JPH0451983B2 - - Google Patents

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Publication number
JPH0451983B2
JPH0451983B2 JP56167208A JP16720881A JPH0451983B2 JP H0451983 B2 JPH0451983 B2 JP H0451983B2 JP 56167208 A JP56167208 A JP 56167208A JP 16720881 A JP16720881 A JP 16720881A JP H0451983 B2 JPH0451983 B2 JP H0451983B2
Authority
JP
Japan
Prior art keywords
receiving element
film
conductive layer
light
type conductive
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 - Lifetime
Application number
JP56167208A
Other languages
Japanese (ja)
Other versions
JPS5868965A (en
Inventor
Yasuo Tanaka
Toshihisa Tsukada
Akira Sasano
Taiji Shimomoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP56167208A priority Critical patent/JPS5868965A/en
Priority to US06/357,076 priority patent/US4412900A/en
Priority to DE8282301284T priority patent/DE3276889D1/en
Priority to EP82301284A priority patent/EP0060699B1/en
Priority to CA000398275A priority patent/CA1168739A/en
Priority to KR8201078A priority patent/KR860000160B1/en
Publication of JPS5868965A publication Critical patent/JPS5868965A/en
Publication of JPH0451983B2 publication Critical patent/JPH0451983B2/ja
Granted legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices 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; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/08—Semiconductor devices 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; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
    • H01L31/10—Semiconductor devices 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; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
    • H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
    • H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
    • H01L31/105—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the PIN type
    • H01L31/1055—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the PIN type the devices comprising amorphous materials of Group IV of the Periodic Table

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  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Solid State Image Pick-Up Elements (AREA)
  • Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
  • Photovoltaic Devices (AREA)
  • Light Receiving Elements (AREA)

Description

【発明の詳細な説明】 本発明は基板上に形成された下部電極とシリコ
ンを主体とし水素を含有する非晶質材料よりなる
光導電膜とスパツタリングにより形成した透明電
極とよりなる受光素子の製造方法に関するもので
ある。たとえば、絶縁性基板上に一次元に配列さ
れた非透光性金属電極を有し、該金属電極上に一
対一に対応するようにシリコンを主体とし水素を
含有する非晶質材料を基板側からn+型導電層、
ｉもしくはｎ型導電層、ｐ型導電層（以下、非晶
質水素化シリコンホトダイオードと呼ぶ）の順に
形成せしめた光導電体層および該光導電体層上に
一対一に対応するように透明電極を積層した低電
圧駆動の一次元光センサの製造方法に適用して有
用である。また、走査用Si−IC基板上に上記非晶
質水素化シリコンホトダイオードよりなる光導電
体層および透明電極を積層した低電圧駆動の固体
撮像素子の製造方法に適用しても有用である。ま
た、太陽電池など上記の構造の他の受光素子にも
適用できることは勿論のことである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the manufacture of a light-receiving element comprising a lower electrode formed on a substrate, a photoconductive film made of an amorphous material mainly composed of silicon and containing hydrogen, and a transparent electrode formed by sputtering. It is about the method. For example, non-transparent metal electrodes are arranged one-dimensionally on an insulating substrate, and an amorphous material mainly composed of silicon and containing hydrogen is placed on the substrate side in one-to-one correspondence on the metal electrodes. from n + type conductive layer,
A photoconductor layer formed in this order of an i- or n-type conductive layer and a p-type conductive layer (hereinafter referred to as an amorphous hydrogenated silicon photodiode), and transparent electrodes in one-to-one correspondence on the photoconductor layer. The present invention is useful when applied to a method for manufacturing a one-dimensional optical sensor driven by a low voltage and laminated. It is also useful to apply the present invention to a method of manufacturing a low-voltage-driven solid-state imaging device in which a photoconductor layer made of the amorphous hydrogenated silicon photodiode and a transparent electrode are laminated on a scanning Si-IC substrate. It goes without saying that the present invention can also be applied to other light-receiving elements having the above structure, such as solar cells.

本発明の方法は非晶質水素化シリコンホトダイ
オードよりなる光導電体層および透明電極を形成
した後に用いて有用なものである。 The method of the present invention is useful after forming a photoconductor layer and transparent electrode comprising an amorphous hydrogenated silicon photodiode.

前述の一次元光センサの例は光電変換機能及び
信号蓄積機能を有する固体素子を複数個一次元状
に配置し、各固体素子を一画素に対応させて一次
元の光信号読み取り素子列を形成し、この素子例
内で各固体素子を順次走査することにより外部に
一次元の画像情報を電気信号に変換する素子であ
り、特に、透明電極が光導電体層を覆うように形
成されてなる。 In the example of the one-dimensional optical sensor mentioned above, a plurality of solid-state elements having a photoelectric conversion function and a signal accumulation function are arranged in a one-dimensional manner, and each solid-state element corresponds to one pixel to form a one-dimensional optical signal reading element array. This device converts one-dimensional image information into an electrical signal by sequentially scanning each solid-state device within this device example, and in particular, it is a device in which a transparent electrode is formed to cover a photoconductor layer. .

この様な透明電極が光導電体層を覆うように形
成されてなる一次元光センサはこれまで報告され
ている。以下この技術を第１図ａ，ｂにその断面
図および平面図を示した一次元センサを用いて簡
単に説明する。第１図に示すように絶縁性基板１
上に非透光性金属電極２が形成され、さらに電極
２上に非晶質水素化シリコンホトダイオード３お
よび非晶質水素化シリコン分離ダイオード４が形
成される。この時、ダイオード３および４は金属
２１側からn+型導電層３１，４１、ｉもしくは
ｎ型導電層３２，４２、ｐ型導電層３３，４３の
順に形成されている。ホトダイオード３および分
離ダイオード４は通常同時に形成される。ホトダ
イオード３は絶縁層５の所望の位置にあけられた
コンタクト穴６２を介して透明電極７と電気的に
接続し、透明電極７はコンタクト穴６２を介して
２層配線用金属電極２２へ接続され、さらにコン
タクト穴６４を介して金属配線８１から行駆動用
ICへと接続されている。一方、分離ダイオード
４はホトダイオード３と共通の電極２１で接続
し、もう一方はコンタクト穴６１を介して金属配
線８２から列駆動用ICへと接続されている。第
１図に即して動作原理を説明すると、入射光１０
が透明電極７を通してホトダイオード３に達す
る。ここで光は吸収されて電子正孔対を生じ、こ
れらのキヤリアはホトダイオードに印加された逆
バイアス電圧VTにより金属電極２１に蓄積され
る。この時、分離ダイオードは逆方向にバイアス
されており配線８２とはOFF状態になつている。
蓄積されたキヤリアは同じ金属電極２１上に設け
られた分離ダイオード４を順方向にバイアスして
ON状態とし配線８２を通して蓄積されたキヤリ
アが外部に読み出される。上記の積層および読み
出し動作を列駆動ICを用いて配線８２を選択し、
行駆動ICを用いて配線８１を選択するマトリク
ス駆動で各ホトダイオードごとに順次行なうこと
により、一次元の画像情報を外部にとり出すこと
が出来る。本構造の一次元光センサは全画素を連
続した複数の群に分け、群ごとをまとめて走査す
るため、走査回路を大巾に簡単化することができ
る。また、ホトダイオード７と分離ダイオードを
同一のプロセスで形成できるので、従来のSi−IC
プロセスで作製したホトダイオードアレイを実装
したものよりも、作成プロセスが簡略化されてい
る。 A one-dimensional optical sensor in which such a transparent electrode is formed to cover a photoconductor layer has been reported so far. This technique will be briefly explained below using a one-dimensional sensor whose cross-sectional view and plan view are shown in FIGS. 1a and 1b. As shown in FIG.
A non-transparent metal electrode 2 is formed thereon, and an amorphous hydrogenated silicon photodiode 3 and an amorphous hydrogenated silicon isolation diode 4 are further formed on the electrode 2 . At this time, the diodes 3 and 4 are formed in this order from the metal 21 side: n + type conductive layers 31 and 41, i or n type conductive layers 32 and 42, and p type conductive layers 33 and 43. Photodiode 3 and isolation diode 4 are usually formed at the same time. The photodiode 3 is electrically connected to the transparent electrode 7 through a contact hole 62 formed at a desired position in the insulating layer 5, and the transparent electrode 7 is connected to the metal electrode 22 for two-layer wiring through the contact hole 62. , and further from the metal wiring 81 through the contact hole 64 for row driving.
Connected to IC. On the other hand, the separation diode 4 is connected to the photodiode 3 through a common electrode 21, and the other side is connected through a contact hole 61 from a metal wiring 82 to a column driving IC. To explain the operating principle based on FIG. 1, the incident light 10
reaches the photodiode 3 through the transparent electrode 7. Here, the light is absorbed to produce electron-hole pairs, and these carriers are accumulated in the metal electrode 21 by the reverse bias voltage V T applied to the photodiode. At this time, the separation diode is biased in the opposite direction and is in an OFF state with respect to the wiring 82.
The accumulated carriers forward bias the isolation diode 4 provided on the same metal electrode 21.
The carrier stored in the ON state is read out to the outside through the wiring 82. The above stacking and readout operations are performed by selecting the wiring 82 using a column drive IC,
One-dimensional image information can be extracted to the outside by sequentially performing matrix driving for each photodiode to select the wiring 81 using a row driving IC. The one-dimensional optical sensor with this structure divides all pixels into a plurality of consecutive groups and scans each group together, so the scanning circuit can be greatly simplified. In addition, since the photodiode 7 and the isolation diode can be formed in the same process, it is possible to form the photodiode 7 and the isolation diode in the same process.
The fabrication process is simpler than one that implements a photodiode array fabricated by a process.

