JPS6161455A - Solid-state image pickup device - Google Patents
Solid-state image pickup deviceInfo
- Publication number
- JPS6161455A JPS6161455A JP59182661A JP18266184A JPS6161455A JP S6161455 A JPS6161455 A JP S6161455A JP 59182661 A JP59182661 A JP 59182661A JP 18266184 A JP18266184 A JP 18266184A JP S6161455 A JPS6161455 A JP S6161455A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- solid
- signal line
- vertical signal
- state image
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000012535 impurity Substances 0.000 claims abstract description 10
- 238000009792 diffusion process Methods 0.000 claims description 11
- 238000003384 imaging method Methods 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 3
- 239000004065 semiconductor Substances 0.000 claims 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052698 phosphorus Inorganic materials 0.000 abstract description 2
- 239000011574 phosphorus Substances 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 29
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011229 interlayer Substances 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- -1 for example Substances 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
- H01L27/146—Imager structures
- H01L27/14643—Photodiode arrays; MOS imagers
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Electromagnetism (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Solid State Image Pick-Up Elements (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はウェル層を含む４層構造を有しランダム雑音の
発生を防止した固体撮像素子に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a solid-state imaging device that has a four-layer structure including a well layer and prevents random noise from occurring.
従来、固体撮像素子においては、主として固定パターン
雑音やプルーミングが問題とされたが、補償回路や例え
ばｎ −ｐ −ｎ ３層構造の採用によって著しく軽減
され、現在ではこれに代ってランダム雑音が問題となっ
ている。このランダム雑音は画面上のちらつきとして観
察されるもので、その発生原因の一つとして素子内部か
ら発生する成分がある。In the past, fixed pattern noise and pluming were the main problems associated with solid-state imaging devices, but these have been significantly reduced through the use of compensation circuits and, for example, the n-p-n three-layer structure, and now random noise has been replaced. This has become a problem. This random noise is observed as flickering on the screen, and one of the causes of its occurrence is a component generated from inside the element.
第１図は従来から用いられているこの種の固体撮像素子
の要部断面を示したものである０同図において、ｎ形基
板１の一主表面にｐ−形ウエル層２を設け、このｐ−形
ウエル層２に、ＭＯＳトランジスタのソースおよびドレ
インとしてのｎ 拡散層３，４、蓄積電荷量を増大させ
るｐ十層、垂直スメアな抑圧するｐ＋層６、ゲート酸化
膜７、ゲート電極８が形成されている。そして、ｎ＋拡
散層３はｐ−形ウエル層２とともにフォトダイオードを
構成するとともに、このフォトダイオードとＭＯＳ ト
ランジスタとによって光電変換素子群が構成されている
。これらの各光電変換素子は素子間分離用酸化膜９およ
び層間絶縁膜１０によつて互いに分離されておシ、ｎ＋
拡散層４はＡｌからなる垂直信号線１１に接続されてい
る（特開昭５４−１４５０７８号公報参照）。FIG. 1 shows a cross section of a main part of this type of solid-state image sensing device that has been used conventionally. In the same figure, a p-type well layer 2 is provided on one main surface of an n-type substrate 1. The p-type well layer 2 includes n diffusion layers 3 and 4 as the source and drain of the MOS transistor, a p layer to increase the amount of accumulated charge, a p+ layer 6 to suppress vertical smear, a gate oxide film 7, and a gate electrode 8. is formed. The n+ diffusion layer 3 and the p- well layer 2 constitute a photodiode, and the photodiode and the MOS transistor constitute a photoelectric conversion element group. These photoelectric conversion elements are separated from each other by an oxide film 9 for element isolation and an interlayer insulating film 10.
The diffusion layer 4 is connected to a vertical signal line 11 made of Al (see Japanese Patent Laid-Open No. 145078/1983).
