JP2738679B2 - Solid-state imaging device - Google Patents
Solid-state imaging deviceInfo
- Publication number
- JP2738679B2 JP2738679B2 JP62040327A JP4032787A JP2738679B2 JP 2738679 B2 JP2738679 B2 JP 2738679B2 JP 62040327 A JP62040327 A JP 62040327A JP 4032787 A JP4032787 A JP 4032787A JP 2738679 B2 JP2738679 B2 JP 2738679B2
- Authority
- JP
- Japan
- Prior art keywords
- film
- region
- imaging device
- solid
- state imaging
- 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.)
- Expired - Fee Related
Links
- 238000003384 imaging method Methods 0.000 title claims description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 14
- 229910052782 aluminium Inorganic materials 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 230000003287 optical effect Effects 0.000 claims description 6
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims description 5
- 229920005591 polysilicon Polymers 0.000 claims description 5
- 239000000758 substrate Substances 0.000 claims description 4
- 239000004065 semiconductor Substances 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims 1
- 239000010410 layer Substances 0.000 description 17
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
Landscapes
- Solid State Image Pick-Up Elements (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、テレビカメラ等に使用される固体撮像装置
に関する。
〔従来の技術〕
半導体基板に多数の光電変換素子を配列した固体撮像
装置において、従来より、全く光を受けない状態の基準
信号レベルを得るため、一部の光電変換素子を遮光膜で
覆うこと（オプチカル・ブラツク部）が行なわれてい
る。
第２図に、この部分の構成を示す。１はｎ形シリコン
基板、２はｐ形ウエル、3,4,5はn+領域、６はLOCOS酸化
膜からなる分離絶縁膜である。７は垂直ゲートを構成す
るポリシリコン層、８は水平ゲートを構成するポリシリ
コン層、９は5000Åの厚さの第１層アルミニウム層、10
は水平信号線を構成する第２層アルミニウム層、11はPS
G−SOG−PSGの３層構造からなる層間絶縁膜、12,13はPS
G層であり、14が遮光膜を構成する第３層アルミニウム
層である（テレビジョン学会技術報告「水平移送方式固
体撮像素子」昭和60年９月）。
〔発明が解決しようとする問題点〕
上記従来例では、ポリシリコンゲートやアルミニウム
配線層等の形成により基板に段差が生じるため、遮光膜
としてのアルミニウム層14を形成したときに、段差部で
のステツプカバレツジが悪く、図示のＡ部やＢ部におい
て、アルミニウム層14が極端に薄くなつたり破れたりし
て光の透過が起る。そのため、充分な黒化濃度が得られ
ず、オプテイカルブラツクレベルが低いという問題があ
つた。
この発明は、遮光膜の適正化によりオプテイカルブラ
ツクレベルを改善した固体撮像装置を提供することを目
的とする。
〔問題点を解決するための手段〕
上記問題点は、遮光膜を平坦化した下地の上に形成す
ることにより解決される。
〔作 用〕
予め下地を平坦にすることにより、ステツプカバレツ
ジが向上し、遮光膜がほぼ均一な膜厚で適正に形成され
る。
〔実施例〕
第１図は本発明の一実施例を示す断面図である。14A
は遮光膜としての第３層アルミニウム層であるが、第２
図に示した第３層アルミニウム層14と異なり、ほぼ均一
な膜厚（9500Å）で一様に形成されている。
このようにアルミニウム層14Aが適正に形成されたの
は、予め下地をSOG膜15により平坦にしたためである。
周知の通り、SOG膜は、SiO2を有機物に溶解したSOG液を
スピンコートし、その後熱処理することにより有機物を
揮発させ、SiO2膜を残したものであり、スピンコートの
段階で、SOG液の流動性により表面を平坦化することが
できる。
このようにSOG膜15の利用により下地を平坦化した上
にアルミニウム層14Aを形成したことにより、従来の凹
凸を有するPSG膜13の表面に直接アルミニウム層14を形
成した場合に比較して、オプテイカルブラツクレベルは
15％程度向上した。
下地を平坦化する手段は、上述した方法に限定される
ものではない。例えば、上記SOG膜15のような、下地の
凹部を埋め表面を平坦にするような膜を比較的厚く形成
した上で、その表面からプラズマエツチング等によりこ
れを除去して行くことにより、非常に高い平坦度をもつ
た表面が形成できる。
〔発明の効果〕
本発明によれば、光電変換素子が形成された領域と、
ポリシリコンゲートとアルミニウム配線とが積層された
領域との間の段差部に生じる凹部を埋めるようにSOG膜
を形成することで、遮光膜を適正に形成でき、オプテイ
カルブラツクレベルを向上させることができる。そのた
め、素子動作時のクランプを正確に行なえ、暗電流の補
正が適確に行なえる。Description: TECHNICAL FIELD The present invention relates to a solid-state imaging device used for a television camera or the like. [Prior art] In a solid-state imaging device in which a large number of photoelectric conversion elements are arranged on a semiconductor substrate, in order to obtain a reference signal level in a state in which no light is received, some photoelectric conversion elements are covered with a light-shielding film. (Optical black section) is being performed. FIG. 2 shows the configuration of this part. 1 is an n-type silicon substrate, 2 is a p-type well, 3, 4, and 5 are n + regions, and 6 is an isolation insulating film made of a LOCOS oxide film. 7 is a polysilicon layer constituting a vertical gate, 8 is a polysilicon layer constituting a horizontal gate, 9 is a first aluminum layer having a thickness of 5000 °, 10
Is the second aluminum layer constituting the horizontal signal line, and 11 is PS
G-SOG-PSG interlayer insulating film consisting of three layers, 12 and 13 are PS
