JPH0876140A - Spacial optical modulating element and its production - Google Patents
Spacial optical modulating element and its productionInfo
- Publication number
- JPH0876140A JPH0876140A JP3688695A JP3688695A JPH0876140A JP H0876140 A JPH0876140 A JP H0876140A JP 3688695 A JP3688695 A JP 3688695A JP 3688695 A JP3688695 A JP 3688695A JP H0876140 A JPH0876140 A JP H0876140A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- light
- light modulator
- dielectric mirror
- spatial light
- 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.)
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Links
Landscapes
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Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、フラットパネルディス
プレイ、光演算素子、ビデオプロジェクタ等に組み込ま
れる空間光変調素子(SLM)とその製造方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spatial light modulator (SLM) incorporated in a flat panel display, an optical operation element, a video projector, etc., and a manufacturing method thereof.
【0002】[0002]
【従来の技術】ディスプレイやプロジェクタ等に組み込
まれる空間光変調素子は、アモルファスシリコン等から
なる光導電体層に書き込み光を入射せしめ、光導電体層
の導電性を書き込み光の強度に応じて変化せしめ、この
変化によって生じた導電性の分布が電源からの電圧によ
って光変調体(液晶)に印加される。一方、光変調体に
読み出し光を入射すると、光変調体には書き込み光の強
度分布に応じた電界が影響しているので入射光は光変調
され、誘電体ミラー層にて反射されて出力される構造に
なっている。2. Description of the Related Art A spatial light modulator incorporated in a display, a projector, or the like makes writing light incident on a photoconductive layer made of amorphous silicon or the like, and changes the conductivity of the photoconductive layer according to the intensity of the writing light. At the very least, the conductivity distribution generated by this change is applied to the light modulator (liquid crystal) by the voltage from the power source. On the other hand, when the reading light is incident on the light modulator, the incident light is optically modulated, reflected by the dielectric mirror layer, and output because the electric field according to the intensity distribution of the writing light influences the light modulator. It has a structure that
【0003】ところで、読み出し光は書き込み光に比べ
て大幅に強度が強く、誘電体ミラー層だけでは読み出し
光が光導電体層まで到達するのを完全に防ぐことができ
ず、読み出し光が光導電体層まで到達して電荷の乱れを
生じる不利がある。そこで、公表特許平2−50133
4号公報に開示されるように、誘電体ミラー層の内側
(光導電体層側)にCdTe遮光層を設けることが知られ
ている。その他、遮光層材料としてSiO2中に多量のニ
ッケル(Ni )や亜鉛(Zn )を含ませたサーメットが
用いられてきた。By the way, the read light is much stronger than the write light, and the dielectric mirror layer alone cannot completely prevent the read light from reaching the photoconductor layer, and the read light is photoconductive. It has the disadvantage of reaching the body layer and causing charge disturbance. Therefore, published Japanese Patent Application No. 2-50133
It is known to provide a CdTe light-shielding layer inside the dielectric mirror layer (on the side of the photoconductor layer) as disclosed in Japanese Patent Laid-Open No. 4 (1994). In addition, a cermet in which a large amount of nickel (Ni) or zinc (Zn) is contained in SiO 2 has been used as a light shielding layer material.
【0004】[0004]
【発明が解決しようとする課題】しかしながら、CdTe
遮光層を設けることで読み出し光の光導電体層への到達
を防止できるが、CdTe遮光層の抵抗率は106〜108
Ω・cmであり、十分な抵抗率と言えず、製造条件によ
っては102 Ω・cmとなる場合もある。このため、C
dTe遮光層と接合層との界面に電荷が発生してその電荷
が広がり、即ち光導電体層の導電率変化を損失なく液晶
に伝えることができず、その結果液晶(光変調体)の配
向領域が広がり、画像の解像度が低下する。また、前記
サーメットは抵抗率が低く、遮光特性(読み出し光の光
導電体層への到達を防止する能力)も不十分であった。[Problems to be Solved by the Invention] However, CdTe
By providing the light shielding layer, it is possible to prevent the readout light from reaching the photoconductor layer, but the resistivity of the CdTe light shielding layer is 10 6 to 10 8
Ω · cm, which cannot be said to be sufficient resistivity, and may be 10 2 Ω · cm depending on manufacturing conditions. Therefore, C
A charge is generated at the interface between the dTe light-shielding layer and the bonding layer, and the charge spreads, that is, the change in the conductivity of the photoconductor layer cannot be transmitted to the liquid crystal without loss, and as a result, the alignment of the liquid crystal (light modulator). The area is expanded and the resolution of the image is reduced. Further, the cermet has a low resistivity, and the light-shielding property (the ability to prevent the readout light from reaching the photoconductor layer) was insufficient.
【0005】[0005]
【課題を解決するための手段】上記課題を解決すべく本
発明の空間光変調素子は、光書き込み手段によって光導
電体層に情報を書き込み、この書き込んだ情報に応じて
光変調体を変調させ、この光変調体に入射した読み出し
光を誘電体ミラー層によって反射せしめるようにした空
間光変調素子において、前記光導電体層と誘電体ミラー
層との間にCdTe(テルル化カドミウム)にI族元素
(H,Li,Na,K,Cu,Rb,Ag,Cs,Au,Fr)
を不純物として添加した遮光層を設けた。ここで、I族
元素の添加量は1〜1,000ppm、好ましくは30
0〜400ppmとする。In order to solve the above problems, a spatial light modulator of the present invention writes information in a photoconductor layer by an optical writing means and modulates the light modulator according to the written information. In a spatial light modulator in which the reading light incident on the light modulator is reflected by a dielectric mirror layer, CdTe (cadmium telluride) group I is added between the photoconductor layer and the dielectric mirror layer. Element (H, Li, Na, K, Cu, Rb, Ag, Cs, Au, Fr)
A light-shielding layer to which was added as an impurity was provided. Here, the addition amount of the group I element is 1 to 1,000 ppm, preferably 30
It is set to 0 to 400 ppm.
