DE102004042175A1 - Sensor element for converting radiation energy into an electric signal has a semiconductor component/transistor with an active semiconductor material area as a sensor zone - Google Patents

Abstract

A semiconductor component/transistor (T) has an active semiconductor material area (A) as a sensor zone (SZ). The active semiconductor material area in the sensor zone is created from/with an organic semiconductor material (70). The transistor is formed on a substrate's (20) surface area (20a) and has a gate area (G) made from a gate material (30) embedded in gate insulation (GOX).

Description

The The present invention relates to a sensor element and to a device formed sensor.

at the construction of sensor elements for the conversion of radiant energy in an electrical signal z. B. Semiconductor devices used, to make the conversion process particularly easy and reliable shape. Although conventional Semiconductor devices and their integration into sensor elements and Sensors based on conventional Semiconductor technologies offer a wide range of applications arising due to increasing customer demands and because of the need for greater flexibility in terms of desired Material combinations requirement profiles, which are conventional Semiconductor materials can not meet.

Of the Invention is therefore based on the object, a sensor element and to create a sensor with unchanged reliability and sensitivity particularly versatile and used in existing device concepts can be integrated.

Is solved the object underlying the invention by a sensor element with the characteristics of the independent Claim 1. Solved The object underlying the invention is further by a Sensor having the features of independent claim 17. Advantageous developments of the sensor element according to the invention and the inventive sensor are each subject of the dependent Dependent claims.

The inventive sensor element is for converting radiant energy into an electrical signal formed and has for this purpose at least one semiconductor device, which in turn has an active semiconductor material area as Sensor zone has. According to the invention, the semiconductor material region the sensor zone made of or with an organic semiconductor material educated.

By the inventive provision an organic semiconductor material as a constituent or as a base material for the active semiconductor material region of the sensor zone results advanced and in terms of applications and processing mechanisms particularly flexible sensor element.

It can additionally be provided that the active semiconductor material region of the sensor zone is acted upon by radiation and that the active semiconductor material area the sensor zone when exposed to radiation in a certain detection energy range from a state with a comparatively lower electrical conductivity to a state with a comparatively higher electrical conductivity can be transferred.

at a preferred alternative of the sensor element according to the invention, it is provided that the active semiconductor material region of the sensor zone substantially can be acted upon directly by external radiation to be detected.

alternative For this purpose, it is provided that the active semiconductor material area the sensor zone is not directly with external radiation to be detected can be acted upon.

Under a direct application is understood below to mean a process in which the radiation to be detected as such on the active Semiconductor material region of the sensor zone occurs, with a change the radiation characteristics, except in terms of intensity and phase, not meant to be included. Under an indirect charge of the active semiconductor material region of the sensor zone to be detected Radiation is understood to be exposure to radiation, which was derived from the radiation to be detected, z. B. by Frequency conversion from a higher frequency Range in a lower frequency range or by conversion of a kind of radiation, e.g. B. particle or corpuscular radiation, in a different kind of radiation, e.g. B. electromagnetic radiation.

at the embodiments, where no direct loading of the active semiconductor material region the sensor zone with radiation to be detected provided externally It is advantageous that the active semiconductor material layer or the active semiconductor material region of the sensor zone with a Material area is covered or embedded in these.

there it is particularly advantageous if the active semiconductor material region the sensor zone covering or embedding material area a transducer material has or is formed from such, through which the radiation to be detected essentially directly as primary radiation receivable and convertible into secondary radiation and substantially to the active semiconductor material region of the sensor zone can be emitted, especially in the detection energy range of the active Semiconductor material region of the sensor zone.

In another alternative or add According to the embodiment of the sensor element according to the invention, a substrate is provided with a surface area, wherein the semicon terbauelement is formed on or above the surface region of the substrate.

In In this case, it is provided that the active semiconductor material area the sensor zone of the surface facing the surface region of the substrate Spaces directly or indirectly with radiation to be detected can be acted upon.

In In this case it is of particular advantage, if necessary trainee transducer material above the surface area of the substrate is formed.

alternative it can be provided that the active semiconductor material area the sensor zone of the surface facing away from the surface region of the substrate Spaces directly or indirectly with radiation to be detected can be acted upon, ie in particular from a bottom of the substrate ago.

In In this case it is of particular advantage, if necessary to be provided transducer material below the surface area the substrate is provided, in particular on or below the Bottom of the substrate.

In these cases it is particularly advantageous if the substrate itself for the nachweisende Radiation, so for the primary radiation, or for the secondary radiation is formed substantially transparent.

at another alternative or additional embodiment of the sensor element according to the invention it is provided that the semiconductor device as a transistor is formed, whose channel region is formed by or with the active semiconductor material region of the sensor zone. this means in particular, that the channel region of the transistor with or is formed of an organic semiconductor material.

at an alternative embodiment of the sensor element according to the invention On the other hand, it is envisaged that the underlying semiconductor device is formed as a diode whose cathode region and / or their Anode region is formed by or with the active semiconductor material region the sensor zone. This means in particular that the cathode area and / or that the anode region of the diode with or from an organic Semiconductor material is or are formed.