The G layer is denoted by reference numeral 14, and the reference numeral 14 denotes a third aluminum layer constituting a light-shielding film (Technical Report of the Institute of Television Engineers of Japan, "Horizontal transfer type solid-state imaging device", September 1985). [Problems to be Solved by the Invention] In the above conventional example, since a step is formed on the substrate by forming a polysilicon gate, an aluminum wiring layer, and the like, when the aluminum layer 14 as a light shielding film is formed, The step coverage is poor, and in the portions A and B shown in the figure, the aluminum layer 14 becomes extremely thin or breaks, causing light transmission. For this reason, there has been a problem that a sufficient blackening density cannot be obtained and the optical black level is low. An object of the present invention is to provide a solid-state imaging device in which an optical black level is improved by optimizing a light shielding film. [Means for Solving the Problems] The above problems can be solved by forming a light shielding film on a flattened base. [Operation] By flattening the base in advance, the step coverage is improved, and the light-shielding film is appropriately formed with a substantially uniform film thickness. FIG. 1 is a sectional view showing an embodiment of the present invention. 14A
Denotes a third aluminum layer as a light shielding film,
Unlike the third aluminum layer 14 shown in the figure, it is formed uniformly with a substantially uniform film thickness (9500 °). The reason why the aluminum layer 14A was properly formed in this way is that the underlayer was previously flattened by the SOG film 15.
As is well known, the SOG film is formed by spin-coating an SOG solution in which SiO 2 is dissolved in an organic substance, and then heat-treating to volatilize the organic substance, leaving the SiO 2 film. Surface can be flattened by the fluidity of the liquid. By forming the aluminum layer 14A on the underlayer by using the SOG film 15 as described above, the optical layer is more optimistic than the conventional case where the aluminum layer 14 is formed directly on the surface of the PSG film 13 having irregularities. Icar black level
It improved about 15%. The means for flattening the underlayer is not limited to the method described above. For example, by forming a relatively thick film such as the above-mentioned SOG film 15 that fills the concave portions of the base and flattens the surface, and then removes the film from the surface by plasma etching or the like, it becomes very A surface with high flatness can be formed. [Effects of the Invention] According to the present invention, a region where a photoelectric conversion element is formed,
By forming the SOG film so as to fill the recess formed in the step between the region where the polysilicon gate and the aluminum wiring are stacked, the light-shielding film can be formed properly, and the optical black level can be improved. it can. Therefore, clamping can be performed accurately during element operation, and dark current can be corrected accurately.
【図面の簡単な説明】
第１図は本発明の一実施例を示す断面図、第２図は従来
例を示す断面図である。
14A……第３層アルミニウム層（遮光膜）、15……SOG
膜。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional example. 14A: 3rd aluminum layer (light shielding film), 15: SOG
film.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 中野 寿夫 茂原市早野3300番地 株式会社日立製作 所茂原工場内 (72)発明者 山田 光司 茂原市早野3681番地 日立デバイスエン ジニアリング株式会社内 (72)発明者 泉 章也 茂原市早野3300番地 株式会社日立製作 所茂原工場内 (56)参考文献 特開 昭61−265865（ＪＰ，Ａ) 特開 昭62−145771（ＪＰ，Ａ) 特開 昭63−25969（ＪＰ，Ａ) 特開 昭60−46674（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshio Nakano 3300 Hayano Mobara City Hitachi, Ltd. In the Tokomohara factory (72) Inventor Koji Yamada 3681 Hayano Mobara-shi Hitachi Device En Within Zineering Co., Ltd. (72) Inventor Akiya Izumi 3300 Hayano Mobara City Hitachi, Ltd. In the Tokomohara factory (56) References JP-A-61-265865 (JP, A) JP-A-62-145771 (JP, A) JP-A-63-25969 (JP, A) JP-A-60-46674 (JP, A)
Claims (1)
の一部領域の光電変換素子をオプテイカルブラツクレベ
ル検出のための遮光膜で覆った固体撮像装置において、
光電変換素子が形成された第１の領域と、該第１の領域
に隣接してポリシリコンゲートとアルミニウム配線とが
積層された第２の領域と、上記第１の領域と上記第２の
領域との間の段差部と、上記第１の領域と上記段差部と
上記第２の領域とを覆う第１の膜と、該第１の膜を覆う
第２の膜とを有し、上記第１の膜は、上記段差部で膜厚
が薄く形成され、上記第１の膜の表面には上記段差部上
において凹部が形成され、上記第２の膜は、上記段差部
で膜厚が厚く、かつ上記凹部を埋めて、上記第２の膜の
表面が平坦化するよう形成され、上記第２の膜の上に上
記遮光膜が上記第１の領域と上記第２の領域とに連続し
て形成されることを特徴とする固体撮像装置。(57) [Claims] In a solid-state imaging device in which a large number of photoelectric conversion elements are arranged on a semiconductor substrate, and a photoelectric conversion element in a partial area is covered with a light-shielding film for optical black level detection,