【0006】また、前記光導電体層をアモルファスシリ
コン層とし、この光導電体層と遮光層との間に、順にS
iO2層、CdTeにI族元素が添加されたO2 リッチな層
及びCdTeにI族元素が添加された層を積層してなる接
合層を設け、或いは前記誘電体ミラー層をTiO2とSi
O2とを交互に積層して構成し、この誘電体ミラー層と
前記遮光層との間に、SiO2層、CdTeにI族元素が添
加されたO2 リッチな層及びCdTeにI族元素が添加さ
れた層を積層してなる接合層を設けることで、光導電体
層と遮光層との接合強度及び遮光層と誘電体ミラー層と
の接合強度を高めるようにしてもよい。Further, the photoconductor layer is an amorphous silicon layer, and S is sequentially provided between the photoconductor layer and the light shielding layer.
A bonding layer formed by laminating an iO 2 layer, an O 2 -rich layer in which a group I element is added to CdTe, and a layer in which a group I element is added to CdTe is provided, or the dielectric mirror layer is formed of TiO 2 and Si.
O 2 is alternately laminated, and a SiO 2 layer, an O 2 -rich layer in which a group I element is added to CdTe, and a group I element in CdTe are provided between the dielectric mirror layer and the light shielding layer. It is also possible to increase the bonding strength between the photoconductor layer and the light-shielding layer and the bonding strength between the light-shielding layer and the dielectric mirror layer by providing a bonding layer formed by stacking layers to which is added.
【0007】また、本発明の空間光変調素子は、光書き
込み手段によって光導電体層に情報を書き込み、この書
き込んだ情報に応じて光変調体を変調させ、この光変調
体に入射した読み出し光を誘電体ミラー層によって反射
せしめるようにした空間光変調素子において、前記光導
電体層と誘電体ミラー層との間にCdTe(テルル化カド
ミウム)にV族元素(N,P,As,Sb,Bi )を不純
物として添加した遮光層を設けた。Further, in the spatial light modulator of the present invention, information is written in the photoconductor layer by the optical writing means, the light modulator is modulated according to the written information, and the read light incident on the light modulator is read. In the spatial light modulator in which the dielectric mirror layer is used to reflect the light, a group V element (N, P, As, Sb, CdTe (cadmium telluride)) is provided between the photoconductive layer and the dielectric mirror layer. A light-shielding layer doped with Bi) was provided.
【0008】一方、本発明に係る空間光変調素子の製造
方法は、透明電極及び光導電体層がこの順に形成された
基板上に高周波スパッタ法によって順次、接合層、遮光
層、接合層を形成して、この接合層上に誘電体ミラー層
を形成し、この誘電体ミラー層と他の基板表面に形成し
た透明電極との間に光変調体を注入するようにした空間
光変調素子の製造方法において、前記高周波スパッタ法
は基板温度を120℃〜200℃に維持して行い、且つ
遮光層生成のためのスパッタ時間は2時間以上とした。
また、前記基板に誘電体ミラー層を形成した後、基板温
度を120℃〜200℃に維持した状態で、30分〜2
時間アニール処理を行うことが安定した品質の空間光変
調素子を得る上で好ましい。On the other hand, in the method for manufacturing a spatial light modulator according to the present invention, a bonding layer, a light shielding layer, and a bonding layer are sequentially formed by a high frequency sputtering method on a substrate on which a transparent electrode and a photoconductor layer are formed. Then, a dielectric mirror layer is formed on the bonding layer, and a light modulator is injected between the dielectric mirror layer and a transparent electrode formed on the surface of another substrate to manufacture a spatial light modulator. In the method, the high frequency sputtering method was performed while maintaining the substrate temperature at 120 to 200 ° C., and the sputtering time for forming the light shielding layer was set to 2 hours or more.
Further, after forming the dielectric mirror layer on the substrate, the substrate temperature is maintained at 120 ° C to 200 ° C for 30 minutes to 2 minutes.
It is preferable to perform the time annealing treatment in order to obtain a spatial light modulator having stable quality.
【0009】また、本発明の空間光変調素子の製造方法
は、透明電極及び光導電体層がこの順に形成された基板
上に高周波スパッタ法によって遮光層を形成して、この
遮光層上に誘電体ミラー層を形成し、この誘電体ミラー
層と他の基板表面に形成した透明電極との間に光変調体
を注入するようにした空間光変調素子の製造方法におい
て、前記遮光層は、基板温度を0〜100℃とし、放電
ガス圧を10〜100mTorr として形成した。Further, in the method for manufacturing a spatial light modulator of the present invention, a light shielding layer is formed by a high frequency sputtering method on a substrate on which a transparent electrode and a photoconductor layer are formed in this order, and a dielectric layer is formed on the light shielding layer. In the method for manufacturing a spatial light modulator in which a body mirror layer is formed and a light modulator is injected between the dielectric mirror layer and a transparent electrode formed on the surface of another substrate, the light shielding layer is a substrate. The temperature was set to 0 to 100 ° C., and the discharge gas pressure was set to 10 to 100 mTorr.
【0010】[0010]
【作用】スパッタリングによって形成されるCdTe膜
(遮光層)の元素の比は、各元素の蒸気圧の違い及び下
地膜(接合層)に対する付着確率の違いにより、化学量
論的組成(1:1)にはならず格子欠陥を有する。この
ため、ドナーやアクセプタの比率が変動し、どちらか多
い方の伝導型になり、自由なキャリヤ濃度も変動するの
で抵抗率にバラツキが生じる。そこで、CdTe(II−VI
族)半導体に対してアクセプタとなるI族元素またはV
族元素を注入してキャリヤをバンドギャップ内の深い位
置に捕獲し、キャリヤを伝導帯に励起させないようにす
ることで、抵抗率を高いレベルで安定させることが可能
になった。The ratio of elements in the CdTe film (light-shielding layer) formed by sputtering is stoichiometric (1: 1) due to the difference in vapor pressure of each element and the difference in sticking probability to the underlying film (bonding layer). ) And has a lattice defect. As a result, the ratio of donors and acceptors changes, whichever is the larger conductivity type, and the free carrier concentration also changes, resulting in variations in resistivity. Therefore, CdTe (II-VI
Group I element or V that serves as an acceptor for semiconductors
By implanting a group element and trapping the carriers at a deep position in the band gap so as not to excite the carriers into the conduction band, it becomes possible to stabilize the resistivity at a high level.