In In this case is advantageously additionally a selection transistor provided in electrical connection with the diode to thereby to create an active sensor element.

From It is particularly advantageous in this case that the additional selection transistor as organic field effect transistor is formed, the channel region is formed with an organic semiconductor material. It can the organic semiconductor material region for the selection transistor and the organic semiconductor material region for the diode is identical or also be different.

to electrical contacting of the diode with the selection transistor is it is especially provided that the cathode region or the anode region the diode to the source region or the drain region of the selection transistor connected is.

One Another aspect of the present invention is a Sensor for converting radiant energy into an electrical signal provide. According to the invention, this sensor with a plurality of sensor elements according to the invention educated.

at a particularly advantageous embodiment of the sensor according to the invention the sensor elements are connected in such a way that by them from each other independent electrical signals to the reception of a corresponding radiation can be generated.

at another advantageous additional or alternative embodiment the sensor according to the invention it is envisaged that the majority of sensors in a one-dimensional Sequence is arranged, in particular in essence linear and / or in a substantially planar form. It may be in this case, a sequence in the form of a straight line act that lies in a certain level. Are conceivable but also curved one-dimensional arrangements, either in a planar plane lie or even on a curved or curved surface.

alternative For this purpose, it is conceivable that the plurality of sensor elements of the sensor according to the invention are arranged in a two-dimensional arrangement, in particular as a matrix, in rectangular form and / or in planar form.

Further It is advantageous if the sensor is designed as an image sensor. This sets a specific arrangement of the individual sensor elements and their interconnection preceded, being a planar and rectangular Matrix arrangement with independent interconnected sensor elements is of particular advantage.

Hereinafter these and other aspects of the present invention will be further explained:
The present invention particularly relates to arrangements for the realization of active image sensors for digitizing photonic information by means of organic field effect transistors.

The Production of large-scale image sensors for two-dimensional imaging of photonic information (including X-rays, UV radiation, visible light, near infrared, infrared) requires one hand optionally the conversion of the corresponding photonic radiations into an electronically evaluable form (for example, the transformation of X-ray quanta in visible light) and on the other hand the conversion of these electronically evaluable radiation in a two-dimensional detector matrix in electronic signals. For this purpose, the sensor surface is so divided into individual picture elements or so-called pixels that the image information of each pixel electronically resolved and detected can be. To the many individual pixels electronically from each other To decouple, it is usually necessary in every single one Pixel to integrate a selection transistor. This form of image sensor is also called active matrix "active matrix image sensor ", unlike a passive matrix, where the pixels do not have select transistors feature.

Here should different integration variants and production possibilities active image sensors based on organic field effect transistors and optionally using organic photodiodes in combination with optionally necessary converters, for example scintillators for Conversion of X-ray quanta in visible or ultraviolet light. critical is the potentially inexpensive realization of such active Image sensors on large surfaces and the possibility thanks to those used in the manufacture of organic semiconductor devices relatively low process temperatures, usually below about 200 ° C, to realize the sensors on flexible substrates.

At present, active image sensors are manufactured exclusively on the basis of silicon, in either single-crystalline, polycrystalline or amorphous form. The implementation of a commercially available two-dimensional image sensor based on photodiodes and selection transistors based on amorphous silicon on a glass substrate is disclosed in US Pat 1A to 1C see also [1], where an embodiment of a known two-dimensional image sensor based on photodiodes and selection transistors based on amorphous silicon is shown.

These Production of large-scale image sensors On the basis of silicon is relatively expensive and expensive and requires relatively high process temperatures during production, usually above about 300 ° C. For this reason, the production of such image sensors is flexible Substrates, so on polymer films, which is usually a glass transition temperature below 150 ° C currently not feasible.

method for the realization of large-scale image sensors on the basis of organic semiconductor devices, that is, on the basis of organic field effect transistors or organic Photodiodes are currently unknown.

The The invention describes arrangements and integration concepts for implementation active image sensors for one- or two-dimensional detection of photonic Information using organic field effect transistors. there forms a matrix consisting of organic field effect transistors the basic component for generating and local allocation of electronic Information.

2 shows the simplified circuit diagram of a possible implementation of a two-dimensional active image sensor based on organic transistors using a control of the sensor elements via constant current sources. Each of the transistors simultaneously performs two tasks, namely that of a sensor element, and that of a switch for addressing the individual pixels within the matrix, that is, that of a selection transistor.

