構成になる。   FIG. 11 is a diagram showing a modification of the embodiment of FIG. In FIG. 11, similarly to FIG. 5, the rear end portion on the back surface side of the light shielding member 28 embedded in the semiconductor substrate 1 is not projected. In this case, unlike the embodiment of FIG. 5, the light shielding member 28 is configured to divide the antireflection film 27.

本発明に係る裏面照射型固体撮像素子は、画素間を分離する遮光部材を半導体基板に埋設して設けたため、光電変換効率を犠牲にすることなく、画素間のクロストーク，混色等を好適に抑制することができ、高感度撮影を行うデジタルカメラ等に搭載する撮像素子として有用である。   The back-illuminated solid-state imaging device according to the present invention is provided with a light shielding member for separating pixels embedded in a semiconductor substrate, so that crosstalk between pixels, color mixing, and the like are suitably performed without sacrificing photoelectric conversion efficiency. It can be suppressed and is useful as an image sensor mounted on a digital camera or the like that performs high-sensitivity shooting.

本発明の一実施形態に係る裏面照射型固体撮像素子の断面模式図である。It is a cross-sectional schematic diagram of the backside illumination type solid-state image sensor which concerns on one Embodiment of this invention. 図１に示す遮光部材を裏面側から見た平面図である。It is the top view which looked at the light-shielding member shown in FIG. 1 from the back surface side. 図１に示す裏面照射型固体撮像素子の遮光部材の製造工程説明図である。It is manufacturing process explanatory drawing of the light-shielding member of the back irradiation type solid-state image sensor shown in FIG. 図３に示す実施形態の変形例の説明図である。It is explanatory drawing of the modification of embodiment shown in FIG. 図１に示す実施形態とは別実施形態に係る遮光部材の断面模式図である。It is a cross-sectional schematic diagram of the light shielding member which concerns on embodiment different from embodiment shown in FIG. 図１に示す裏面照射型固体撮像素子において遮光部材がｐ＋＋層２５を突き抜けて形成される場合の断面模式図である。FIG. 2 is a schematic cross-sectional view in the case where a light shielding member is formed through a p ++ layer 25 in the backside illumination type solid-state imaging device shown in FIG. 図６で説明した遮光部材を裏面側から見た平面図である。It is the top view which looked at the light-shielding member demonstrated in FIG. 6 from the back surface side. 裏面照射型固体撮像素子の受光面の説明図である。It is explanatory drawing of the light-receiving surface of a back irradiation type solid-state image sensor. 図８に示すチップの上下左右における図７の遮光部材の配置図である。FIG. 9 is a layout view of the light shielding members of FIG. 7 on the top, bottom, left and right of the chip shown in FIG. 8. 本発明の別実施形態に係る遮光部材の製造工程説明図である。It is manufacturing process explanatory drawing of the light-shielding member which concerns on another embodiment of this invention. 図１０に示す実施形態とは別実施形態に係る遮光部材の断面模式図である。It is a cross-sectional schematic diagram of the light-shielding member which concerns on embodiment different from embodiment shown in FIG.

符号の説明Explanation of symbols

１ ｐ型半導体基板
２２ フォトダイオード（ｎ領域）
２３ カラーフィルタ
２４ マイクロレンズ（トップレンズ）
２５ 正孔引き抜き用の高濃度ｐ＋＋層
２６ 酸化膜
２７ 反射防止膜
２８，２８’，２８”，６８ 遮光部材
６６ 遮光部材の分断部分 1 p-type semiconductor substrate 22 photodiode (n region)
23 Color filter 24 Micro lens (Top lens)
25 High-concentration p ++ layer 26 for extracting holes 26 Oxide film 27 Antireflection films 28, 28 ′, 28 ″, 68 Shielding member 66 Dividing portion of shielding member

Claims (19)