【0011】[0011]
【実施例】以下に本発明の実施例を添付図面に基づいて
説明する。ここで、図1は本発明に係る空間光変調素子
を組み込んだプロジェクタの全体構成図であり、LED
を直線状に配列した発光素子アレイ1から放射された書
き込み光F1はレンズ2で平行光とされ、反射角調整可
能な偏向ミラー3及びレンズ4を介して本発明に係る空
間光変調素子10の光導電層に結像し、空間光変調素子
10内の光変調体である液晶を書き込み情報に応じて配
向させる。Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is an overall configuration diagram of a projector in which the spatial light modulator according to the present invention is incorporated.
The writing light F1 emitted from the light emitting element array 1 in which is linearly arranged is collimated by the lens 2 and is transmitted through the deflecting mirror 3 and the lens 4 whose reflection angle can be adjusted to the spatial light modulating element 10 of the present invention. An image is formed on the photoconductive layer, and the liquid crystal that is the light modulator in the spatial light modulator 10 is oriented according to the write information.
【0012】また、読み出し光F2は球面反射鏡5、偏
光ビームスプリッタ6を介して空間光変調素子10に入
射して変調され、空間光変調素子10の誘電体ミラー層
で反射し、反射光F3がレンズ8を介してスクリーン9
に投影される。The reading light F2 is incident on the spatial light modulator 10 through the spherical reflecting mirror 5 and the polarization beam splitter 6 and is modulated, reflected by the dielectric mirror layer of the spatial light modulator 10, and reflected light F3. Through the lens 8 to the screen 9
Projected on.
【0013】空間光変調素子10は全体斜視図である図
2に示すように、ガラス基板11の一面にITO(イン
ジウム・スズ・オキサイド)からなる透明電極12を形
成し、この透明電極12上にアモルファスシリコンから
なる光導電体層13を形成し、この光導電体層13の上
に接合層14を介してCdTe(テルル化カドミウム)に
I族元素(H,Li,Na,K,Cu,Rb,Ag,Cs,A
u,Fr)を不純物として添加した遮光層15を形成し、
この遮光層15の上に接合層16を介して誘電体ミラー
層17を形成している。As shown in FIG. 2 which is an overall perspective view of the spatial light modulation element 10, a transparent electrode 12 made of ITO (indium tin oxide) is formed on one surface of a glass substrate 11, and the transparent electrode 12 is formed on the transparent electrode 12. A photoconductor layer 13 made of amorphous silicon is formed, and a group I element (H, Li, Na, K, Cu, Rb) is added to CdTe (cadmium telluride) via a bonding layer 14 on the photoconductor layer 13. , Ag, Cs, A
u, Fr) is added as an impurity to form a light-shielding layer 15,
A dielectric mirror layer 17 is formed on the light shielding layer 15 with a bonding layer 16 interposed therebetween.
【0014】そして、誘電体ミラー層17と他のガラス
基板21の一面に形成した透明電極22との間に液晶
(光変調体)23を介設し、更に透明電極12,22間
に電源24を接続することで空間光変調素子10が完成
する。A liquid crystal (light modulator) 23 is provided between the dielectric mirror layer 17 and the transparent electrode 22 formed on one surface of another glass substrate 21, and a power source 24 is provided between the transparent electrodes 12 and 22. The spatial light modulator 10 is completed by connecting the above.
【0015】前記接合層14は要部の拡大断面図である
図3に示すように、光導電体層13から遮光層15に向
かって順にSiO2層14a、CdTeにCu が添加された
O2リッチなCdTe+Cu層14b及びCdTeにCu が添
加されたCdTe+Cu層14cを積層して構成される。こ
こで、CdTe+Cu層14b及びCdTe+Cu層14cにお
けるCu の添加量は遮光層15と同様に1〜1,000
ppm、好ましくは300〜400ppmとする。As shown in FIG. 3, which is an enlarged cross-sectional view of the main portion of the bonding layer 14, an SiO 2 layer 14a and an O 2 layer in which Cu is added to CdTe are sequentially provided from the photoconductor layer 13 toward the light shielding layer 15. It is configured by laminating a rich CdTe + Cu layer 14b and a CdTe + Cu layer 14c in which Cu is added to CdTe. Here, the addition amount of Cu in the CdTe + Cu layer 14b and the CdTe + Cu layer 14c is 1 to 1,000 as in the light shielding layer 15.
ppm, preferably 300 to 400 ppm.
【0016】また、接合層16は前記接合層14とは順
序を逆にし、遮光層15から誘電体ミラー層17に向か
って順にCdTeにCu が添加されたCdTe+Cu層16
a、CdTeにCu が添加されたO2 リッチなCdTe+Cu
層16b及びSiO2層16cを積層して構成される。
尚、誘電体ミラー層17と液晶23との間には配向層2
5aを形成している。Further, the order of the bonding layer 16 is reversed from that of the bonding layer 14, and the CdTe + Cu layer 16 in which Cu is added to CdTe in order from the light shielding layer 15 to the dielectric mirror layer 17 is formed.
a, O 2 -rich CdTe + Cu in which Cu is added to CdTe
The layer 16b and the SiO 2 layer 16c are laminated.
The alignment layer 2 is provided between the dielectric mirror layer 17 and the liquid crystal 23.
5a is formed.