• (a) Direkte Umwandlung photonischer Information in digitale Information (Primärstrahlun, Primärsignal) Bei diesem Konzept wird ausgenutzt, dass sich der Drainstrom eines organischen Feldeffekttransistors bei Bestrahlung des Transistors erhöht, sofern die Wellenlänge der Strahlung in das Absorptionsspektrums des organischen Halbleiters fällt. Die Absorption von Photonen im organischen Halbleiter führt zur Generation von Ladungsträgerpaaren, die zum Drainstrom beitragen. Dieses Konzept beschränkt sich in der Regel auf einen relativ kleinen Wellenlängenbereich der photonischen Informationen als Primärsignal oder Primärstrahlung. Außerdem eignet sich dieses Konzept bevorzugt zum Aufbau von Einzelsensoren, weil ein Auslesen in einer Matrixanordnung ohne Zwischenspeichern der Information nicht zuverlässig erfolgen kann.
• (b) Direkte Umwandlung photonischer Information in digitale Information mit Fotodiode (Primärstrahlung, Primärsignal) Bei diesem Konzept wird ausgenutzt, dass sich die über einer organischen Fotodiode anstehende Spannung bei Bestrahlung der Diode ändert, sofern die Wellenlänge der Strahlung in das Absorptionsspektrums des organischen Halbleiters fällt. Die Absorption von Photonen im organischen Halbleiter führt zur Generation von Ladungsträgerpaaren, die unter dem Einfluss des internen elektrischen Feldes getrennt und zu den Elektroden abgeführt werden, wo sie die über der Diode anstehende Spannung verändern. Dieses Konzept beschränkt sich in der Regel auf einen relativ kleinen Wellenlängenbereich der photonischen Informationen als Primärsignal oder Primärstrahlung. Die Photodiode stellt gleichzeitig eine Kapazität dar, an der die getrennten und abgeführten Ladungen und damit die elektronische Information so lange gespeichert bleiben, bis das Auslesen über den Auswahltransistor erfolgt. Zu diesem Zweck muss die Fotodiode in elektrischen Kontakt zum Transistor stehen. Die zu detektierenden Wellenlängen der photonischen Information werden von den Eigenschaften der organischen Halbleiterschicht(en) der Diode bestimmt. Im Allgemeinen lassen sich mit dieser Anordnung photonische Informationen vom UV-Bereich bis zum NIR-Bereich detektieren und digitalisieren. Eine Anpassung der Absorptionseigenschaften des Diodenmaterials ist in Grenzen mit Hilfe von Sensibilisatorfarbstoffen möglich.
• (c) Indirekte Umwandlung photonischer Information in digitale Information (Sekundärstrahlung, Sekundärsignal) Auch bei diesem Konzept wird ausgenutzt, dass sich der Drainstrom eines organischen Feldeffekttransistors bei Bestrahlung des Transistors erhöht, sofern die Wellenlänge der Strahlung in das Absorptionsspektrums des organischen Halbleiters fällt. Um eine Erfassung photonischer Informationen als Primärsignal oder Primärstrahlung zu ermöglichen, deren Wellenlänge außerhalb des Absorptionsspektrums des organischen Halbleiters liegt, zum Beispiel Röntgenstrahlung oder tiefes UV, erfolgt zunächst eine Umwandlung dieser kurzwelligen Primärstrahlung in eine geeignete Sekundärstrahlung. Hierfür ist die Integration entsprechender Wandler erforderlich. Diese müssen – ähnlich wie die Primärquelle in Konzepten (a) und (b) – zwar nicht in elektrischem Kontakt zum Transistor stehen, jedoch in optischem oder Sichtkontakt, so dass die Sekundärstrahlung als Sekundärinformation detektiert werden kann. Entsprechende Materialien für Wandler sind für eine Vielzahl von Primärsignalen bekannt. Ein Beispiel sind Cäsium-Jodid-Schichten für die Umwandlung von Röntgenstrahlung in sichtbares Licht. Dieses Konzept eignet sich bevorzugt zum Aufbau von Einzelsensoren, weil ein Auslesen in einer Matrixanordnung ohne Zwischenspeichern der Information nicht zuverlässig erfolgen kann.
• (d) Indirekte Umwandlung photonischer Information in digitale Information mit Fotodiode (Sekundärstrahlung, Sekundärsignal) Auch bei diesem Konzept wird ausgenutzt, dass sich die über einer organischen Fotodiode anstehende Spannung bei Bestrahlung der Diode ändert, sofern die Wellenlänge der Strahlung in das Absorptionsspektrums des organischen Halbleiters fällt. Um eine Erfassung photonischer Informationen als Primärsignal oder Primärstrahlung zu ermöglichen, deren Wellenlänge außerhalb des Absorptionsspektrums des organischen Halbleiters liegt, zum Beispiel Röntgenstrahlung oder tiefes UV, erfolgt zunächst eine Umwandlung dieser kurzwelligen Primärstrahlung in eine geeignete Sekundärstrahlung. Hierfür ist die Integration entsprechender Wandler erforderlich.