A first region in which a photoelectric conversion element is formed; a second region in which a polysilicon gate and an aluminum wiring are stacked adjacent to the first region; the first region and the second region A first film that covers the first region, the step, and the second region; and a second film that covers the first film. The first film is formed to have a small thickness at the step portion, the first film has a concave portion on the surface at the step portion, and the second film has a large film thickness at the step portion. The second film is formed so as to flatten the surface of the second film so as to fill the concave portion, and the light-shielding film is continuous with the first region and the second region on the second film. A solid-state imaging device characterized by being formed by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62040327A JP2738679B2 (en) | 1987-02-25 | 1987-02-25 | Solid-state imaging device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62040327A JP2738679B2 (en) | 1987-02-25 | 1987-02-25 | Solid-state imaging device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63208269A JPS63208269A (en) | 1988-08-29 |
| JP2738679B2 true JP2738679B2 (en) | 1998-04-08 |
Family
ID=12577510
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62040327A Expired - Fee Related JP2738679B2 (en) | 1987-02-25 | 1987-02-25 | Solid-state imaging device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2738679B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20010048140A1 (en) | 1997-04-10 | 2001-12-06 | Inao Toyoda | Photo sensing integrated circuit device and related circuit adjustment |
| JP3726416B2 (en) * | 1997-04-14 | 2005-12-14 | 株式会社デンソー | Optical sensor integrated circuit device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61265865A (en) * | 1985-05-20 | 1986-11-25 | Nec Corp | Solid-state image pickup element |
| JPS62145771A (en) * | 1985-12-19 | 1987-06-29 | Toshiba Corp | Solid-state image pickup device |
| JP2570264B2 (en) * | 1986-07-18 | 1997-01-08 | ソニー株式会社 | Solid-state imaging device |
-
1987
- 1987-02-25 JP JP62040327A patent/JP2738679B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63208269A (en) | 1988-08-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100797278B1 (en) | Pixel with strained silicon layer for improving carrier mobility and blue response in imagers | |
| JP2701726B2 (en) | Solid-state imaging device | |
| JPH0567767A (en) | Solid-state image pick-up device and manufacture thereof | |
| US5401679A (en) | Method of manufacturing charge transfer device | |
| JP2738679B2 (en) | Solid-state imaging device | |
| US5246875A (en) | Method of making charge coupled device image sensor | |
| JP3339249B2 (en) | Method for manufacturing solid-state imaging device | |
| JP3036747B2 (en) | Method for manufacturing solid-state imaging device | |
| JPH069242B2 (en) | Solid-state image sensor and manufacturing method thereof | |
| JP2000150857A (en) | Solid-state imaging device and manufacture of it | |
| JPH06163971A (en) | Manufacture of solid-state image pickup device | |
| JPH10107249A (en) | Manufacture of solid image-pickup element | |
| JPH04354161A (en) | Solid-state image sensing element | |
| JP2877656B2 (en) | Method for manufacturing solid-state imaging device | |
| KR100272558B1 (en) | Method of fabricating solid state image device | |
| JP2003142676A (en) | Solid-state imaging device and method of manufacturing the same | |
| JPH05315591A (en) | Forming method of photoelectron readout part of ccd image sensor | |
| KR100327430B1 (en) | Method for fabricating solid state image sensor | |
| KR930012126B1 (en) | Ccd image sensor and fabricating method thereof | |
| JP3663832B2 (en) | Solid-state imaging device and manufacturing method thereof | |
| JP2024072796A (en) | Image sensor and method of manufacturing the same | |
| JPS59202777A (en) | Solid-state image pickup device and its manufacture | |
| JPS61263155A (en) | Solid-state image pickup device and manufacture thereof | |
| JPS60173978A (en) | Solid-state image pickup device | |
| JPS6126256A (en) | Solid-state image pickup element |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313117 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| LAPS | Cancellation because of no payment of annual fees |