【0017】次に、サンプル1〜5について具体的な製
造方法を述べる。 (サンプル1)一面側にアモルファスシリコン層をすで
に形成したガラス基板(コーニング社7059)を高周
波マグネトロンスパッタ装置内に設置する。この高周波
マグネトロンスパッタ装置内の適当な箇所には、6N
(6ナイン)以上の純度のCdTeターゲットと3N以上
の純度のCu ターゲットがセットされ、更に13.56
MHz の高周波が印加される。先ず、基板温度を150
℃に保持したまま真空度を2×10-6Torr以下とし、バ
リアブルコンダクタンスバルブを全開状態でAr ガスを
3mTorr (ミリトール)導入し、SiO2を300W(ワッ
ト)で7分間成長せしめる。次いで、Ar ガスを維持し
たまま、6N以上の純度のO2 ガスを3mTorr 加え、バ
リアブルコンダクタンスバルブを絞って全ガス圧力が、
例えば9mTorr となるようにしてO2 リッチなCdTe+
Cu層を5分間成長せしめる。更に、バリアブルコンダ
クタンスバルブを開けながら、全ガス圧力を9mTorrに
維持してO2 の導入量を少しずつ減らして止め、CdTe
+Cu層を5分間成長せしめる。この後、バリアブルコン
ダクタンスバルブを全開しAr ガスを3mTorr として、
2時間以上かけてCdTe+Cu遮光層を1.5μm成長せ
しめた。このようにして得られたものをサンプル1とす
る。Next, a concrete manufacturing method for Samples 1 to 5 will be described. (Sample 1) A glass substrate (Corning 7059) having an amorphous silicon layer already formed on one surface side is placed in a high frequency magnetron sputtering apparatus. At a suitable place in this high frequency magnetron sputtering device, 6N
A CdTe target having a purity of (6 nines) or higher and a Cu target having a purity of 3N or higher are set, and 13.56
A high frequency of MHz is applied. First, the substrate temperature is set to 150
While maintaining the temperature at 0 ° C., the degree of vacuum is set to 2 × 10 −6 Torr or less, Ar gas is introduced at 3 mTorr (millitorr) with the variable conductance valve fully opened, and SiO 2 is grown at 300 W (watt) for 7 minutes. Next, while maintaining the Ar gas, O 2 gas having a purity of 6N or more was added at 3 mTorr, and the variable conductance valve was throttled to adjust the total gas pressure to
For example, CdTe + rich in O 2 at 9 mTorr
Allow the Cu layer to grow for 5 minutes. Furthermore, while opening the variable conductance valve, the total gas pressure was maintained at 9 mTorr and the amount of O 2 introduced was gradually reduced to CdTe.
Allow + Cu layer to grow for 5 minutes. After that, the variable conductance valve was fully opened and Ar gas was set to 3 mTorr.
The CdTe + Cu light-shielding layer was grown to a thickness of 1.5 μm over 2 hours. The sample thus obtained is referred to as Sample 1.
【0018】(サンプル2)上記のサンプル1を作るま
での工程は同じであるが、更に引続いて、バリアブルコ
ンダクタンスバルブを絞り、Ar ガス圧力を9mTorr と
してCdTe+Cu層を成長せしめる。次いで、O2 の導入
量を少しづつ増加するとともに全ガス圧力を9mTorr に
維持するためバリアブルコンダクタンスバルブを同時に
少しづつ開く。そして、O2 の流量がサンプル1で形成
したO2 リッチなCdTe+Cu層を形成した時と同じにな
ったらこの操作を止め、CdTe+Cu層を5分間成長せし
める。このようにして得られたものをサンプル2とす
る。(Sample 2) The steps up to the preparation of Sample 1 are the same, but the variable conductance valve is further narrowed down and the CdTe + Cu layer is grown with the Ar gas pressure set to 9 mTorr. Then, the variable conductance valve is simultaneously opened little by little in order to gradually increase the amount of O 2 introduced and maintain the total gas pressure at 9 mTorr. Then, the flow rate of O 2 is stop this operation If the same in a case of forming the O 2 rich CdTe + Cu layer formed in Sample 1, allowed to grow CdTe + Cu layer 5 minutes. The sample thus obtained is referred to as Sample 2.
【0019】(サンプル3)サンプル2を作製した後、
真空を破らずに、基板温度を150℃に維持したまま全
てのスパッタリングを止め、そのままチャンバー内に
1.5時間放置(アニール)してから取り出す。このよ
うにして得られたものをサンプル3とする。(Sample 3) After producing Sample 2,
Without breaking the vacuum, all the sputtering was stopped while maintaining the substrate temperature at 150 ° C., and the substrate was left as it was in the chamber for 1.5 hours (annealing) before taking it out. The sample thus obtained is referred to as Sample 3.
【0020】(サンプル4)接合層としてのSiO2層、
O2 リッチなCdTe+Cu層及びCdTe+Cu層を形成しな
いで、アモルファスシリコン層上に直接遮光層(CdTe
+Cu)を形成し、これをサンプル4とする。(Sample 4) SiO 2 layer as a bonding layer,
Without forming the O 2 -rich CdTe + Cu layer and the CdTe + Cu layer, the light-shielding layer (CdTe) is directly formed on the amorphous silicon layer.
+ Cu) is formed, and this is referred to as Sample 4.
【0021】(サンプル5)公表特許平2−50133
4号公報に開示されたもの、つまり接合層(Cu の添加
なし)はあるが、遮光層をCdTe(Cu の添加なし)と
したものをサンプル5とする。(Sample 5) Published Japanese Patent Application No. 2-50133
Sample 5 is the one disclosed in Japanese Patent Laid-Open No. 4, that is, the bonding layer (without addition of Cu) is present, but the light-shielding layer is CdTe (without addition of Cu).
【0022】以上のサンプル1〜5の明暗抵抗率を以下
の(表1)に示す。尚、各サンプルの抵抗率を計るため
に必要な電極についてはAl 電極を形成した。またサン
プル1〜3についての光学濃度(Optical Density:O.
D.)の値は700nmの波長で2であり、従来と変り
はなかった。なお、光学濃度とは透過率の逆数の自然対
数値である。The bright and dark resistivities of the above samples 1 to 5 are shown in the following (Table 1). An Al electrode was formed as an electrode necessary for measuring the resistivity of each sample. Further, the optical densities (O.D.