しかし、基板１上に所望のパターンの電極２１
および非晶質水素化シリコンよりなるホトダイオ
ード３を形成した後、その上部に酸化インジウム
−酸化錫系の透明電極または白金などの半透明電
極をスパツタリング法により形成するとホトダイ
オードの光応答特性が劣化するという欠点が生じ
た。 However, if the desired pattern of electrodes 21 on the substrate 1 is
After forming the photodiode 3 made of amorphous hydrogenated silicon, it is said that if a transparent electrode made of indium oxide-tin oxide or a translucent electrode made of platinum is formed on top of the photodiode 3 by sputtering, the photoresponse characteristics of the photodiode will deteriorate. A shortcoming occurred.

光導電膜上にたとえば酸化インジウム−酸化錫
系金属酸化物の透明電極または金および白金など
の半透明金属電極をスパツタリング法により形成
するのは、非晶質水素化シリコンよりなるホトダ
イオードとの接着性を高めるためである。この問
題は特に上記の一次元光センサにおいて特に要求
される点である。 A transparent electrode made of indium oxide-tin oxide metal oxide or a semi-transparent metal electrode made of gold or platinum is formed on the photoconductive film by sputtering to improve its adhesion with the photodiode made of amorphous silicon hydride. This is to increase the This problem is particularly required in the above-mentioned one-dimensional optical sensor.

真空蒸着法で酸化物の透明電極または金属の半
透明電極を形成することも可能であるが、一般に
蒸着法で形成した膜はスパツタリング法で形成し
た膜よりも下地膜との接着性が劣つている。 It is also possible to form transparent oxide electrodes or translucent metal electrodes by vacuum evaporation, but films formed by evaporation generally have poorer adhesion to the underlying film than films formed by sputtering. There is.

第１図ａにその画素部の断面図を示した一次元
光センサはフアクシミリ用一次元光センサはフア
クシミリ用一次元光センサとして用いる場合、原
稿が上記センサと密着して移動するため透明電極
の上部およびその他のセンサ表面に摩耗防止用の
透明な保護層を形成する必要がある。あるいは保
護層のかわりに解像力を失わない程度に十分薄い
ガラス板を透明な接着剤ではり合わせて用いる必
要がある。この保護層を形成する工程を行う際、
上記ホトダイオード３と透明電極７との接着性が
弱いと透明電極７が剥離するという問題がしばし
ば発生する。この点で真空蒸着法で透明電極７を
形成するよりはスパツタリングで透明電極７を形
成することが望ましい。 When the one-dimensional optical sensor for facsimile is used as a one-dimensional optical sensor for facsimile, the cross-sectional view of the pixel part is shown in Fig. 1a, the document moves in close contact with the sensor, so the transparent electrode It is necessary to form a transparent protective layer on the top and other sensor surfaces to prevent wear. Alternatively, in place of the protective layer, it is necessary to use glass plates that are sufficiently thin so as not to lose resolution and are glued together with a transparent adhesive. When performing the process of forming this protective layer,
If the adhesiveness between the photodiode 3 and the transparent electrode 7 is weak, a problem often occurs in which the transparent electrode 7 peels off. In this respect, it is preferable to form the transparent electrode 7 by sputtering rather than by vacuum evaporation.

また、酸化インジウム−酸化錫系の透明電極を
インジウム−錫系のハロゲン化物あるいは有機金
属塩を用いたCVD（Chemical Vapor
Deposition）法により作成する方法も知られてい
る。しかし、この方法では比抵抗が低く、抵抗の
経時変化などもなく、かつ、下地膜との接着性の
良い膜を得るためには基板温度を3000℃以上にし
なければならない。一方、非晶質水素化シリコン
よりなる光導電膜は300℃以上に加熱すると可視
光領域での光感度が著しく低下する。従つて、非
晶質水素化シリコンホトダイオードを光導電膜と
して用いた一次元光センサ用の透明電極はCVD
法により作成することはできない。 In addition, indium oxide-tin oxide-based transparent electrodes can be coated with chemical vapor deposition (CVD) using indium-tin halides or organometallic salts.
A method of creating the image using the deposition method is also known. However, in this method, in order to obtain a film with low specific resistance, no change in resistance over time, and good adhesion to the underlying film, the substrate temperature must be raised to 3000° C. or higher. On the other hand, when a photoconductive film made of amorphous hydrogenated silicon is heated to 300° C. or higher, its photosensitivity in the visible light region decreases significantly. Therefore, a transparent electrode for a one-dimensional optical sensor using an amorphous hydrogenated silicon photodiode as a photoconductive film is a CVD method.
It cannot be created by law.

第１図に示した一次元光センサでは光信号電荷
を一定の蓄積時間（例えば、3ms）ホトダイオー
ド３内に蓄積した後、極めて短い時間（例えば、
500ns〜10ns）内に分離ダイオード４を順方向に
バイアスしてON状態として配線８２を通して読
み出す方式（蓄積動作方式を呼ぶ）をとつてい
る。 In the one-dimensional optical sensor shown in FIG.
The isolation diode 4 is biased in the forward direction within 500 ns to 10 ns) to be turned on and read out through the wiring 82 (referred to as an accumulation operation method).