半導体基板と、該半導体基板の表面側に二次元アレイ状に形成され該半導体基板の裏面側から入射した光によって光電変換された信号電荷を蓄積する複数のフォトダイオードと、前記裏面側に形成され前記光電変換により前記信号電荷と対で発生する電荷を引き寄せる高濃度不純物層と、該高濃度不純物層が隣接フォトダイオード間で少なくとも一部が連続するように該高濃度不純物層に埋設され前記各フォトダイオードへの入射光を隣接する前記フォトダイオードから区画する遮光部材とを備えることを特徴とする裏面照射型固体撮像素子。 A semiconductor substrate, a plurality of photodiodes that are formed in a two-dimensional array on the front side of the semiconductor substrate and store signal charges photoelectrically converted by light incident from the back side of the semiconductor substrate, and formed on the back side A high-concentration impurity layer that attracts the charge generated in pairs with the signal charge by the photoelectric conversion; and the high-concentration impurity layer is embedded in the high-concentration impurity layer so that at least a part thereof is continuous between adjacent photodiodes. A back-illuminated solid-state imaging device, comprising: a light shielding member that partitions incident light on the photodiode from the adjacent photodiode. 前記遮光部材は導電性材料で形成され、該遮光部材は前記高濃度不純物層内に絶縁膜を被覆した状態で埋設されることを特徴とする請求項１に記載の裏面照射型固体撮像素子。   The back-illuminated solid-state imaging device according to claim 1, wherein the light shielding member is formed of a conductive material, and the light shielding member is embedded in the high concentration impurity layer in a state of covering an insulating film. 前記遮光部材は導電性材料で形成され、前記高濃度不純物層に直接接触する前記遮光部材は該高濃度不純物層を突き抜けて形成されることを特徴とする請求項１に記載の裏面照射型固体撮像素子。   2. The back-illuminated solid according to claim 1, wherein the light shielding member is formed of a conductive material, and the light shielding member in direct contact with the high concentration impurity layer penetrates the high concentration impurity layer. Image sensor. 前記遮光部材の埋め込み深さが前記高濃度不純物層を突き抜けて形成され、該遮光部材には、光の入射方向に該遮光部材の分断部が生じないようにして隣接画素間で前記高濃度不純物層を連続させる一部欠損部が設けられる請求項２に記載の裏面照射型固体撮像素子。   The light shielding member has a buried depth penetrating the high-concentration impurity layer, and the light-shielding member has the high-concentration impurity between adjacent pixels so that the light-shielding member is not divided in the light incident direction. The back-illuminated solid-state imaging device according to claim 2, wherein a partial defect portion that makes the layers continuous is provided. 前記遮光部材は、前記裏面側から突出して形成されることを特徴とする請求項１乃至請求項４のいずれかに記載の裏面照射型固体撮像素子。   5. The backside illumination type solid-state imaging device according to claim 1, wherein the light shielding member is formed to protrude from the backside. 前記裏面側の表面には絶縁膜と反射防止膜とが形成されることを特徴とする請求項１乃至請求項５のいずれかに記載の裏面照射型固体撮像素子。   The backside illumination type solid-state imaging device according to claim 1, wherein an insulating film and an antireflection film are formed on the surface on the backside. 前記反射防止膜は前記遮光部材によって分断されることを特徴とする請求項６に記載の裏面照射型固体撮像素子。   The back-illuminated solid-state imaging device according to claim 6, wherein the antireflection film is divided by the light shielding member. 前記遮光部材の前記裏面側先端部が先細に形成されることを特徴とする請求項１乃至請求項７のいずれかに記載の裏面照射型固体撮像素子。   The backside irradiation type solid-state imaging device according to any one of claims 1 to 7, wherein a tip of the backside of the light shielding member is tapered. 前記遮光部材には所定電圧が印加されることを特徴とする請求項３に記載の裏面照射型固体撮像素子。   The back-illuminated solid-state imaging device according to claim 3, wherein a predetermined voltage is applied to the light shielding member. 前記所定電圧は、前記半導体基板の周辺部に設けられた回路から印加されることを特徴とする請求項９に記載の裏面照射型固体撮像素子。   The back-illuminated solid-state imaging device according to claim 9, wherein the predetermined voltage is applied from a circuit provided in a peripheral portion of the semiconductor substrate. 表面側に複数のフォトダイオードが二次元アレイ状に形成され、裏面側から入射した光によって光電変換された信号電荷が前記フォトダイオードに蓄積される半導体基板の前記裏面側に、前記光電変換により前記信号電荷と対で発生する電荷を引き寄せる高濃度不純物層を形成し、該裏面のうち、前記各フォトダイオードへの入射光を隣接する前記フォトダイオードから区画する境界位置をエッチングにより削り、該境界位置の前記高濃度不純物層に、該高濃度不純物層が隣接フォトダイオード間で少なくとも一部が連続するように遮光材料を埋設することを特徴とする裏面照射型固体撮像素子の製造方法。 