D. The value of () is 2 at a wavelength of 700 nm, which is no different from the conventional value. The optical density is the natural logarithm of the reciprocal of the transmittance.
【0023】[0023]
【表1】 [Table 1]
【0024】上記の(表1)から以下のことが言える。 サンプル2からCu が添加されてもアニール処理がな
されないものは、抵抗率が低い。サンプル1にあっては
遮光層を形成する際に、基板温度を150℃としつつ2
時間以上としたことによってアニール処理したと同様の
効果が得られ、抵抗率が向上したものと考えられる。 サンプル4と5の比較から、Cu を添加することによ
って抵抗率は向上する。 Cu が添加され且つ接合層を設け更にアニールが施さ
れたサンプル1,3は従来の素子に比べて、大幅に抵抗
率が向上し、更に明・暗抵抗率の差がなくなる。From the above (Table 1), the following can be said. Sample 2 which is not annealed even if Cu is added has a low resistivity. In Sample 1, when forming the light shielding layer, the substrate temperature was set to 150 ° C.
It is considered that the same effect as the annealing treatment was obtained by setting the time longer than the time, and the resistivity was improved. From the comparison of Samples 4 and 5, the resistivity is improved by adding Cu. Samples 1 and 3 to which Cu was added and which was provided with a bonding layer and further annealed had a significantly improved resistivity as compared with the conventional device, and there was no difference between the bright and dark resistivity.
【0025】Cu 以外の他のI族金属であるAg,Auに
ついてもサンプルを作製したが、同様の結果が得られ
た。Samples were also prepared for Ag and Au which are other Group I metals other than Cu, but similar results were obtained.
【0026】H2 については、Ar 中に10〜50%と
なるようにH2 を混入し、Cu 等の金属ターゲットをセ
ットせず、全ガス圧が6.0×10-3Torrとなるように
導入し、上記と同一の条件でスパッタリングを行い、1
08 Ω・cm台の抵抗値が得られた。Regarding H 2 , H 2 is mixed in Ar so as to be 10 to 50%, a metal target such as Cu is not set, and the total gas pressure is 6.0 × 10 -3 Torr. And sputter under the same conditions as above.
0 8 Ω · cm base resistance value is obtained.
【0027】次に、本発明の別実施例を図4に基づいて
説明する。図4は本発明に係る別の空間光変調素子の斜
視図であり、空間光変調素子30は、透明基板31の一
面にITOからなる透明電極32を形成し、この透明電
極32上にアモルファス水素化シリコンからなる光導電
体層33を形成し、この光導電体層33の上にCdTe
(テルル化カドミウム)にV族元素(N,P,As,S
b,Bi )を不純物として添加した遮光層34を形成
し、この遮光層34の上に誘電体ミラー層35を形成し
ている。Next, another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a perspective view of another spatial light modulator according to the present invention. In the spatial light modulator 30, a transparent electrode 32 made of ITO is formed on one surface of a transparent substrate 31, and amorphous hydrogen is formed on the transparent electrode 32. A photoconductor layer 33 made of silicon oxide is formed, and CdTe is formed on the photoconductor layer 33.
(Cadmium telluride) with group V elements (N, P, As, S)
b, Bi) is added as an impurity to form a light shielding layer 34, and a dielectric mirror layer 35 is formed on the light shielding layer 34.
【0028】そして、誘電体ミラー層35と他の透明基
板36の一面に形成した透明電極37との間に液晶(光
変調体)38を介設し、更に透明電極32,37間に電
源41を接続することで空間光変調素子30が完成す
る。A liquid crystal (light modulator) 38 is provided between the dielectric mirror layer 35 and a transparent electrode 37 formed on one surface of another transparent substrate 36, and a power source 41 is provided between the transparent electrodes 32 and 37. The spatial light modulator 30 is completed by connecting the above.
【0029】以下に具体的な製造方法を述べる。一方の
透明基板31上にITOからなる透明電極32をスパッ
タリング法により形成する。この透明電極32上に、a
-Si:H(アモルファス水素化シリコン)からなる膜厚
が20μmの光導電体層33をCVD法により積層す
る。A specific manufacturing method will be described below. A transparent electrode 32 made of ITO is formed on one transparent substrate 31 by a sputtering method. On this transparent electrode 32, a
A photoconductor layer 33 made of Si: H (amorphous silicon hydride) and having a thickness of 20 μm is laminated by the CVD method.
【0030】そして、光導電体層33上に、遮光層34
を積層する。この遮光層34は窒素(N)を添加された
CdTeを、高周波マグネトロンスパッタリング法(高周
波スパッタ法の一種である。)により2.3μm積層し
たものである。スパッタリングガスにはアルゴン(Ar
)を用い、このアルゴンに対して窒素ガス(N2 )濃
度を2.2%として、成膜圧力(放電ガス圧)10mTor
r 、高周波電力0.6W/cm2 、基板温度を室温として
スパッタリングを行う。このようにして得られた遮光層
34の抵抗率は4×108Ω・cmであり、剥がれやひび割
れは認められなかった。Then, a light shielding layer 34 is formed on the photoconductor layer 33.
Are laminated. The light-shielding layer 34 is formed by laminating CdTe added with nitrogen (N) by 2.3 μm by a high frequency magnetron sputtering method (which is a kind of high frequency sputtering method). Argon (Ar
) Is used and the nitrogen gas (N 2 ) concentration is 2.2% with respect to this argon, and the film formation pressure (discharge gas pressure) is 10 mTor.
Sputtering is performed at r, high frequency power of 0.6 W / cm 2 , and substrate temperature of room temperature. The light-shielding layer 34 thus obtained had a resistivity of 4 × 10 8 Ω · cm, and no peeling or cracking was observed.