第２図の受光素子は光応答特性を測定するため
のテスト用受光素子である。基板１１上に設けら
れた下部電極１２と非晶質水素化シリコンよりな
るホトダイオード１３と透明電極１４で構成され
ており、光導電膜には常に一定の逆バイアス電圧
VTが印加されていて、光パルス１５によりホト
ダイオード１３に発生した光電荷を電流計１６で
直接読みとることができる。ここで、１３１は
n+型導電層、１３２はｉもしくはｎ型導電層、
１３３はｐ型導電層である。スパツタリング法で
透明電極を形成した第２図の受光素子の光応答特
性は一例を示すと第３図のようになる。第３図に
おいて、特性ａは入射の光パルス、曲線ｂはホト
ダイオード１３に逆バイアスすなわち透明電極側
を負にバイアス（一般にVT＝０〜−10V程度を
使用する。）した場合の光応答特性を示す。第３
図の特性曲線より特に透明電極側に負のバイアス
を印加した場合光応答特性が著しく劣つているこ
とがわかる。すなわち、第３図では透明電極側を
負にして光パルスを照射すると透明電極から負電
荷が注入される現象（二次光電流とも呼ぶ）が起
つて、光をOFFにした後も、減衰電流が長い時
間にわたつて多く流れ、なかなか暗電流のレベル
までもどらないことを示している。この現象は一
次元光センサでは副走査方向（原稿送り方向）の
再生画像のパターン巾の拡大または縮少現象とし
て現われる。極端な場合は再生画像が全く得られ
ないこともある。また、二次光電流が支配的な光
応答特性は時定数が数十ms以上と大きめ、この
ような受光素子を用いると高速のフアクシミリ装
置を実現することが困難である。以上述べたよう
な現象は一次元光センサにとつて実用上極めて大
きな欠点でる。 The light-receiving element shown in FIG. 2 is a test light-receiving element for measuring optical response characteristics. It consists of a lower electrode 12 provided on a substrate 11, a photodiode 13 made of amorphous hydrogenated silicon, and a transparent electrode 14, and a constant reverse bias voltage is always applied to the photoconductive film.
V T is being applied, and the photocharge generated in the photodiode 13 by the optical pulse 15 can be directly read with an ammeter 16 . Here, 131 is
n + type conductive layer, 132 is i or n type conductive layer,
133 is a p-type conductive layer. An example of the photoresponse characteristics of the light-receiving element shown in FIG. 2 in which transparent electrodes are formed by sputtering is as shown in FIG. 3. In Fig. 3, the characteristic a is the incident light pulse, and the curve b is the photoresponse characteristic when the photodiode 13 is reverse biased, that is, the transparent electrode side is negatively biased (generally, V T =0 to -10 V is used). shows. Third
It can be seen from the characteristic curve in the figure that the photoresponse characteristics are significantly inferior, especially when a negative bias is applied to the transparent electrode side. In other words, in Figure 3, when a light pulse is irradiated with the transparent electrode side negative, a phenomenon in which negative charges are injected from the transparent electrode (also called secondary photocurrent) occurs, and even after the light is turned off, the decay current continues. This shows that a large amount of current flows over a long period of time, and that it does not return to the dark current level. In a one-dimensional optical sensor, this phenomenon appears as an expansion or contraction of the pattern width of a reproduced image in the sub-scanning direction (original feeding direction). In extreme cases, a reproduced image may not be obtained at all. Furthermore, the photoresponse characteristic in which secondary photocurrent is dominant has a large time constant of several tens of milliseconds or more, and it is difficult to realize a high-speed facsimile device using such a light receiving element. The above-mentioned phenomenon is an extremely serious practical drawback for one-dimensional optical sensors.

上述の欠点を除去した非晶質水素化シリコンホ
トダイオードを用いた一次元光センサを得るため
に本発明に極めて有効である。 The present invention is extremely effective in obtaining a one-dimensional optical sensor using an amorphous hydrogenated silicon photodiode which eliminates the above-mentioned drawbacks.

本発明は上記目的を達成するために、所望の配
線がなされた基板上に水素を含有するシリコンを
主体として非晶質光導電膜を反応性スパツタリン
グ法またはグロー放電CVD法により形成した後、
上記光導電膜上に透明電極をスパツタリング法に
基板側からn+型導電層、ｉまたはｎ型導電層、
ｐ型導電層の順に形成する。しかる後に、本一次
元光センサを170℃から250℃の温度範囲で熱処理
し、透明電極をスパツタリング法にて光導電膜上
に形成したために生じた本固体撮像素子の光応答
特性の劣化を改良するものである。本発明によつ
て本一次元光センサの長所であう光応答特性が良
好でしかも感度が高い低電圧駆動の素子を得るこ
とが出来、高速のフアクシミリ装置を実現するこ
とができる。また、n+型導電層、ｉ型もしくは
ｎ型導電層、ｐ型導電層、透明電極の順に堆積し
てホトダイオードとして用いる理由を述べると、
入射光はその大部分が透明電極近傍で吸収されホ
トキヤリアを発生するが、発生した電子一正孔対
のうち電子の光導電膜中の走行性が優れているの
で、ホトダイオードを逆バイアスして用いる場
合、電子が透明電極側から金属電極側へ移動する
ような構造にした方が有利だからである。前記光
導電膜の反応性スパツタリング法としては、一般
のスパツタリング装置を用いてもよいし、マグネ
トロン型の高速スパツタ装置も用いることもでき
る。スパツタ装置内の対向電極の一方の陰極（タ
ーゲツト側電極に多結晶シリコンをスパツタ用タ
ーゲツトとして設置し、他方の陽極（基板側電
極）には所望の配線がなされた一次元光センサ用
基板を設置する。スパツタ室内を１×10-5Torr
以下の高真空に保ちながら250〜300℃に加熱し
て、スパツタ室内の脱ガスを行つた後、放電ガス
として水素とアルゴンの如き希ガスおよび微量の
ドーピングガスとの混合ガスをスパツタ室内に導
入し、13.56MHzの高周波スパツタリングを行つ
て、上記の基板上に水素を含有したシリコンを主
体とする非晶質光導電膜を堆積せしめる。膜形成
中の基板温度は100〜350℃、放電ガスの圧力は８
×10-4Torr〜２×10-2Torr、放電ガス中の水素
ガスの組織は10〜60mol％の範囲内である。光導
電膜堆積中において上記のアルゴンと水素の混合
ガス中にドーピングガスとして微量の窒素ガスを
0.01％〜１％程度混入させるか或いは微量の水素
化リン例えばホスフイン（PH3）を０，01〜５％
程度混入させるとn+型導電層が得られ、また上
記アルゴンと水素の混合ガスに微量の水素化ホウ
素例えばジボラン（B2H6）を0.01〜５％程度混
入させればｐ型導電層が得られる。これらのドー
ピングガスの添加を行なわない場合は一般にｉま
たはｎ型の導電層が得られる。以上のスパツタ条
件を用いて、n+型導電層、ｉまたはｎ型導電層、
ｐ型導電層の順に光導電膜を堆積し、ホトダイオ
ードおよび分離ダイオード用の導電膜とする。 In order to achieve the above object, the present invention forms an amorphous photoconductive film mainly made of hydrogen-containing silicon on a substrate with desired wiring by a reactive sputtering method or a glow discharge CVD method.
A transparent electrode is sputtered onto the photoconductive film, starting from the substrate side with an n + type conductive layer, an i or n type conductive layer,
A p-type conductive layer is formed in this order. Afterwards, this one-dimensional optical sensor was heat-treated in a temperature range of 170°C to 250°C to improve the deterioration of the photoresponse characteristics of this solid-state image sensor that occurred due to the transparent electrode being formed on the photoconductive film by sputtering method. It is something to do. According to the present invention, it is possible to obtain a low-voltage driven element that has good photoresponse characteristics, which are the advantages of the present one-dimensional optical sensor, and has high sensitivity, thereby making it possible to realize a high-speed facsimile device. Also, the reason why a photodiode is used by depositing an n + type conductive layer, an i type or n type conductive layer, a p type conductive layer, and a transparent electrode in this order is as follows.
Most of the incident light is absorbed near the transparent electrode and generates photocarriers, but among the generated electron-hole pairs, the electrons have excellent mobility in the photoconductive film, so the photodiode is used with a reverse bias. In this case, it is advantageous to have a structure in which electrons move from the transparent electrode side to the metal electrode side. For the reactive sputtering method of the photoconductive film, a general sputtering device or a magnetron-type high-speed sputtering device can also be used. Polycrystalline silicon is installed as a sputtering target on one cathode (target side electrode) of the opposing electrodes in the sputtering device, and a one-dimensional optical sensor substrate with desired wiring is installed on the other anode (substrate side electrode). 1×10 -5 Torr in the spatuta room.
After degassing the sputtering chamber by heating it to 250-300℃ while maintaining the following high vacuum, a mixed gas of hydrogen, a rare gas such as argon, and a trace amount of doping gas is introduced into the sputtering chamber as a discharge gas. Then, by performing high frequency sputtering at 13.56 MHz, an amorphous photoconductive film mainly composed of silicon containing hydrogen is deposited on the above substrate. The substrate temperature during film formation was 100 to 350℃, and the discharge gas pressure was 8℃.
×10 −4 Torr to 2×10 −2 Torr, and the structure of hydrogen gas in the discharge gas is within the range of 10 to 60 mol%. During deposition of the photoconductive film, a small amount of nitrogen gas is added as a doping gas to the above-mentioned argon and hydrogen mixture gas.
Mix about 0.01% to 1% or add a trace amount of phosphorus hydride such as phosphine (PH 3 ) to 0.01 to 5%.
If a small amount of boron hydride, such as diborane (B 2 H 6 ), is mixed in the above mixed gas of argon and hydrogen in an amount of about 0.01 to 5%, a p-type conductive layer can be obtained. can get. If these doping gases are not added, an i- or n-type conductive layer is generally obtained. Using the above sputtering conditions, an n + type conductive layer, an i or n type conductive layer,
A photoconductive film is deposited in the order of the p-type conductive layer to form a conductive film for a photodiode and a separation diode.