このように構成される固体撮像素子において、ランダム
雑音の電流成分１ｎは、垂直信号線１１の容量をＣｖと
して１ｎ２ｏＣＣｖで表わされる成分がおる。ここでＣ
ｖは垂直信号線１１とｐ″′形ウェル層２との間の眉間
絶縁膜１０による容量成分と、ｐ＋層６およびｎ＋拡散
層４０間のｎ ＋ −ｐ＋接合の容量成分とからなる。In the solid-state imaging device configured in this manner, the random noise current component 1n includes a component expressed as 1n2oCCv, where Cv is the capacitance of the vertical signal line 11. Here C
v consists of a capacitance component due to the glabella insulating film 10 between the vertical signal line 11 and the p'' type well layer 2, and a capacitance component of the n+-p+ junction between the p+ layer 6 and the n+ diffusion layer 40.
その値はｐ中層６を形成する不純物濃度が増加するなど
垂直スメア抑圧効果は増加するが、この反面垂直信号線
１１の容（ｉｉＣｖが増加することになる０この結果、
ランダム雑音が増加し、ＳＺＮ比を低下させるという欠
点があった。The vertical smear suppression effect increases as the impurity concentration forming the p-intermediate layer 6 increases, but on the other hand, the capacitance (iiCv) of the vertical signal line 11 increases.
This has the drawback of increasing random noise and lowering the SZN ratio.
したがって本発明は前述した欠点に鑑みてなされたもの
であυ、その目的とするところは、ランダム雑音の少な
い固体撮像素子を提供することにある。Therefore, the present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a solid-state image pickup device with less random noise.
このような目的を達成するために本発明による固体撮像
素子は、垂直信号線と接触する拡散層下の部位を、ｎ”
−Ｐ−Ｐ” Ｐ−ウェル積層からなる４層構造で構成
したものである。In order to achieve such an object, the solid-state image sensor according to the present invention has a region under the diffusion layer that contacts the vertical signal line with an n''
-P-P" It has a four-layer structure consisting of P-well stacks.
次に図面を用いて本発明の実施例を詳細に説明する。２
第２図は本発明による固体撮像素子の一例を示す要部断
面構成図であシ、第１図と同一部分は同一符号を付す。Next, embodiments of the present invention will be described in detail using the drawings. 2. FIG. 2 is a cross-sectional configuration diagram of essential parts showing an example of a solid-state image sensing device according to the present invention, and the same parts as in FIG. 1 are given the same reference numerals.
同図において、ｎ＋拡散層４とｐ＋層６との間にｐ一層
１２を設けたものである。このｐ一層１２はｐ＋層６中
に、これと反対の不純物、例えば燐を拡散させれば、ｐ
形不純物層内にｎ形不純物が入シ込むことになシ、等測
的にｐ＋層６の濃度が低減されたことになる。したがっ
て、ｐ＋層６の不純物濃度をＮｐ＋とすれば、ＣｖＯｃ
ｎも１であるから、ｐ＋層６の濃度を小さくした分、容
量Ｃｖは減少することになる。In the figure, a p layer 12 is provided between an n+ diffusion layer 4 and a p+ layer 6. This p layer 12 can be formed by diffusing an opposite impurity, for example, phosphorus, into the p+ layer 6.
Since the n-type impurity does not enter the type impurity layer, the concentration of the p+ layer 6 is reduced isometrically. Therefore, if the impurity concentration of the p+ layer 6 is Np+, CvOc
Since n is also 1, the capacitance Cv decreases as the concentration of the p+ layer 6 is reduced.
以上説明したように本発明によれば、垂直信号線の容量
を低減できるので、ランダム雑音を低減でき、８／Ｎ比
の高い極めて高品位の画像を得ることができるという極
めて優れた効果を奏する。As explained above, according to the present invention, since the capacity of the vertical signal line can be reduced, random noise can be reduced, and an extremely high-quality image with a high 8/N ratio can be obtained, which is an extremely excellent effect. .
第１図は従来の固体撮像素子の一例を示す要部断面図、
第２図は本発明による固体撮像素子の一例を示す要部断
面構成図である。
１・・魯・ｎ形基板、２・Ｑ＠・ｐ″形ウェル層、３，
４・・・・ｎ＋拡散層、５，６・畳・・ｐ＋層、７・・
・・ゲート酸化膜、８・惨・・ゲート電極、９・・拳・
素子間分離用酸化膜、１０争・・Φ層間范縁膜、１１・
・−・垂直信号線、１２・・＠Φｐ一層。FIG. 1 is a cross-sectional view of essential parts showing an example of a conventional solid-state image sensor.