【0031】このように、前記遮光層は基板温度を10
0℃より低い室温とし、放電ガス圧を10mTorr とし
て、高周波スパッタ法により形成したので、遮光層34
の抵抗率が108Ω・cm以上となり、光導電体層33の導
電率変化を損失なく液晶38に伝えることができる。As described above, the light-shielding layer has a substrate temperature of 10
The light shielding layer 34 was formed by the high frequency sputtering method at a room temperature lower than 0 ° C. and a discharge gas pressure of 10 mTorr.
Has a resistivity of 10 8 Ω · cm or more, and the change in conductivity of the photoconductor layer 33 can be transmitted to the liquid crystal 38 without loss.
【0032】また、得られた遮光層34の光学濃度を図
5に示す。図5によれば、波長400〜800nmで光
学濃度の値は2.5〜7.5であり、十分な遮光性を有
することが確認できる。このように、遮光層34が抵抗
率が高く、遮光性も十分であるので、空間光変調素子の
画像品質を良好にすることができる。The optical density of the obtained light shielding layer 34 is shown in FIG. According to FIG. 5, the value of the optical density is 2.5 to 7.5 at a wavelength of 400 to 800 nm, and it can be confirmed that the optical density is sufficient. In this way, since the light-shielding layer 34 has a high resistivity and a sufficient light-shielding property, it is possible to improve the image quality of the spatial light modulator.
【0033】さらに、遮光層34上に誘電体ミラー層3
5を積層する。この誘電体ミラー層35はSiO2とTi
O2とをSi 及びTi をターゲットとして直流スパッタ
法を用いて交互に積層することにより形成する。誘電体
ミラー層35にも遮光層34と同様に剥がれやひび割れ
は認められなかった。Further, the dielectric mirror layer 3 is formed on the light shielding layer 34.
5 is laminated. This dielectric mirror layer 35 is made of SiO 2 and Ti.
O 2 and O 2 are formed by alternately stacking Si and Ti as targets using a DC sputtering method. As with the light shielding layer 34, neither peeling nor cracking was observed in the dielectric mirror layer 35.
【0034】さて、もう一方の透明基板36上にITO
からなる透明電極37をスパッタリング法により形成す
る。誘電体ミラー層35及び透明電極37の上にSiO2
からなる配向層39a及び39bをスパッタリング法に
よりそれぞれ形成する。この配向層39a及び39bは
液晶分子を配向させるためにある。Now, ITO is formed on the other transparent substrate 36.
The transparent electrode 37 made of is formed by the sputtering method. SiO 2 is formed on the dielectric mirror layer 35 and the transparent electrode 37.
Alignment layers 39a and 39b are formed by sputtering. The alignment layers 39a and 39b are for aligning liquid crystal molecules.
【0035】配向層39a及び39bが形成された透明
基板31及び36を、図示していないスペーサー及びシ
ール材を介して貼り合わせ、両基板31,36の間に液
晶38(光変調体)を挟持する。The transparent substrates 31 and 36 on which the alignment layers 39a and 39b are formed are pasted together via a spacer and a sealing material (not shown), and a liquid crystal 38 (light modulator) is sandwiched between the substrates 31 and 36. To do.
【0036】このように、本空間光変調素子は強い読み
出し光に対応して遮光特性の十分な遮光層を有してお
り、この遮光層により画像品質が極めて良好である。As described above, the present spatial light modulator has the light-shielding layer having a sufficient light-shielding property in response to the strong read light, and the light-shielding layer provides extremely good image quality.
【0037】N以外の他のV族元素であるP,As,S
b,Bi についてもサンプルを作製したが、同様の結果
が得られた。P, As, S which are other V group elements other than N
Samples were also prepared for b and Bi, but similar results were obtained.
【0038】[0038]
【発明の効果】本発明は上記構成により、次の効果を発
揮する。請求項1の空間光変調素子は、空間光変調素子
の光導電体層と誘電体ミラー層との間に設ける遮光層と
して、CdTe(テルル化カドミウム)にCu 等のI族元
素を不純物として添加したので、高抵抗で且つ抵抗値に
バラツキがなく、更に明・暗抵抗率の差が小さい遮光層
が得られる。The present invention has the following effects due to the above configuration. The spatial light modulation element according to claim 1 is used as a light-shielding layer provided between the photoconductor layer and the dielectric mirror layer of the spatial light modulation element, wherein CdTe (cadmium telluride) is doped with a Group I element such as Cu as an impurity. Therefore, it is possible to obtain a light-shielding layer having high resistance, no variation in resistance value, and a small difference in light / dark resistivity.
【0039】請求項2の空間光変調素子は、アモルファ
スシリコン層からなる光導電体層と遮光層との間に、S
iO2層、CdTeにI族元素が添加されたO2 リッチな層
及びCdTeにI族元素が添加された層を積層してなる接
合層を設けることで、光導電体層と遮光層との剥離を防
止することができる。In the spatial light modulator according to the second aspect of the present invention, an S element is provided between the photoconductor layer made of an amorphous silicon layer and the light shielding layer.
By providing a joining layer formed by laminating an iO 2 layer, an O 2 -rich layer in which a group I element is added to CdTe, and a layer in which a group I element is added to CdTe, a photoconductor layer and a light-shielding layer are formed. Peeling can be prevented.
【0040】請求項3の空間光変調素子は、TiO2とS
iO2とを交互に積層した誘電体ミラー層と遮光層との間
に、SiO2層、CdTeにI族元素が添加されたO2 リッ
チな層及びCdTeにI族元素が添加された層を積層して
なる接合層を設けることで、光導電体層と遮光層との剥
離を防止することができる。A spatial light modulator according to a third aspect is TiO 2 and S.
An SiO 2 layer, an O 2 -rich layer in which a group I element is added to CdTe, and a layer in which a group I element is added to CdTe are provided between a dielectric mirror layer and an opaque layer in which io 2 is alternately laminated. By providing the bonding layer formed by stacking layers, peeling between the photoconductor layer and the light shielding layer can be prevented.