また、前記のグロー放電CVD（Chemical
Vapror Deposition）法としては、rfコイル法と
二極放電法の二種類がある。いずれも、放電ガス
としてSiH4などのシラン系ガスとアルゴンの如
き希ガスあるいは水素ガスとの混合ガスを用い、
グロー放電を行つてシラン系ガスの分解反応によ
り上記一次元光センサ用基板上に水素を含有した
シリコンを主体とする非晶質光導電膜を堆積せし
める方法であり、シリコンに水素を添加する反応
を利用する反応性スパツタリング法と区別され
る。rfコイル法は反応室をrfコイル中におき、rf
コイルに13.56MHzの高周波を印加して、反応室
内に導入したSiH4およびアルゴンの混合ガスの
グロー放電を起こさせ、反応室内に設置した上記
一次元光センサ用基板上に水素を含有したシリコ
ンを主体とする非晶質光導電膜を堆積せしめる方
法である。また、二極放電法は通常のスパツタリ
ング装置を用いて、対向電極間に13.56MHzの高
周波を印加して反応室内に導入したSiH4および
アルゴンあるいは水素の混合ガスのグロー放電を
起こさせ、反応室内に設置した上記一次元光セン
サ用基板上に水素を含有したシリコンを主体とす
る非晶質光導電膜を堆積せしめる方法である。膜
形成中の基板温度は100〜300℃、放電ガスの圧力
は反応性スパツタリング法より高く５×10-2
Torrから2Torr、放電ガス中のSiH4ガスの組成
は５〜40mol％の範囲内である。 In addition, the glow discharge CVD (Chemical
There are two types of Vapror Deposition methods: the RF coil method and the bipolar discharge method. In both cases, a mixed gas of silane gas such as SiH 4 and rare gas such as argon or hydrogen gas is used as the discharge gas.
This is a method of depositing an amorphous photoconductive film mainly made of silicon containing hydrogen on the one-dimensional optical sensor substrate through a decomposition reaction of silane-based gas by performing glow discharge. It is distinguished from the reactive sputtering method, which uses The rf coil method places the reaction chamber inside an rf coil, and
A high frequency of 13.56MHz was applied to the coil to cause a glow discharge of the mixed gas of SiH 4 and argon introduced into the reaction chamber, and silicon containing hydrogen was placed on the substrate for the one-dimensional optical sensor installed in the reaction chamber. This is a method in which an amorphous photoconductive film is mainly deposited. In addition, in the bipolar discharge method, a 13.56 MHz high frequency is applied between opposing electrodes using a normal sputtering device to cause a glow discharge of a mixed gas of SiH 4 and argon or hydrogen introduced into the reaction chamber. In this method, an amorphous photoconductive film mainly composed of hydrogen-containing silicon is deposited on the one-dimensional optical sensor substrate placed on the substrate. The substrate temperature during film formation is 100 to 300℃, and the discharge gas pressure is 5×10 -2 , which is higher than the reactive sputtering method.
Torr to 2 Torr, the composition of SiH 4 gas in the discharge gas is within the range of 5 to 40 mol%.

光導電膜堆積中において、スパツタリング法の
場合と同様に、上記SiH4およびアルゴンあるい
は水素の混合ガス中にドーピングガスとして微量
の水素化リン例えばホスフイン（PH3）を0.01〜
５％程度混入させるとn+型導電層が得られ、ま
た上記のSiH4およびアルゴンあるいは水素の混
合ガス中にドーピングガスとして微量の水素化ホ
ウ素例えばジボラン（B2H6）を0.01〜５％程度
混入させればｐ型導電層が得られる。これらのド
ーピングガスの添加を行なわない場合は一般にｎ
またはｉ型の導電層が得られる。以上のグロー放
電CVD条件を用いて、n+型導電層、ｉまたはｎ
型導電層、ｐ型導電層の順に光導電膜を堆積し、
ホトダイオードおよび分離ダイオード用の導電膜
とする。 During photoconductive film deposition, as in the case of the sputtering method, a trace amount of phosphorus hydride, such as phosphine (PH 3 ), is added as a doping gas to the mixed gas of SiH 4 and argon or hydrogen from 0.01 to 0.01.
When about 5% is mixed in, an n + type conductive layer is obtained, and a trace amount of boron hydride, such as diborane (B 2 H 6 ), is added as a doping gas to the above mixed gas of SiH 4 and argon or hydrogen at 0.01 to 5%. If a certain amount is mixed in, a p-type conductive layer can be obtained. If these doping gases are not added, generally n
Alternatively, an i-type conductive layer can be obtained. Using the above glow discharge CVD conditions, the n + type conductive layer, i or n
depositing a photoconductive film in the order of a type conductive layer and a p-type conductive layer,
Conductive film for photodiodes and isolation diodes.

上記の方法で一次元センサ用上に非晶質水素化
シリコンよりなる導電膜を形成した後、上記導電
膜を所望のパターンに加工するとホトダイオード
および分離ダイオードの素子列が完成される。さ
らに、絶縁を所望のパターンに形成した後、その
上部に透明電極をスパツタリング法により形成す
る。この透明電極としては(1)酸化インジウム、酸
化錫およびそれらの混合物から選ばれた一つを主
成分とする透明電極が用いられる。また、(2)金、
白金、タンタル、モリブデン、アルミニウム、ク
ロム、ニツケルおよびそれらの混合物からなる群
から選ばれた一つの主成分とする半透明状の金属
電極を用いることもできる。 After forming a conductive film made of amorphous hydrogenated silicon on a one-dimensional sensor using the above method, the conductive film is processed into a desired pattern to complete an element array of photodiodes and separation diodes. Further, after forming the insulation into a desired pattern, a transparent electrode is formed on the insulation by sputtering. As this transparent electrode, a transparent electrode whose main component is (1) one selected from indium oxide, tin oxide, and a mixture thereof is used. Also, (2) gold;
It is also possible to use translucent metal electrodes having one main component selected from the group consisting of platinum, tantalum, molybdenum, aluminum, chromium, nickel, and mixtures thereof.

(1)の透明電極を形成するには、インジウム−錫
系の金属をターゲツトとして、酸化ガスを含有し
たアルゴンガス中で反応性RFスパツタリングを
行なう方法もあるが、通常は、酸化インジウム−
酸化錫系の焼結体ターゲツトを用いて、アルゴン
ガスなどの希ガス中で、RFスパツタリングを行
なう方法がとられる。この場合、スパツタ装置内
の対向電極の一方の陰極（ターゲツト側電極）に
酸化インジウム−酸化錫系の結晶体をスパツタ用
ターゲツトとして設置し、他方の陽極（基板側電
極）には非晶質水素化シリコンよりなる光導電膜
を堆積した一次元光センサ用基板を設置する。ス
パツタ室内を５×10-6Torr以下の高真空にまで
排気した後、放電ガスとしてアルゴンの如き希ガ
スをスパツタ室内に導入し、13.56MHzの高周波
スパツタリングを行つて、上記光導電膜上に所定
のパターンの酸化インジウム−酸化錫系の透明電
極を堆積せしめる。膜形成中の基板温度は80℃〜
220℃、放電ガスの圧力は３×10-3Torrから５×
10-2Torrである。このようにして、透明電極を
形成しこれを所望のパターンに加工し、二層配線
用金属配線を所望のパターンに設けると第１図に
示す如き形状の一次元光センサが得られる。 In order to form the transparent electrode (1), there is a method of performing reactive RF sputtering in argon gas containing oxidizing gas using an indium-tin metal as a target, but usually indium oxide-tin metal is used as a target.
A method is used in which RF sputtering is performed using a tin oxide-based sintered target in a rare gas such as argon gas. In this case, an indium oxide-tin oxide crystal is installed as a sputtering target on one cathode (target side electrode) of the opposing electrodes in the sputtering device, and amorphous hydrogen is placed on the other anode (substrate side electrode). A one-dimensional photosensor substrate on which a photoconductive film made of silicon oxide is deposited is installed. After evacuating the sputtering chamber to a high vacuum of 5×10 -6 Torr or less, a rare gas such as argon is introduced into the sputtering chamber as a discharge gas, and high frequency sputtering at 13.56MHz is performed to form a predetermined sputtering layer on the photoconductive film. An indium oxide-tin oxide based transparent electrode is deposited in a pattern of: Substrate temperature during film formation is 80℃ ~
220℃, discharge gas pressure from 3×10 -3 Torr to 5×
10 -2 Torr. In this way, a transparent electrode is formed and processed into a desired pattern, and a two-layer metal wiring is provided in a desired pattern to obtain a one-dimensional optical sensor having a shape as shown in FIG. 1.