FIG. 2 is a cross-sectional configuration diagram of essential parts showing an example of a solid-state image sensor according to the present invention. 1. N-type substrate, 2. Q@-p″ well layer, 3.
4...n+ diffusion layer, 5, 6, tatami...p+ layer, 7...
・・Gate oxide film, 8・・Gate electrode, 9・・Fist・
Oxide film for isolation between elements, 10 types... Φ interlayer frame film, 11...
...Vertical signal line, 12...@Φp single layer.
Claims (1)
形を有するウェル層を設け、このウェル層上にフォトダ
イオードとＭＯＳトランジスタのソースとを構成する第
１導電形の第１拡散層およびドレインを構成する第１導
電形の第２拡散層ならびにゲート電極を設け、前記第２
拡散層を垂直信号線に接続した固体撮像素子において、
前記垂直信号線に接触する第２拡散層下の領域の不純物
濃度をｎ＾＋−ｐ＾−−ｐ＾＋−ｐ＾−ウェル構造とし
たことを特徴とする固体撮像素子。A well layer having a second conductivity type is provided on one main surface of a semiconductor substrate having a first conductivity type, and a first diffusion layer of the first conductivity type constituting the photodiode and the source of the MOS transistor is provided on the well layer; A second diffusion layer of the first conductivity type constituting the drain and a gate electrode are provided;
In a solid-state image sensor in which a diffusion layer is connected to a vertical signal line,
A solid-state imaging device characterized in that the impurity concentration of a region under the second diffusion layer in contact with the vertical signal line is n^+-p^--p^+-p^- well structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59182661A JPS6161455A (en) | 1984-09-03 | 1984-09-03 | Solid-state image pickup device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59182661A JPS6161455A (en) | 1984-09-03 | 1984-09-03 | Solid-state image pickup device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6161455A true JPS6161455A (en) | 1986-03-29 |
Family
ID=16122218
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59182661A Pending JPS6161455A (en) | 1984-09-03 | 1984-09-03 | Solid-state image pickup device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6161455A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04260553A (en) * | 1990-12-18 | 1992-09-16 | Howard W Demoore | Vacuum transfer device for rotary sheet-fedpress |
-
1984
- 1984-09-03 JP JP59182661A patent/JPS6161455A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04260553A (en) * | 1990-12-18 | 1992-09-16 | Howard W Demoore | Vacuum transfer device for rotary sheet-fedpress |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4791211B2 (en) | Improving quantum efficiency in active pixel sensors | |
| JPH0523505B2 (en) | ||
| JPH04355964A (en) | Solid-state image pickup device and manufacture thereof | |
| JPS6157181A (en) | Solid-state image pickup device | |
| JP2866328B2 (en) | Solid-state imaging device | |
| JP2832136B2 (en) | Solid-state imaging device and manufacturing method thereof | |
| JPH0416948B2 (en) | ||
| JPS59178769A (en) | Solid-state image pickup device | |
| JP2964571B2 (en) | Solid-state imaging device | |
| JPS6161455A (en) | Solid-state image pickup device | |
| JPS6160592B2 (en) | ||
| JP2848435B2 (en) | Solid-state imaging device | |
| JPS5842370A (en) | Solid-state image pickup device | |
| JPS589363A (en) | Solid state image pickup element | |
| JPS59163860A (en) | Solid-state image pickup element | |
| JPS6258549B2 (en) | ||
| JPS60173978A (en) | Solid-state image pickup device | |
| JPS63193559A (en) | Mos image sensor | |
| JPH0424872B2 (en) | ||
| JPS62216262A (en) | Solid-state image pickup device | |
| JPS62291961A (en) | Solid-state image pickup device | |
| JPS6255961A (en) | Solid state image pick-up device | |
| JPS58142682A (en) | Solid-state image pickup element | |
| JPH07249753A (en) | Solid state image pickup device | |
| JPS6074566A (en) | Solid-state image pickup element |