【0041】請求項4の空間光変調素子は、空間光変調
素子の光導電体層と誘電体ミラー層との間に設ける遮光
層として、CdTe(テルル化カドミウム)にN等のV族
元素を不純物として添加したので、十分な遮光特性を有
し、しかも抵抗率が高い遮光層が得られる。したがっ
て、画像品質が良好な空間光変調素子を提供することが
できる。According to a fourth aspect of the present invention, in the spatial light modulating element, a V group element such as N is added to CdTe (cadmium telluride) as a light shielding layer provided between the photoconductor layer and the dielectric mirror layer of the spatial light modulating element. Since it is added as an impurity, a light-shielding layer having sufficient light-shielding properties and high resistivity can be obtained. Therefore, it is possible to provide a spatial light modulator having good image quality.
【0042】また、前記遮光層として、CdTeにN等の
V族元素を不純物として添加した場合には、前述のよう
に抵抗率を高くすることができるとともに、他の材料と
の密着性が良好になるので、光導電体層と遮光層との間
に及び遮光層と誘電体ミラー層との間にそれぞれ接合層
を設けなくてもよい。When CdTe is doped with a group V element such as N as an impurity as the light-shielding layer, the resistivity can be increased as described above and the adhesion with other materials is good. Therefore, it is not necessary to provide a bonding layer between the photoconductive layer and the light shielding layer and between the light shielding layer and the dielectric mirror layer.
【0043】請求項5の空間光変調素子の製造方法は、
遮光層を高周波スパッタ法によって形成する際の基板温
度を120℃〜200℃に維持し、且つスパッタ時間を
2時間以上とすることで、特別なアニール処理を行うこ
となく高抵抗の遮光層を得ることができる。A method of manufacturing a spatial light modulator according to claim 5 is
By maintaining the substrate temperature at 120 ° C. to 200 ° C. when forming the light shielding layer by the high frequency sputtering method and setting the sputtering time to 2 hours or more, a high resistance light shielding layer is obtained without performing a special annealing treatment. be able to.
【0044】請求項6の空間光変調素子の製造方法は、
基板上に誘電体ミラー層を形成した後に基板温度を12
0℃〜200℃に維持した状態で、30分〜2時間アニ
ール処理を行うことで、安定した品質の空間光変調素子
を得ることができる。更に、Cu を添加し且つ接合層を
設け更にアニールを施すことで、明・暗抵抗率の差が全
くない空間光変調素子を得ることができる。A method of manufacturing a spatial light modulator according to claim 6 is
After forming the dielectric mirror layer on the substrate, the substrate temperature is set to 12
By performing the annealing treatment for 30 minutes to 2 hours while maintaining the temperature at 0 ° C. to 200 ° C., it is possible to obtain the spatial light modulator having stable quality. Further, by adding Cu and providing a bonding layer and further annealing, it is possible to obtain a spatial light modulator having no difference in bright and dark resistivities.
【0045】請求項7の空間光変調素子の製造方法は、
遮光層を高周波スパッタ法により形成する時の基板温度
を0〜100℃とし、放電ガス圧を10〜100mTorr
とすることで、遮光層の抵抗率を108Ω・cm以上とする
ことができ、光導電体層の導電率変化を損失なく液晶に
伝えることができる。A method of manufacturing a spatial light modulator according to claim 7 is
The substrate temperature is 0 to 100 ° C. when the light shielding layer is formed by the high frequency sputtering method, and the discharge gas pressure is 10 to 100 mTorr.
By setting the above, the resistivity of the light shielding layer can be set to 10 8 Ω · cm or more, and the change in the conductivity of the photoconductor layer can be transmitted to the liquid crystal without loss.
【図1】本発明に係る空間光変調素子を組み込んだプロ
ジェクタの全体構成図FIG. 1 is an overall configuration diagram of a projector incorporating a spatial light modulator according to the present invention.
【図2】本発明に係る空間光変調素子の斜視図FIG. 2 is a perspective view of a spatial light modulator according to the present invention.
【図3】本発明に係る空間光変調素子の要部の拡大断面
図FIG. 3 is an enlarged cross-sectional view of a main part of a spatial light modulator according to the present invention.
【図4】本発明に係る別の空間光変調素子の斜視図FIG. 4 is a perspective view of another spatial light modulator according to the present invention.
【図5】別の空間光変調素子の遮光層の光学濃度を示す
図FIG. 5 is a diagram showing an optical density of a light shielding layer of another spatial light modulator.
10,30…空間光変調素子、11,21…ガラス基
板、31,36…透明基板、12,22,32,37…
透明電極、13,33…光導電体層、14,16…接合
層、14a,16c…SiO2層、14b,16b…O2
リッチなCdTe+Cu層、14c,16a…CdTe+Cu
層、15,34…遮光層、17,35…誘電体ミラー
層、23,38…液晶(光変調体)。10, 30 ... Spatial light modulators 11, 21, ... Glass substrates, 31, 36 ... Transparent substrates, 12, 22, 32, 37 ...
Transparent electrode, 13, 33 ... Photoconductor layer, 14, 16 ... Bonding layer, 14a, 16c ... SiO 2 layer, 14b, 16b ... O 2
Rich CdTe + Cu layer, 14c, 16a ... CdTe + Cu
Layers, 15, 34 ... Shading layer, 17, 35 ... Dielectric mirror layer, 23, 38 ... Liquid crystal (light modulator).
Claims (7)
報を書き込み、この書き込んだ情報に応じて光変調体を
変調させ、この光変調体に入射した読み出し光を誘電体
ミラー層によって反射せしめるようにした空間光変調素
子において、前記光導電体層と誘電体ミラー層との間に
CdTe(テルル化カドミウム)にI族元素(H,Li,
Na,K,Cu,Rb,Ag,Cs,Au,Fr)を不純物と
して添加した遮光層を設けたことを特徴とする空間光変
調素子。1. An optical writing means writes information in a photoconductor layer, modulates a light modulator in accordance with the written information, and causes a read light incident on the light modulator to be reflected by a dielectric mirror layer. In the spatial light modulation element described above, a group I element (H, Li, CdTe (cadmium telluride)) is added between the photoconductor layer and the dielectric mirror layer.