また、(2)の透明電極に関しても、スパツタ装置
内の陰極（ターゲツト側電極）に、金、白金、タ
ンタル、モリブデン、アルミニウム、クロム、ニ
ツケルおよびそれらの混合物からなる群から選ば
れた一つを主成分とする金属をスパツタ用ターゲ
ツトとして配置すれば上記の(1)の透明電極と同様
のスパツタリング法により半透明状の金属電極を
堆積することができる。この場合、半透明金属電
極は光透過性を良くするためにできるだけ膜厚を
薄くする必要がある。通常、その膜厚は400Å以
下である。 Regarding the transparent electrode (2), one selected from the group consisting of gold, platinum, tantalum, molybdenum, aluminum, chromium, nickel, and mixtures thereof is used as the cathode (target side electrode) in the sputtering device. If the main component metal is placed as a sputtering target, a translucent metal electrode can be deposited by the same sputtering method as for the transparent electrode in (1) above. In this case, the thickness of the semi-transparent metal electrode must be made as thin as possible to improve light transmittance. Usually, the film thickness is 400 Å or less.

以上述べた方法で得られた固体撮像素子は第３
図で説明した如く、光応答特性の劣化した素子で
ある。特に、第１図において透明電極７に負のバ
イアス電圧VTを印加した場合、二次光電流が支
配的な光応答特性を示し、光応答の時定数が大き
くなつている。しかし、この素子を170℃〜250℃
の間で約15分程度から数時間熱処理すると、光応
答の遅さは全く問題とならない程度にまで改善さ
れる。この改善のされ方は第２図に示した受光素
子の光応答特性で表わすと、第４図にその一例を
示す如くとなる。第４図と第２図とを比較すると
光応答特性の改善のされ方が顕著であることがわ
かる。第５図は改善例の一例を光OFF後の減衰
電流で定量的に比べた図である。曲線ａは熱処理
前の減衰電流、曲線ｂは熱処理後の減衰電流を表
わしている。熱処理前は曲線ａに示ように、初期
値（光OFF直前の光電流）が大きく（光電利得
Ga＝４）、減衰の時定数τa＝30msと大きいいわゆ
る二次光電流が支配的な光応答特性を示してい
る。これに対して、熱処理後は曲線ｂに示すよう
に初期値の光電利得Gbは二次光電流が抑制され
るので１となるが、減衰の時定数τbは10μsと3000
分の１程度に改善されている。曲線ｂは測定回路
系の時定数を加算されているので、実際の改善巾
はさらに大きくなる。この現象は第１図に示した
一次元光センサでも全く同様に観測される。 The solid-state image sensor obtained by the method described above is
As explained in the figure, this is an element with deteriorated photoresponse characteristics. Particularly, when a negative bias voltage V T is applied to the transparent electrode 7 in FIG. 1, a photoresponse characteristic in which the secondary photocurrent is dominant is exhibited, and the time constant of the photoresponse becomes large. However, when this element is heated to 170℃~250℃
If heat treatment is performed for about 15 minutes to several hours between then, the slowness of the photoresponse will be improved to such an extent that it will not be a problem at all. This improvement can be expressed by the photoresponse characteristics of the light receiving element shown in FIG. 2, and an example thereof is shown in FIG. Comparing FIG. 4 with FIG. 2, it can be seen that the photoresponse characteristics have been significantly improved. FIG. 5 is a diagram quantitatively comparing an example of an improved example in terms of attenuation current after the light is turned off. Curve a represents the decay current before heat treatment, and curve b represents the decay current after heat treatment. Before heat treatment, as shown in curve a, the initial value (photocurrent just before the light is turned off) is large (photoelectric gain
G a =4), and a large attenuation time constant τ a =30 ms, showing a photoresponse characteristic dominated by a large so-called secondary photocurrent. On the other hand, after heat treatment, as shown in curve b, the initial value of photoelectric gain G b is 1 because the secondary photocurrent is suppressed, but the decay time constant τ b is 10 μs and 3000 μs.
It has been improved by about 1/2. Since the time constant of the measurement circuit system is added to curve b, the actual improvement range becomes even larger. This phenomenon is observed in exactly the same way with the one-dimensional optical sensor shown in FIG.

第１図に示した一次元光センサにおいて、熱処
理温度と、光OFF後3ms経過した時の残像
（減衰電流／初期電流）との関係は第６図に示す如くと
なつ た。但し、熱処理時間は60分間とした。第６図か
ら明らかなように、熱処理温度を室温から次第に
上げていくと、残像は次第に大きくなり、100〜
120℃の間で最大値を示した後、150℃前後から急
速に小さくなり170℃〜250℃で最小値を示して、
また反対に増加する傾向を持つ。熱処理時間は各
温度20〜60分でほぼその温度における残像の飽和
値に達する。従つて必要以上長時間熱処理をして
も具体的に余り意味はない。熱処理は通常大気中
で行うがアルゴンガスなどの希ガスあるいは窒素
などの不活性ガス中で行つても同様の効果が確認
できた。一般の一次元光センサでは3ms後の残像
が４％以下であれば十分に使用可能である。第６
図から少なくとも140℃以上でその効果を奏しは
じめるが170℃〜250℃の範囲で熱処理を行なえ
ば、第１図に示した一次元光センサはバイアス電
圧が−1Vで3ms後の残像が４％以下となり、一
次元光センサとした極めて好都合に使用できる。 In the one-dimensional optical sensor shown in FIG. 1, the relationship between the heat treatment temperature and the afterimage (attenuation current/initial current) 3 ms after the light was turned off was as shown in FIG. However, the heat treatment time was 60 minutes. As is clear from Fig. 6, as the heat treatment temperature is gradually raised from room temperature, the afterimage becomes larger and increases from 100 to
After showing the maximum value between 120℃, it rapidly decreases from around 150℃ and shows the minimum value between 170℃ and 250℃.
On the contrary, it tends to increase. The heat treatment time is 20 to 60 minutes at each temperature, and the saturation value of the afterimage is approximately reached at that temperature. Therefore, there is no particular point in carrying out heat treatment for a longer time than necessary. Heat treatment is normally performed in the atmosphere, but similar effects were confirmed even when heat treatment is performed in a rare gas such as argon gas or an inert gas such as nitrogen. A general one-dimensional optical sensor can be used sufficiently if the afterimage after 3 ms is 4% or less. 6th
As shown in the figure, the effect starts to appear at least above 140°C, but if heat treatment is performed in the range of 170°C to 250°C, the one-dimensional optical sensor shown in Fig. 1 has an afterimage of 4% after 3ms at a bias voltage of -1V. As a result, it can be used very conveniently as a one-dimensional optical sensor.

第５図および第６図で示した本発明の効果はあ
くまで、非晶質水素化シリコンよりなる第１図お
よび第２図に示したn+型導電層、ｉまたはｎ型
導電層、ｐ型導電層の順に堆積せしめたホトダイ
オード上にスパツタリング法により透明電極を堆
積することによつて発生したホトダイオードと透
明電極間の電気的接触の問題点を改善するもので
ある。非晶質水素化シリコンを前述の反応性スパ
ツタリング法もしくはグロー放電法により堆積直
後に光感度を大巾に向上する目的で光導電膜堆積
装置内に入れたまま真空中で220〜270℃に保持し
て熱処理する技術とは別異の技術である。 The effects of the present invention shown in FIGS. 5 and 6 are limited to the n + type conductive layer, i or n type conductive layer, and p type conductive layer shown in FIGS. The problem of electrical contact between the photodiode and the transparent electrode caused by depositing the transparent electrode by sputtering on the photodiode on which conductive layers have been sequentially deposited is improved. Immediately after amorphous hydrogenated silicon is deposited by the above-mentioned reactive sputtering method or glow discharge method, it is kept in a photoconductive film deposition apparatus at 220 to 270°C in vacuum for the purpose of greatly improving photosensitivity. This is a different technology from heat treatment.