A plurality of photodiodes are formed in a two-dimensional array on the front side, and signal charges photoelectrically converted by light incident from the back side are accumulated on the back side of the semiconductor substrate in the photodiodes by the photoelectric conversion. Forming a high-concentration impurity layer that attracts the charge generated in pairs with the signal charge, and etching the boundary position of the back surface that partitions incident light to each photodiode from the adjacent photodiode; A method of manufacturing a backside illumination type solid-state imaging device, wherein a light shielding material is embedded in the high concentration impurity layer so that at least a part of the high concentration impurity layer is continuous between adjacent photodiodes . 前記遮光部材は導電性材料で形成され、該遮光部材は前記高濃度不純物層内に絶縁膜を被覆した状態で埋設されることを特徴とする請求項１１に記載の裏面照射型固体撮像素子の製造方法。   The backside illumination type solid-state imaging device according to claim 11, wherein the light shielding member is formed of a conductive material, and the light shielding member is embedded in the high concentration impurity layer in a state of covering an insulating film. Production method. 前記遮光部材は導電性材料で形成され、前記高濃度不純物層に直接接触する前記遮光部材は該高濃度不純物層を突き抜けて形成されることを特徴とする請求項１１に記載の裏面照射型固体撮像素子の製造方法。   The back-illuminated solid according to claim 11, wherein the light shielding member is formed of a conductive material, and the light shielding member in direct contact with the high-concentration impurity layer penetrates the high-concentration impurity layer. Manufacturing method of imaging device. 前記遮光部材の埋め込み深さが前記高濃度不純物層を突き抜けて形成され、該遮光部材には、光の入射方向に該遮光部材の分断部が生じないようにして隣接画素間で前記高濃度不純物層を連続させる一部欠損部が設けられることを特徴とする請求項１２に記載の裏面照射型固体撮像素子の製造方法。   The light shielding member has a buried depth penetrating the high-concentration impurity layer, and the light-shielding member has the high-concentration impurity between adjacent pixels so that the light-shielding member is not divided in the light incident direction. The method for manufacturing a backside illumination type solid-state imaging device according to claim 12, wherein a partial defect portion for continuing the layers is provided. 前記遮光部材は、前記裏面側から突出して形成されることを特徴とする請求項１１乃至請求項１４のいずれかに記載の裏面照射型固体撮像素子の製造方法。   The method of manufacturing a backside illumination type solid-state imaging device according to any one of claims 11 to 14, wherein the light shielding member is formed to protrude from the backside. 前記裏面側の表面には絶縁膜と反射防止膜とが形成されることを特徴とする請求項１１乃至請求項１５のいずれかに記載の裏面照射型固体撮像素子の製造方法。   The method for manufacturing a backside illumination type solid-state imaging device according to any one of claims 11 to 15, wherein an insulating film and an antireflection film are formed on the surface on the backside. 前記反射防止膜は前記遮光部材によって分断されることを特徴とする請求項１６に記載の裏面照射型固体撮像素子の製造方法。   The method of manufacturing a backside illumination type solid-state imaging device according to claim 16, wherein the antireflection film is divided by the light shielding member. 前記遮光部材の前記裏面側先端部が先細に形成されることを特徴とする請求項１１乃至請求項１７のいずれかに記載の裏面照射型固体撮像素子の製造方法。   The method for manufacturing a backside illumination solid-state imaging device according to any one of claims 11 to 17, wherein the backside tip of the light shielding member is tapered. 前記遮光部材に所定電圧を印加する周辺回路が前記半導体基板に形成されることを特徴とする請求項１３に記載の裏面照射型固体撮像素子の製造方法。   The method of manufacturing a backside illumination type solid-state imaging device according to claim 13, wherein a peripheral circuit that applies a predetermined voltage to the light shielding member is formed on the semiconductor substrate.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103545325A (en) * 2012-07-13 2014-01-29 株式会社东芝 Solid state imaging device