In the following, different integration concepts for the realization of active image sensors with organic components are presented:

• (a) Direct conversion of photonic information into digital information (primary beam, primary signal) This concept utilizes that the drain current of an organic field effect transistor increases upon irradiation of the transistor as long as the wavelength of the radiation falls within the absorption spectrum of the organic semiconductor. The absorption of photons in the organic semiconductor leads to the generation of charge carrier pairs that contribute to the drain current. This concept is usually limited to a relatively small wavelength range of the photonic information as a primary signal or primary radiation. In addition, this concept is preferably suitable for the construction of individual sensors, because read-out in a matrix arrangement without temporary storage of the information can not be reliable.
• (b) Direct conversion of photonic information into digital information with a photodiode (primary radiation, primary signal) This concept makes use of the fact that the photoswitches that are present above an organic photodiode are exploited Voltage upon irradiation of the diode changes as long as the wavelength of the radiation falls within the absorption spectrum of the organic semiconductor. The absorption of photons in the organic semiconductor leads to the generation of pairs of charge carriers, which are separated under the influence of the internal electric field and dissipated to the electrodes, where they change the voltage across the diode. This concept is usually limited to a relatively small wavelength range of the photonic information as a primary signal or primary radiation. At the same time, the photodiode represents a capacitance at which the separated and discharged charges and thus the electronic information remain stored until reading takes place via the selection transistor. For this purpose, the photodiode must be in electrical contact with the transistor. The wavelengths of the photonic information to be detected are determined by the properties of the organic semiconductor layer (s) of the diode. In general, photonic information from the UV region to the NIR region can be detected and digitized with this arrangement. An adaptation of the absorption properties of the diode material is possible within limits with the help of sensitizer dyes.
• (c) Indirect conversion of photonic information into digital information (secondary radiation, secondary signal) Also in this concept, the drain current of an organic field effect transistor is increased when the transistor is irradiated, as long as the wavelength of the radiation falls within the absorption spectrum of the organic semiconductor. In order to enable detection of photonic information as a primary signal or primary radiation whose wavelength is outside the absorption spectrum of the organic semiconductor, for example X-radiation or deep UV, a conversion of this short-wave primary radiation into a suitable secondary radiation takes place first. This requires the integration of appropriate transducers. These must - like the primary source in concepts (a) and (b) - not be in electrical contact with the transistor, but in optical or visual contact, so that the secondary radiation can be detected as secondary information. Corresponding materials for transducers are known for a variety of primary signals. An example is cesium-iodide layers for the conversion of X-rays into visible light. This concept is preferably suitable for the construction of individual sensors, because read-out in a matrix arrangement without temporary storage of the information can not take place reliably.
• (d) Indirect conversion of photonic information into digital information with photodiode (secondary radiation, secondary signal) This concept also exploits the fact that the voltage across an organic photodiode changes when the diode is irradiated, as long as the wavelength of the radiation into the absorption spectrum of the organic semiconductor falls. In order to enable detection of photonic information as a primary signal or primary radiation whose wavelength is outside the absorption spectrum of the organic semiconductor, for example X-radiation or deep UV, a conversion of this short-wave primary radiation into a suitable secondary radiation takes place first. This requires the integration of appropriate transducers.

The principal challenge is the integration of the individual components, namely an organic transistor, a photodiode, a transducer, on the substrate while ensuring the functionality and the procedural feasibility. It is important to take into account that the selection transistors and the transmitter with the possibly necessary photodiodes are in electrical contact have to, while the photonic information, namely the primary and the secondary information and thus also possibly required converter only in optical contact or visual contact with the transistor and diode must be, where the distance between the transducer and the photodetector in the interest of the resolution is not to be too big allowed to avoid stray light effects.

integration concepts

Out These requirements arise for the integration of the individual components to active image sensors in principle two possibilities

On the one hand, the realization of an image sensor on an arbitrary and not necessarily transparent substrate is conceivable with coupling of the radiation either directly via the source or indirectly via a transducer from the front side in accordance with FIGS 3A to 3D ,

On the other hand, the realization of an image sensor on a transparent substrate is conceivable with coupling of the radiation either directly via the source or indirectly via a transducer from the rear side in accordance with FIGS 4A to 4D , In this case, the lower electrodes of the light absorbing devices must be realized by using an optically sufficiently transparent electrically conductive layer. For example, very thin metal layers, conductive polymers and / or transparent metal oxides, for example tin oxide and zinc oxide, are suitable for this purpose.

For targeted reduction of Lichtstreuef For all described integration concepts, the use of a dark matrix or dark mask, ie a strongly absorbing layer, which is only in the region of the sensors or the actual sensor zone, ie depending on the concept either in the transistor or in the Photodiode, opened, beneficial.

in principle is next to the planar array of select transistor and photodiode according to the embodiments 3B and 3D also possible a stacking of the individual components, wherein the photodiode is arranged either above or below the transistor can be. In the arrangement of the transistor above the photodiode Although it reduces the available for absorption in the photodiode Area. However, this is not a problem, because the photodiode usually anyway much larger as the transistor.