また、本発明は第１図に一例として示した一次
元光センサのみならず、原理的に第２図に示した
如くの構成を持つ受光素子全般に対しても有効で
ある。例えば、太陽電池あるいは、二次元状に配
列したスイツチと上記スイツチを介して取り出し
た光学像に相当する光電荷を転送する走査素子を
少なくとも有する半導体基板（走査用si−IC基
板）上に非晶質水素化シリコンよりなる光導電膜
をn+型導電層、ｉ若しくはｎ型導電層、ｐ型導
電層の順に堆積せしめてホトダイオードとし、さ
らに、その上に透明電極をスパツタリング法によ
り堆積せしめてなるいわゆる二階建構造の固体撮
像素子に適用しても有用なことは勿論である。ま
た、ここで用いている非晶質水素化シリコンを主
体とすると光導電膜に適当量の炭素あるいはゲル
マニウムが含有されていても本発明は有効であ
る。 Further, the present invention is effective not only for the one-dimensional optical sensor shown as an example in FIG. 1, but also for general light-receiving elements having the structure shown in FIG. 2 in principle. For example, an amorphous crystal is formed on a solar cell or a semiconductor substrate (scanning si-IC substrate) having at least two-dimensionally arranged switches and a scanning element that transfers a photoelectric charge corresponding to an optical image taken out through the above-mentioned switch. A photoconductive film made of hydrogenated silicon is deposited in the order of an n + type conductive layer, an i or n type conductive layer, and a p type conductive layer to form a photodiode, and a transparent electrode is further deposited thereon by a sputtering method. Of course, the present invention is also useful when applied to a solid-state image sensor having a so-called two-story structure. Further, if the photoconductive film is mainly composed of amorphous hydrogenated silicon used here, the present invention is effective even if the photoconductive film contains an appropriate amount of carbon or germanium.

以下本発明を実施例により詳しく説明する。 The present invention will be explained in detail below with reference to Examples.

実施例 １ 第７図から第１１図までは本発明の一次元光セ
ンサの構造方法を示す画素部の断面図である。絶
縁性のガラス基板１上に金属クロムをスパツタリ
ング法により膜厚2000Å程度に堆積し、これを硝
酸第２セリウムアンモニウム系のエツチング液を
用いたホトエツチング工程により所望の電極パタ
ーン２とする（第７図）。ここで、２１はホトダ
イオードおよび分解ダイオード用電極、２２は二
層配線用下部電極である。次に、この基板を２極
式グロー放電CVD装置内に設置し、反応室内に
放電ガスとして10％SiH4ガスを含んだH2ガスを
1Torr導入し、ドーピングガスとしてPH3ガスを
体積比（PH3／SiH4）で１％になるように導入
して、13.56MHzの高周波放電を行うことにより
非晶質水素化シリコンを主体とするn+型導電層
を上記基板上に250Åの膜厚に堆積せしめる。さ
らに、PH3ガスの反応室内への供給を停止して10
％SiH4＋90％H2混合ガスのみにて高周波放電を
継続し、非晶質水素化シリコンを主体とするｉ型
導電層を5500Åの膜厚に堆積せしめる。さらに、
上記放電ガスに加えてドーピングガスとしてB2
H6ガスを体積比（B2H6／SiH4）で１％になるよ
うに導入して高周波放電を継続して非晶質シリコ
ンを主体とするｐ型導電層を400Åの膜厚に堆積
せしめる。このように形成したn+−ｉ−ｐ構造
の非晶質水素化シリコン膜をCH4ガスを用いたプ
ラズマエツチング法により所定の形状にパターン
化するホトダイオード３および分離ダイオード４
となる（第８図）。ここで、３１，４１はn+型導
電層、３２，４２はｉ型導電層、３３，４３はｐ
型導電層である。次に、上記基板上にコーニング
社製7059ガラスをスパツタリング法により膜厚
2μmの厚さに堆積せしめ、HF−HNO3−H2Ｏ系
のエツチング液を用いたホトエツチング法により
所定の場所にコンタクト穴６１，６２，６３，６
４をあけると二層配線用の絶縁膜５となる（第９
図）。次に、この上部にIn2O3−SnO2系の透明電
極をスパツタリング法で5000Åの膜厚に堆積す
る。この時、スパツタ用ターゲツトとしては、
SnO2を5mol％含有したIn2O3焼結体を陰極（カ
ソード）に設置して用いる。放電ガスとしてAr
ガスを用い１×10-2Torrのガス圧で13.56MHzの
高周波スパツタリングを行つた。透明電極形成
後、HCl−HNO4−H2Ｏ系のエツチング液を用
いたホトエツチング法により透明電極を所定の形
状７にパターン化すると第１０図に示す如き断面
構造の素子が得られる。上記の素子中のホトダイ
オード３は光応答特性が劣化しており、例えば、
第３図に示すような、二次光電流が支配的な光応
答速度の遅い素子である。次に、この素子を空気
中で225℃、60分間の熱処理を行うと、光応答速
度が第４図に示すように大巾に早くなり、特性の
改善ができた。次に、このパターン化されたITO
膜をホトレジストよりなる保護膜で完全に被覆し
た後、上記基板上に真空蒸着法によりAl膜を
2μmの膜厚に堆積せしめる。さらに、H2PO4−
HNO3−H2Ｏ系のエツチング液を用いたホトエ
ツチング法により二層配線用のAl電極パターン
８１，８２を形成する。この時、ITO膜はホトレ
ジで被覆されておりAlのエツチング液に触れる
ことによつて生ずる電気化学的なITO膜の溶出を
防いでいる。Al電極パターン形成後、ITOの保
護膜を酸素プラズマアツシヤ法により除去すると
第１１図に示す如く読み取り速度の早い一次元光
センサが得られる。この一次元光センサを用いる
と高速のフアクシミリを実現することができる。Embodiment 1 FIGS. 7 to 11 are cross-sectional views of a pixel portion showing a method of constructing a one-dimensional optical sensor of the present invention. Metallic chromium is deposited on an insulating glass substrate 1 to a thickness of about 2000 Å by sputtering, and this is formed into a desired electrode pattern 2 by a photoetching process using a ceric ammonium nitrate based etching solution (Fig. 7). ). Here, 21 is an electrode for a photodiode and a decomposition diode, and 22 is a lower electrode for a two-layer wiring. Next, this substrate was placed in a two-electrode glow discharge CVD device, and H2 gas containing 10% SiH4 gas was introduced into the reaction chamber as a discharge gas.
1 Torr, PH 3 gas as a doping gas at a volume ratio (PH 3 /SiH 4 ) of 1%, and a high frequency discharge of 13.56 MHz is performed to mainly form amorphous silicon hydride. An n + type conductive layer is deposited on the substrate to a thickness of 250 Å. Furthermore, the supply of PH3 gas into the reaction chamber was stopped for 10
High frequency discharge is continued using only a mixed gas of %SiH 4 +90%H 2 to deposit an i-type conductive layer mainly composed of amorphous hydrogenated silicon to a thickness of 5500 Å. moreover,
B2 as a doping gas in addition to the above discharge gas
Introducing H 6 gas at a volume ratio (B 2 H 6 /SiH 4 ) of 1% and continuing high-frequency discharge to deposit a p-type conductive layer mainly made of amorphous silicon to a thickness of 400 Å. urge A photodiode 3 and a separation diode 4 are patterned into a predetermined shape by a plasma etching method using CH 4 gas to pattern the thus formed amorphous hydrogenated silicon film having an n + -i-p structure.
(Figure 8). Here, 31 and 41 are n + type conductive layers, 32 and 42 are i type conductive layers, and 33 and 43 are p type conductive layers.
type conductive layer. Next, a film of Corning 7059 glass was coated on the above substrate using a sputtering method.
Contact holes 61, 62, 63, 6 are formed at predetermined locations by photo-etching using a HF-HNO 3 -H 2 O-based etching solution.
If 4 is opened, it becomes the insulating film 5 for two-layer wiring (9th
figure). Next, an In 2 O 3 --SnO 2 -based transparent electrode is deposited on top of this by sputtering to a thickness of 5000 Å. At this time, as a target for sputtering,
An In 2 O 3 sintered body containing 5 mol % of SnO 2 is used by installing it as a cathode. Ar as discharge gas
High frequency sputtering at 13.56MHz was performed using gas at a gas pressure of 1×10 -2 Torr. After forming the transparent electrode, the transparent electrode is patterned into a predetermined shape 7 by photoetching using an etching solution of HCl--HNO 4 --H 2 O-based, to obtain an element having a cross-sectional structure as shown in FIG. The photodiode 3 in the above device has deteriorated photoresponse characteristics, for example,
As shown in FIG. 3, this is an element with a slow photoresponse speed in which secondary photocurrent is dominant. Next, when this element was heat-treated in air at 225°C for 60 minutes, the optical response speed was greatly increased as shown in Figure 4, and the characteristics were improved. Then this patterned ITO
After completely covering the film with a protective film made of photoresist, an Al film is deposited on the above substrate by vacuum evaporation.
Deposit to a film thickness of 2 μm. Furthermore, H 2 PO 4 −
Al electrode patterns 81 and 82 for two-layer wiring are formed by photoetching using an HNO 3 --H 2 O-based etching solution. At this time, the ITO film is covered with photoresist to prevent electrochemical elution of the ITO film caused by contact with the Al etching solution. After forming the Al electrode pattern, the ITO protective film is removed by oxygen plasma ashing to obtain a one-dimensional optical sensor with a high reading speed as shown in FIG. Using this one-dimensional optical sensor, high-speed facsimile can be realized.