A spatial light modulator comprising a light shielding layer doped with Na, K, Cu, Rb, Ag, Cs, Au, Fr) as an impurity.
て、前記光導電体層はアモルファスシリコン層からな
り、この光導電体層と遮光層との間には接合層が設けら
れ、この接合層は光導電体層から遮光層に向かって順に
SiO2層、CdTeにI族元素が添加されたO2 リッチな
層及びCdTeにI族元素が添加された層を積層して構成
されることを特徴とする空間光変調素子。2. The spatial light modulator according to claim 1, wherein the photoconductor layer is made of an amorphous silicon layer, and a bonding layer is provided between the photoconductor layer and the light shielding layer. Is composed of a SiO 2 layer, an O 2 -rich layer in which CdTe is added with a Group I element, and a layer in which CdTe is added with a Group I element in this order from the photoconductor layer to the light-shielding layer. Characteristic spatial light modulator.
調素子において、前記誘電体ミラー層はTiO2とSiO2
とを交互に積層してなり、前記遮光層と誘電体ミラー層
との間には接合層が設けられ、この接合層は遮光層から
誘電体ミラー層に向かって順にCdTeにI族元素が添加
された層、CdTeにI族元素が添加されたO2 リッチな
層及びSiO2層を積層して構成されることを特徴とする
空間光変調素子。3. The spatial light modulator according to claim 1, wherein the dielectric mirror layer is made of TiO 2 and SiO 2.
Are alternately laminated, and a bonding layer is provided between the light shielding layer and the dielectric mirror layer. The bonding layer is formed by sequentially adding a group I element to CdTe from the light shielding layer toward the dielectric mirror layer. A spatial light modulation element comprising a laminated layer, an O 2 -rich layer in which a Group I element is added to CdTe, and a SiO 2 layer.
報を書き込み、この書き込んだ情報に応じて光変調体を
変調させ、この光変調体に入射した読み出し光を誘電体
ミラー層によって反射せしめるようにした空間光変調素
子において、前記光導電体層と誘電体ミラー層との間に
CdTe(テルル化カドミウム)にV族元素(N,P,A
s,Sb,Bi )を不純物として添加した遮光層を設けた
ことを特徴とする空間光変調素子。4. An optical writing means writes information in the photoconductor layer, modulates the light modulator in accordance with the written information, and causes the read light incident on the light modulator to be reflected by the dielectric mirror layer. In the spatial light modulating device described above, a C-group element (N, P, A) is added between CdTe (cadmium telluride) between the photoconductor layer and the dielectric mirror layer.
A spatial light modulator comprising a light-shielding layer doped with s, Sb, Bi) as an impurity.
された基板上に高周波スパッタ法によって順次、接合
層、遮光層、接合層を形成して、この接合層上に誘電体
ミラー層を形成し、この誘電体ミラー層と他の基板表面
に形成した透明電極との間に光変調体を注入するように
した空間光変調素子の製造方法において、前記高周波ス
パッタ法は基板温度を120℃〜200℃に維持して行
い、且つ遮光層生成のためのスパッタ時間は2時間以上
としたことを特徴とする空間光変調素子の製造方法。5. A bonding layer, a light shielding layer, and a bonding layer are sequentially formed by a high frequency sputtering method on a substrate on which a transparent electrode and a photoconductor layer are formed in this order, and a dielectric mirror layer is formed on the bonding layer. In the method of manufacturing a spatial light modulator in which a light modulator is formed between the dielectric mirror layer and a transparent electrode formed on the surface of another substrate, the high-frequency sputtering method uses a substrate temperature of 120 ° C. A method for manufacturing a spatial light modulator, which is performed at a temperature of up to 200 ° C. and a sputtering time for forming a light shielding layer is 2 hours or more.
法において、前記基板に誘電体ミラー層を形成した後、
基板温度を120℃〜200℃に維持した状態で、30
分〜2時間アニール処理を行うことを特徴とする空間光
変調素子の製造方法。6. The method for manufacturing a spatial light modulator according to claim 5, wherein after forming a dielectric mirror layer on the substrate,
With the substrate temperature maintained at 120 ° C to 200 ° C, 30
A method for manufacturing a spatial light modulation element, characterized by performing an annealing treatment for a period of from 2 minutes to 2 hours.
された基板上に高周波スパッタ法によって遮光層を形成
して、この遮光層上に誘電体ミラー層を形成し、この誘
電体ミラー層と他の基板表面に形成した透明電極との間
に光変調体を注入するようにした空間光変調素子の製造
方法において、前記遮光層は、基板温度を0〜100℃
とし、放電ガス圧を10〜100mTorr として形成した
ことを特徴とする空間光変調素子の製造方法。7. A light-shielding layer is formed by a high-frequency sputtering method on a substrate on which a transparent electrode and a photoconductor layer are formed in this order, and a dielectric mirror layer is formed on this light-shielding layer. In the method for manufacturing a spatial light modulator in which a light modulator is injected between a transparent electrode formed on the surface of another substrate and the transparent electrode, the light shielding layer has a substrate temperature of 0 to 100 ° C.
And a discharge gas pressure of 10 to 100 mTorr.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7036886A JP3006749B2 (en) | 1994-07-04 | 1995-02-24 | Spatial light modulator |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15236194 | 1994-07-04 | ||
JP6-152361 | 1994-07-04 | ||
JP7036886A JP3006749B2 (en) | 1994-07-04 | 1995-02-24 | Spatial light modulator |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0876140A true JPH0876140A (en) | 1996-03-22 |
JP3006749B2 JP3006749B2 (en) | 2000-02-07 |
Family
ID=26375975
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP7036886A Expired - Fee Related JP3006749B2 (en) | 1994-07-04 | 1995-02-24 | Spatial light modulator |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3006749B2 (en) |
-
1995
- 1995-02-24 JP JP7036886A patent/JP3006749B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JP3006749B2 (en) | 2000-02-07 |
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