A Core idea of the invention is therefore also in particular in the provision of arrangements for the realization of one- and two-dimensional active image sensors for the digitization of photonic information with the help of organic field effect transistors as part of a active matrix.

These and further aspects of the present invention will become more apparent by way of schematic Drawings based on preferred embodiments of the invention explained in more detail.

1A -C show in schematic plan view, in the form of a circuit diagram or in a sectional side view embodiments of conventional sensor elements.

2 shows in the form of a schematic circuit diagram of a sensor according to the invention of a plurality of matrix-like arranged inventive sensor elements according to a preferred embodiment of the invention.

3A D show schematic and sectional side views of various embodiments of inventive sensor elements with front side irradiation with respect to a given substrate.

4A D show schematic and sectional side views of various embodiments of inventive sensor elements with backside irradiation with respect to a given substrate.

following become functionally and / or structurally similar or equivalent Elements denoted by the same reference numerals without being in any Case of their occurrence a detailed description is repeated.

The 1A to 1C illustrate the arrangement for a conventional sensor for converting radiant energy into an electrical signal. The 1A shows in plan view the design for an arrangement of conventional sensor elements in strict semiconductor technology. 1C is a schematic and sectional side view of a single sensor element of the prior art. 1B shows in schematic form of a circuit diagram of the structure of the sensor element 1C , namely consisting of a so-called photodiode and a thin-film transistor TFT.

2 is a schematic circuit diagram of a sensor according to the invention 100 with a plurality of sensor elements according to the invention 10 , which are essentially each formed by organic transistors T and matrix-like, that is arranged in the form of a rectangular and planar matrix, wherein the access and the control of the individual sensor elements 10 based on a drive and measurement unit 10 and a row decoder 120 and corresponding access lines 111 respectively. 121 takes place, wherein in the control and measuring lines 111 as access lines 111 In addition, power sources Q are provided.

The 3A to 4D show in schematic and sectional side view preferred embodiments of the sensor element according to the invention 10 ,

In the embodiment of the sensor element according to the invention 10 according to the 3A is provided as the underlying semiconductor device T T a transistor. The transistor T is on the surface area 20a a substrate 20 formed and has a gate region G of a gate material 30 which is in a gate insulation GOX made of an insulating material 40 is embedded and to which first and second source / drain regions SD1, SD2 from a source / drain material 50 connect, wherein a certain area of the gate insulation GOX remains free in the form of a window F and of an organic semiconductor material 70 is occupied and filled, which forms the channel region K of the transistor T between the first and the second source / drain region SD1, SD2 and in this embodiment also the active semiconductor material region A of the sensor zone SZ.

The structure of gate region G, gate insulation GOX, first and second source / drain regions SD1, SD2 and channel region K is in a buffer material region 60 embedded, which at its upper page 60a leaving the window F for radiation entry with a dark matrix 80 is covered.

In operation falls through the window F and through the buffer layer 60 through detection radiation in a direct manner to the organic semiconductor material 70 the channel region K of the transistor T, namely as a primary radiation hν and causes in the material 70 of the channel region K of the transistor T as an active semiconductor material region A of the sensor zone SZ a transition from a state of comparatively lower electrical conductivity to a state of comparatively higher electrical conductivity, so that via a channel current between the first source / drain region SD1 and the second source / Drain region SD2 through the channel K of the transistor T, the detection of the primary radiation can take place. The prerequisite is that for the primary radiation hν the buffer material 60 is essentially transparent and that the semiconductor material 70 of the channel region K of the transistor T as the active semiconductor material region A of the sensor zone SZ fits energetically with its detection energy range to the primary radiation hν.

In the embodiment of the 3A is the underlying semiconductor device T of the sensor element 10 that is, as a single transistor T based on an organic semiconductor material 70 trained and on the surface 20a of the underlying substrate 20 arranged, wherein the semiconductor device T, the primary radiation hν directly and from the surface area 20a receives the space facing the substrate area and detects.

In the embodiment of the sensor element according to the invention 10 according to the 3B is also provided as the underlying semiconductor device T, a transistor T. The transistor T is on the surface area 20a a substrate 20 formed and has a gate region G of a gate material 30 which is in a gate insulation GOX made of an insulating material 40 is embedded and to which first and second source / drain regions SD1, SD2 from a source / drain material 50 connect, wherein a certain area of the gate insulation GOX remains free in the form of a window F and of an organic semiconductor material 70 is occupied and filled, which forms the channel region K of the transistor T between the first and the second source / drain region SD1, SD2 and in this embodiment also the active semiconductor material region A of the sensor zone SZ.