実施例 ２ また、本発明は太陽電池の製造方法に用いても
有効である。この場合、光応答特性の向上に加え
て、光照射時の非晶質水素化シリコンホトダイオ
ードの電圧−電流特性が改善される。Example 2 The present invention is also effective when used in a method of manufacturing a solar cell. In this case, in addition to improving the photoresponse characteristics, the voltage-current characteristics of the amorphous hydrogenated silicon photodiode upon irradiation with light are improved.

所望のステンレスステイール基板上に磁気テー
プ１と同様の方法でn+型およびｉ型導電層を形
成する。さらに、10％siH4＋90％H2混合ガスに
ドーピングガスとして、CH4ガスを体積比
（CH4／SiH4）で３％、B2H6／SiH4）で１％に
なるように添加し、高周波放電を継続して水素を
含んだ非晶質炭化珪素（ａ−SiC：Ｈ）を主体と
するｐ型導電層を350Åの膜厚に堆積せしめる。
次に、この上部にIn2O3−SnO2系の透明電極をス
パツタリング法により1000Åの膜厚に堆積する。
スパツタリング条件は実施例１と同様の条件で行
つた。このようにして第２図に示す如き断面構造
の太陽電池が得られた。しかし、この太陽電池は
特性が劣化しており、ほとんどホトダイオード特
性を示さない。例えば、第１２図の曲線ａに示す
ように、光照射時の開放端電圧（open circuit
voltago，Voc）および短絡電流（short circuit
current Ish）が小さい。次に、この素子を空気
中で230℃、20分間の熱処理を行なうと、電圧−
電流特性が大巾に改善され、第１２図の曲線ｂに
示すような良好な太陽電池の特性を得ることがで
きる。 N + type and i type conductive layers are formed on a desired stainless steel substrate in the same manner as magnetic tape 1. Furthermore, CH 4 gas was added as a doping gas to the 10% siH 4 + 90% H 2 mixed gas so that the volume ratio (CH 4 /SiH 4 ) was 3% and B 2 H 6 /SiH 4 ) was 1%. Then, high-frequency discharge is continued to deposit a p-type conductive layer mainly composed of hydrogen-containing amorphous silicon carbide (a-SiC:H) to a thickness of 350 Å.
Next, an In 2 O 3 --SnO 2 -based transparent electrode is deposited on top of this by sputtering to a thickness of 1000 Å.
The sputtering conditions were the same as in Example 1. In this way, a solar cell having a cross-sectional structure as shown in FIG. 2 was obtained. However, the characteristics of this solar cell have deteriorated, and it hardly exhibits photodiode characteristics. For example, as shown in curve a in FIG. 12, the open circuit voltage during light irradiation (open circuit voltage
voltago, Voc) and short circuit current
current Ish) is small. Next, when this element is heat treated in air at 230℃ for 20 minutes, the voltage -
The current characteristics are greatly improved, and good solar cell characteristics as shown by curve b in FIG. 12 can be obtained.

実施例 ３ また、ｎ−ｉ−ｐ多層膜ヘテロ接合の太陽電池
に適用することも可能であつた。まず、ステンレ
ステイール基板上にあらかじめ、非晶質水素化シ
リコンよりなるn+導電層（200Å）、水素を含有
する非晶質シリコンゲルマニウム（ａ−Si0.80
Ge0.20：Ｈ）を主体とするｉ型導電層（4000Å）
および非晶質水素化シリコンよりなるｐ型導電層
（250Å）を形成し、さらに、その上部に実施例１
と同様の方法で非晶質水素化シリコンよりなる
n+−ｉ−ｐ構造（だたしｉ層の膜厚は800Å）の
ホトダイオードを形成した後、実施例と同様の方
法で透明電極形成および熱処理を行うと性能の良
い太陽電池が得られた。Example 3 It was also possible to apply the present invention to an nip multilayer heterojunction solar cell. First, an n + conductive layer (200 Å) made of amorphous silicon hydride, an amorphous silicon germanium containing hydrogen (a-Si 0.80
I-type conductive layer (4000Å) mainly composed of Ge 0.20 :H)
and a p-type conductive layer (250 Å) made of amorphous hydrogenated silicon, and further on top of that a p-type conductive layer (250 Å) was formed.
made of amorphous hydrogenated silicon in the same manner as
After forming a photodiode with an n + -i-p structure (the thickness of the i layer was 800 Å), a solar cell with good performance was obtained by forming transparent electrodes and performing heat treatment in the same manner as in the example. .

以上の実施例を用いて説明した如く本発明の低
電圧駆動一次元光センサの構造方法を用いれば、
非晶質水素化シリコンよりなるホトダイオードの
上部にスパツタリング法で透明電極を堆積したこ
とにより発生したホトダイオードの光応答特性の
劣化を改善することができ、一次元の画像情報を
高速に読み取ることが可能な一次元センサあるい
は高効率の太陽電池を得ることができる。 As explained using the above embodiments, if the structure method of the low voltage drive one-dimensional optical sensor of the present invention is used,
It is possible to improve the deterioration of the photoresponse characteristics of the photodiode caused by depositing a transparent electrode by sputtering on the top of the photodiode made of amorphous hydrogenated silicon, making it possible to read one-dimensional image information at high speed. A one-dimensional sensor or a highly efficient solar cell can be obtained.