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2906079B1 (en) * 2006-09-19 2009-02-20 E2V Semiconductors Soc Par Act COLOR IMAGE SENSOR WITH ENHANCED COLORIMETRY
JP5478217B2 (en) 2009-11-25 2014-04-23 パナソニック株式会社 Solid-state imaging device
JP5663925B2 (en) * 2010-03-31 2015-02-04 ソニー株式会社 Solid-state imaging device, manufacturing method thereof, and electronic apparatus
JP5763474B2 (en) * 2010-08-27 2015-08-12 株式会社半導体エネルギー研究所 Optical sensor
JP2012064703A (en) 2010-09-15 2012-03-29 Sony Corp Image sensor and image pick-up device
JP5579931B2 (en) * 2011-06-02 2014-08-27 富士フイルム株式会社 Solid-state imaging device
JP6168331B2 (en) * 2012-05-23 2017-07-26 ソニー株式会社 Imaging device and imaging apparatus
JP5519827B2 (en) * 2013-05-13 2014-06-11 ソニー株式会社 Solid-state imaging device and electronic device
JP6060851B2 (en) * 2013-08-09 2017-01-18 ソニー株式会社 Method for manufacturing solid-state imaging device
JP6339032B2 (en) 2015-02-19 2018-06-06 東京エレクトロン株式会社 Manufacturing method of optical device including light shielding body, and storage medium
JP6176313B2 (en) * 2015-12-02 2017-08-09 ソニー株式会社 Solid-state imaging device, manufacturing method thereof, and electronic apparatus
US9985072B1 (en) * 2016-11-29 2018-05-29 Taiwan Semiconductor Manufacturing Co., Ltd. CMOS image sensor with dual damascene grid design having absorption enhancement structure
DE102017117948B4 (en) 2016-11-29 2022-07-21 Taiwan Semiconductor Manufacturing Co. Ltd. DUAL DAMASCENE LATTICE DESIGN CMOS IMAGE SENSOR WITH AN ABSORPTION ENHANCEMENT STRUCTURE
JP6663887B2 (en) * 2017-07-11 2020-03-13 ソニー株式会社 Solid-state imaging device, manufacturing method thereof, and electronic device

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10163462A (en) * 1996-11-29 1998-06-19 Sony Corp Solid-state image sensing device of mass type filter structure and its manufacture
JP3759435B2 (en) * 2001-07-11 2006-03-22 ソニー株式会社 XY address type solid-state imaging device
JP4123415B2 (en) * 2002-05-20 2008-07-23 ソニー株式会社 Solid-state imaging device
JP4483442B2 (en) * 2004-07-13 2010-06-16 ソニー株式会社 Solid-state imaging device, solid-state imaging device, and method for manufacturing solid-state imaging device
JP4725095B2 (en) * 2004-12-15 2011-07-13 ソニー株式会社 Back-illuminated solid-state imaging device and manufacturing method thereof
JP5124934B2 (en) * 2005-02-04 2013-01-23 ソニー株式会社 Solid-state imaging device, manufacturing method thereof, and imaging apparatus
JP2006261638A (en) * 2005-02-21 2006-09-28 Sony Corp Solid state imaging device, and driving method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103545325A (en) * 2012-07-13 2014-01-29 株式会社东芝 Solid state imaging device

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