The structure of gate region G, gate insulation GOX, first and second source / drain regions SD1, SD2 and channel region K is in a buffer material region 60 embedded, which at its top 60a leaving the window F for radiation entry with a dark matrix 80 is covered.

On the buffer layer 60 in the area of the window F and on the dark matrix 80 is a transducer material 90 applied, by which the primary radiation hν 'receivable, in secondary radiation hν' convertible and in the direction of the active semiconductor material region A of the sensor zone SZ, namely the organic semiconductor material region 70 of the channel area 70 of the transistor T as secondary radiation hν 'can be emitted.

In operation falls through the window F and through the buffer layer 60 through the detection radiation, but in an indirect manner, to the organic semiconductor material 70 the channel region K of the transistor T, namely as secondary radiation hν 'and causes in the material 70 of the channel region K of the transistor T as an active semiconductor material region A of the sensor zone SZ a transition from a state of comparatively lower electrical conductivity to a state of comparatively higher electrical conductivity, so that via a channel current between the first source / drain region SD1 and the second source / Drain region SD2 through the channel K of the transistor T, the detection of the primary radiation hν on the detection of the secondary radiation hν 'can take place. The prerequisite is that for the secondary radiation hν 'the buffer material 60 is essentially transparent and that the semiconductor material 70 of the channel region K of the transistor T as an active semiconductor material region A of the sensor zone SZ energetically fits with its detection energy range to the secondary radiation hν '.

The embodiment of the 3B differs from the embodiment of the 3A thus essentially by the fact that in the organic semiconductor material area 70 of the Ka nalbereichs K of the underlying semiconductor device T, the primary radiation hν on the secondary radiation hν 'from the conversion process by the transducer material 90 is detected.

In the embodiment of the sensor element according to the invention 10 according to the 3C is provided as the underlying semiconductor device D, a diode D. This diode D defines the actual sensor zone SZ with a corresponding active semiconductor material region A, the latter being formed by the anode region An and / or the cathode region Ka of the diode D. The anode region An is with or made of an organic semiconductor material 75 formed, the cathode region of a corresponding cathode material 76 , In this embodiment of the sensor element 10 lies the cathode area Ka directly on the surface 20a a substrate 20 on. This is followed by the anode region adjoins the diode D, which is designed for radiation reception and detection and is electrically connected to the selection transistor T.

The transistor T is also on the surface area 20a of the substrate 20 formed and has a gate region G of a gate material 30 which is in a gate insulation GOX made of an insulating material 40 is embedded and to which first and second source / drain regions SD1, SD2 from a source / drain material 50 connect, wherein a certain area of the gate insulation GOX remains free in the form of a window F and of an organic semiconductor material 70 is taken and filled, which the channel region K of the transistor T between the first and the second source / drain region SD1, SD2 and in this embodiment does not form the active semiconductor material region A of the sensor zone SZ.

The diode D and the selection transistor are in a buffer layer 60 embedded. That is, the structure of gate region G, gate insulation GOX, first and second source / drain regions SD1, SD2 and channel region K on the one hand, and cathode region Ka and anode region on the other hand, is in a buffer material region 60 embedded, which at its top 60a leaving a window F for radiation entry with a dark matrix 80 is covered. The dark matrix 80 covers or shadows the transistor T substantially, whereas the diode D is located as a detection element with the sensor zone SZ under the window.

In operation falls through the window F and through the buffer layer 60 through detection radiation in a direct manner to the organic semiconductor material 75 of the anode region At the diode D, namely as the primary radiation hν and causes in the material 75 at least of the anode region at the diode D as the active semiconductor material region A of the sensor zone SZ a transition from a state with comparatively lower electrical conductivity to a state with comparatively higher electrical conductivity, so that via a diode current and when selecting a corresponding channel current between the first source / Drain region SD1 and the second source / drain region SD2 through the channel K of the transistor T, the detection of the primary radiation hν can be made directly. The prerequisite is that for the primary radiation hν the buffer material 60 is essentially transparent and that the semiconductor material 75 of the anode region At the diode D, as the active semiconductor material region A of the sensor zone SZ, it fits energetically with its detection energy range to the primary radiation hν.

In the embodiment of the 3C So is in addition to the elements of the embodiment of 3A as the underlying semiconductor device D, which defines the sensor zone SZ and the active semiconductor material region A, a diode D is provided, which at least in part, namely in its anode region An from or with an organic semiconductor material 75 exists as an active semiconductor material region A of the sensor zone SZ, wherein the likewise provided transistor T is an organic field effect transistor and through the dark mask 80 or dark matrix 80 is completely shadowed, so that in the embodiment of the 3C the primary radiation hν in a direct manner exclusively on the organic semiconductor material area 75 the underlying diode D strikes as an active semiconductor material region A or sensor zone SZ and is detected there.