また、透明電極として前述した各種半透明金属
を用いても同様の効果を得ることができる。 Further, similar effects can be obtained by using the various semitransparent metals described above as the transparent electrode.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明の一次元光センサの原理的な構
造を示した断面図ａおよび平面図ｂ。第２図は本
発明の一般的な受光素子の断面図。第３図はスパ
ツタリング法で透明電極を形成した時の受光素子
の光反応特性の一例を示した図。第４図は本発明
の熱処理方法で改善した効果を光応答特性の一列
で示した図。第５図は熱処理前ａ後での光OFF
後の光電流の減衰特性を比較した図。第６図は本
発明の効果を熱処理効果を熱処理温度と3ms後の
残像との関係で示した図。第７図より第１１図は
各々本発明の一次元光センサの製造工程を示す主
要部断面図。第１２図は本発明の構造方法を太陽
電池に適用した場合の改善例を示した図である。 １……基板、２……非透光性金属電極、２１…
…ホトダイオードおよび分離ダイオード用金属電
極、２２……二層配線用金属電極、３……非晶質
水素化シリコンを主体とするホトダイオード、４
……非晶質水素化シリコンを主体とする分離ダイ
オード、３１，４１……非晶質水素化シリコンを
主体とするn+型導電層、３２，４２……非晶質
水素化シリコンを主体とするｎ型もしくはｉ型導
電層、３３，４３……非晶質水素化シリコンを主
体とするｐ型導電層、５……絶縁層、６１，６
２，６３，６４……コンタクト穴、７，１４……
透明電極もしくは半透明金属電極、８１，８２…
…金属配線、１０……入射光、１１……基板、１
２……下部電極、１３……非晶質水素化シリコン
を主体とするホトダイオード、１３１……非晶質
水素化シリコンを主体とするn+型導電層、１３
２……非晶質水素化シリコンを主体とするｎ型も
しくはｉ型導電層、１３３……非晶質水素化シリ
コンを主体とするｐ型導電層、１４……透明電極
もしくは半透明金属電極、１５……光パルス、１
６……電流計。 FIG. 1 is a sectional view a and a plan view b showing the basic structure of a one-dimensional optical sensor of the present invention. FIG. 2 is a sectional view of a general light receiving element of the present invention. FIG. 3 is a diagram showing an example of the photoreaction characteristics of a light-receiving element when a transparent electrode is formed by a sputtering method. FIG. 4 is a diagram showing the effects improved by the heat treatment method of the present invention in a row of photoresponse characteristics. Figure 5 shows the light turned off before and after heat treatment.
A diagram comparing the attenuation characteristics of the subsequent photocurrent. FIG. 6 is a diagram showing the heat treatment effect of the present invention in terms of the relationship between heat treatment temperature and afterimage after 3 ms. 7 to 11 are sectional views of main parts showing the manufacturing process of the one-dimensional optical sensor of the present invention, respectively. FIG. 12 is a diagram showing an example of improvement when the structural method of the present invention is applied to a solar cell. 1...Substrate, 2...Non-transparent metal electrode, 21...
... Metal electrode for photodiode and separation diode, 22 ... Metal electrode for double-layer wiring, 3 ... Photodiode mainly made of amorphous hydrogenated silicon, 4
...Separation diode mainly made of amorphous hydrogenated silicon, 31, 41...n + type conductive layer mainly made of amorphous hydrogenated silicon, 32, 42... Mainly made of amorphous hydrogenated silicon n-type or i-type conductive layer, 33, 43...p-type conductive layer mainly composed of amorphous hydrogenated silicon, 5... insulating layer, 61, 6
2, 63, 64... Contact hole, 7, 14...
Transparent electrode or translucent metal electrode, 81, 82...
...metal wiring, 10...incident light, 11...substrate, 1
2... Lower electrode, 13... Photodiode mainly made of amorphous hydrogenated silicon, 131... N + type conductive layer mainly made of amorphous hydrogenated silicon, 13
2... N-type or i-type conductive layer mainly composed of amorphous hydrogenated silicon, 133... P-type conductive layer mainly composed of amorphous hydrogenated silicon, 14... Transparent electrode or semi-transparent metal electrode, 15...Light pulse, 1
6...Ammeter.

Claims (1)

【特許請求の範囲】 １ 所望の基体上にシリコンを主体とした水素を
含有する非晶質材料より成る光導電膜を形成する
工程と、該光導電膜上にスパツタリング法によつ
て透明導電性膜を形成する工程を有する受光素子
の製造方法において、前記光導電膜はn+型導電
層、ｉもしくはｎ型導電層、ｐ型導電層の順に積
層され、前記透明導電性膜を形成した後、該受光
素子を170℃から250℃の温度範囲で15分以上加熱
する工程を有することを特徴とする受光素子の製
造方法。 ２ 上記基板が一次元に配列された非透光性金属
電極を少なくとも有し、該金属電極上に一対一に
対応するように上記光導電膜および上記透明電極
を形成後一次元の画像信号が取り出せるように配
線がなされた絶縁性基板であることを特徴とする
特許請求の範囲第１項記載の受光素子の構造方
法。 ３ 上記基板が二次元状に配列したスイツチと該
スイツチを介して取りだして光学像に相当する光
電荷を転送する走査素子を少なくとも有する半導
体基板であることを特徴とする特許請求の範囲第
１項記載の受光素子の製造方法。 ４ 上記透明導電性膜がスパツタリング法により
形成した酸化インジウム、酸化錫およびそれらの
混合物から選ばれた一つを主成分とする透明導電
性膜であることを特徴とする特許請求の範囲第１
項又は第２項記載の受光素子の製造方法。 ５ 上記透明導電性膜がスパツタリング法により
形成した金、白金、タンタル、モリブデン、アル
ミニウム、クロム、ニツケルおよびそれらの混合
物からなる群から選ばれた一つを主成分とする半
透明状の金属膜であることを特徴とする特許請求
の範囲第１項又は第２項記載の受光素子の製造方
法。 ６ 上記加熱の時間は20分から60分の範囲である
ことを特徴とする特許請求の範囲第１項ないし第
５項の何れかに記載の受光素子の製造方法。[Claims] 1. A step of forming a photoconductive film made of an amorphous material containing silicon and hydrogen on a desired substrate, and forming a transparent conductive film on the photoconductive film by a sputtering method. In the method for manufacturing a light-receiving element, which includes a step of forming a film, the photoconductive film is laminated in the order of an n + type conductive layer, an i or n type conductive layer, and a p type conductive layer, and after forming the transparent conductive film. A method for manufacturing a light receiving element, comprising the step of heating the light receiving element at a temperature in the range of 170°C to 250°C for 15 minutes or more. 2. The substrate has at least non-transparent metal electrodes arranged in one dimension, and after forming the photoconductive film and the transparent electrode in one-to-one correspondence on the metal electrodes, a one-dimensional image signal is generated. 2. The method of constructing a light receiving element according to claim 1, wherein the light receiving element is an insulating substrate with wiring so that it can be taken out. 3. Claim 1, wherein the substrate is a semiconductor substrate having at least two-dimensionally arranged switches and a scanning element for transferring photoelectric charges corresponding to an optical image taken out through the switches. A method of manufacturing the light-receiving element described above. 4. Claim 1, wherein the transparent conductive film is a transparent conductive film formed by a sputtering method and whose main component is one selected from indium oxide, tin oxide, and a mixture thereof.
2. A method for manufacturing a light-receiving element according to item 1 or 2. 5 The transparent conductive film is a translucent metal film formed by a sputtering method and whose main component is one selected from the group consisting of gold, platinum, tantalum, molybdenum, aluminum, chromium, nickel, and mixtures thereof. A method for manufacturing a light-receiving element according to claim 1 or 2, characterized in that: 6. The method for manufacturing a light receiving element according to any one of claims 1 to 5, wherein the heating time is in a range of 20 minutes to 60 minutes.
JP56167208A 1981-03-13 1981-10-21 Manufacture of light-receiving element Granted JPS5868965A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
JP56167208A JPS5868965A (en) 1981-10-21 1981-10-21 Manufacture of light-receiving element
US06/357,076 US4412900A (en) 1981-03-13 1982-03-11 Method of manufacturing photosensors
DE8282301284T DE3276889D1 (en) 1981-03-13 1982-03-12 Method of manufacturing photosensors
EP82301284A EP0060699B1 (en) 1981-03-13 1982-03-12 Method of manufacturing photosensors
CA000398275A CA1168739A (en) 1981-03-13 1982-03-12 Method of manufacturing photosensors
KR8201078A KR860000160B1 (en) 1981-03-13 1982-03-13 Method of manufacturing photosensors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56167208A JPS5868965A (en) 1981-10-21 1981-10-21 Manufacture of light-receiving element

Publications (2)

Publication Number Publication Date
JPS5868965A JPS5868965A (en) 1983-04-25
JPH0451983B2 true JPH0451983B2 (en) 1992-08-20

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP56167208A Granted JPS5868965A (en) 1981-03-13 1981-10-21 Manufacture of light-receiving element

Country Status (1)

Country Link
JP (1) JPS5868965A (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5162644A (en) * 1988-03-14 1992-11-10 Hitachi, Ltd. Contact type image sensor having photoelectric conversion elements to reduce signal variation caused by luminous intensity variation of light source
JPH02140853U (en) * 1989-04-26 1990-11-26

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5342693A (en) * 1976-09-29 1978-04-18 Rca Corp Semiconductor device including amorphous silicone layer
JPH0214790A (en) * 1988-05-06 1990-01-18 Steamatic Inc Cleaner for air duct

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5342693A (en) * 1976-09-29 1978-04-18 Rca Corp Semiconductor device including amorphous silicone layer
JPH0214790A (en) * 1988-05-06 1990-01-18 Steamatic Inc Cleaner for air duct

Also Published As

Publication number Publication date
JPS5868965A (en) 1983-04-25

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