In the embodiment of the sensor element according to the invention 10 according to the 3D is provided as the underlying semiconductor device D also has a diode D. This diode D defines the actual sensor zone SZ with a corresponding active semiconductor material region A, the latter being formed by the anode region An and / or the cathode region Ka of the diode. The anode region An is with or of an organic semiconductor material 75 formed, the cathode region of a corresponding cathode material 76 , In this embodiment of the sensor element 10 the cathode region Ka lies directly on the surface 20a a substrate 20 on. This is followed by the anode region adjoins the diode D, which is designed for radiation reception and detection and is electrically connected to the selection transistor T.

The transistor T is also on the surface area 20a of the substrate 20 formed and has a gate region G of a gate material 30 which is in a gate insulation GOX made of an insulating material 40 is embedded and to which first and second source / drain regions SD1, SD2 from a source / drain material 50 connect, wherein a certain area of the gate insulation GOX remains free in the form of a window F and of an organic semiconductor material 70 is taken and filled, which the channel region K of the transistor T between the first and the second source / drain region SD1, SD2 and in this embodiment does not form the active semiconductor material region A of the sensor zone SZ.

The diode D and the selection transistor are in a buffer layer 60 embedded. That is, the structure of gate region G, gate insulation GOX, first and second source / drain regions SD1, SD2 and channel region K on the one hand, and cathode region Ka and anode region on the other, is in a buffer material region 60 embedded, which at its top 60a leaving a window F for radiation entry with a dark matrix 80 is covered. The dark matrix 80 covers or shadows the transistor T substantially, whereas the diode D is located as a detection element with the sensor zone SZ under the window.

On the buffer layer 60 in the area of the window F and on the dark matrix 80 is a transducer material 90 applied, by which the primary radiation hν 'receivable, in secondary radiation hν' convertible and in the direction of the active semiconductor material region A of the sensor zone SZ, namely the organic semiconductor material region 75 of the anode region can be emitted at the diode D as secondary radiation hν '.

In operation falls through the window F and through the buffer layer 60 through detection radiation, but in an indirect manner, to the organic semiconductor material 75 of the anode region At the diode D, namely as secondary radiation hν 'and causes in the material 75 at least of the anode region at the diode D as the active semiconductor material region A of the sensor zone SZ a transition from a state with comparatively lower electrical conductivity to a state with comparatively higher electrical conductivity, so that via a diode current and when selecting a corresponding channel current between the first source / Drain region SD1 and the second source / drain region SD2 through the channel K of the transistor T, the detection of the primary radiation hν can be done indirectly via the detection of the secondary radiation hν '. The prerequisite is that for the secondary radiation hν 'the buffer material 60 is essentially transparent and that the semiconductor material 75 of the anode region at the diode D as an active semiconductor material region A of the sensor zone SZ energetically with its detection energy range to the secondary radiation hν 'fits.

The embodiment of the 3D differs from the embodiment of the 3C in other words essentially in that here the secondary radiation hν 'in the organic semiconductor material 75 the diode D is detected as the underlying semiconductor device D as the active semiconductor material region A of the sensor zone SZ, which of the transducer material 90 is generated from the primary radiation hυ, which the window area F in the dark mask or dark matrix 80 covers.

The embodiment of the 4A differs from the embodiment of the 3A exclusively in that the reception of the primary radiation hν by the sensor element 10 from the bottom 20b of the substrate 20 is done here, the bottom 20b of the substrate 20 with the dark mask 80 or dark matrix 80 covered with appropriate release by means of a window F. In doing so, the substrate must 20 and also the subsequent layers of material between the sub strate 20 and the organic semiconductor material region 70 be substantially transparent to the primary radiation hν.

The embodiment of the 4B differs from the embodiment of the 4A exclusively in that in the region of the window F is a buffer material layer 60 and a transducer material layer 90 connect the latter, the primary radiation hν in a secondary radiation hν 'converts their energy in the detection energy range of the organic semiconductor material 70 the channel region K of serving as the underlying semiconductor device T organic transistor T is used.

The embodiment of the 4C differs from the embodiment of the 3C essentially in that the reception of the primary radiation hν from the bottom 20b of the substrate 20 is done here, the bottom 20b of the substrate 20 accordingly with the dark mask 80 or dark matrix 80 is covered with the release of a window F in the region of the diode D. Also here must be the substrate 20 as well as those materials between the substrate 20 and the organic semiconductor material layer 75 the diode D are provided as an active semiconductor material region A of the sensor zone SZ, be substantially transparent to the primary radiation hν.

The embodiment of the 4D Finally, it differs from the embodiment of the 4C essentially in that essentially the area of the window F of the dark matrix 80 or dark mask 80 , a buffer material layer 60 and a transducer material layer 90 are provided in this order, the latter for converting the primary radiation hν into a secondary radiation hν 'and for their emission to the organic semiconductor material region 75 the diode D is formed.

Quoted literature

• [1] R.A. Street, "Technology and Applications of Amorphous Silicon, "Springer Publisher, 2000.

10

inventive sensor element

20

substratum

20a

Surface area, top

20b

bottom

30

material area for gate electrode

40

material area for gate insulation

50

material area for source / drain regions

60

Buffer material area

70

organic Semiconductor material

especially for transistor

75

organic Semiconductor material

especially for diode

80

material for dark mask / Dunkeklmatrix

90

Transducer material area

100

inventive sensor

110

actuation and measurement unit

111

actuation and measuring line

120

row decoder

121

drive line

A

active Semiconductor material region

At

Anode, Anode region of the diode D

D

diode

G

Gate electrode, gate

GOX

gate insulation

K

channel area

ka

Cathode, Cathode region of the diode D

Q

power source

SD1

Source / drain region

SD2

Source / drain region

SZ

sensor zone

T

transistor

hv

primary radiation

hv '

secondary radiation

Claims (21)

Sensor element, which is designed for converting radiant energy into an electrical signal and which has at least one semiconductor component (T, D) each having an active semiconductor material region (A) as sensor zone (SZ) or as part thereof, wherein the active semiconductor material region (A) the sensor zone (SZ) made of or with an organic semiconductor material ( 70 . 75 ) is trained. Sensor element according to claim 1, - in which the active semiconductor material region (A) of the sensor zone (SZ) with Radiation is acted upon and In which the active semiconductor material region (A) the sensor zone (SZ) when exposed to radiation in a certain Detecting energy range from a state with a lower electrical conductivity to a state of higher electrical conductivity is feasible. Sensor element according to one of the preceding claims, in which is the active semiconductor material region (A) of the sensor zone (SZ) essentially directly with external radiation to be detected can be acted upon. Sensor element according to one of the preceding claims 1 to 3, in which the active semiconductor material region (A) of the sensor zone (SZ) can not be exposed directly to external radiation to be detected is. Sensor element according to Claim 4, in which the active semiconductor material (A) of the sensor zone (SZ) has a material region (SZ). 19 ) is covered or embedded in these. Sensor element according to Claim 5, - in which the material region covering or embedding the active semiconductor material region (A) of the sensor zone (SZ) ( 19 ) a transducer material ( 90 ), by which the radiation to be detected is substantially directly receivable as primary radiation and convertible into secondary radiation and substantially to the active semiconductor material region (A) of the sensor zone (SZ), in particular in the detection energy range of the active semiconductor material region (A) of the sensor zone (SZ). Sensor element according to one of the preceding claims, - in which a substrate ( 20 ) with a surface area ( 20a ) is provided, - wherein the semiconductor component (T, D) on or above the surface area ( 20a ) of the substrate ( 20 ) is trained. Sensor element according to Claim 7, in which the active semiconductor material region (A) of the sensor zone (SZ) differs from the surface region (S). 20a ) of the substrate ( 20 ) facing space directly forth directly or indirectly with detectable radiation is acted upon. Sensor element according to claim 8, wherein the transducer material ( 90 ) above the surface area ( 20a ) of the substrate ( 20 ) is provided. Sensor element according to Claim 7, in which the active semiconductor material region (A) of the sensor zone (SZ) differs from the surface region (S). 20a ) of the substrate ( 20 ) remote space can be acted upon direct or indirect radiation to be detected, wherein the substrate ( 20 ) is formed substantially transparent in particular for the radiation to be detected. Sensor element according to claim 10, wherein the transducer material ( 90 ) below the upper area ( 20a ) of the substrate ( 20 ) is provided. Sensor element according to one of the preceding claims, in in which the semiconductor component (T, D) is designed as a transistor (T) is whose channel region (K) is formed by or with the active Semiconductor material region (A) of the sensor zone (SZ). Sensor element according to one of the preceding claims 1 to 12, in which the semiconductor device (T; D) is formed as a diode (D) is whose cathode region (Ka) and / or its anode region (An) is formed or are of or with the active semiconductor material region (A) the sensor zone (SZ). Sensor element according to claim 13, wherein additionally a Selection transistor (T) in electrical connection with the diode (T) is provided. Sensor element according to Claim 14, in which the selection transistor (T) is designed as an organic field-effect transistor whose channel region (K) is formed with an organic semiconductor material ( 70 ) is formed. Sensor element according to one of the preceding claims 14 or 15, in which either the cathode region (Ka) or the Anode region (An) of the diode (D) to the source region (SD1) or the drain region (SD2) of the selection transistor (T) is electrically connected is. Sensor for converting radiant energy into an electrical signal, in which a plurality of sensor elements ( 10 ) is provided according to one of claims 1 to 16. Sensor according to Claim 17, in which the sensor elements ( 10 ) are interconnected to form mutually independent electrical signals. Sensor according to one of the preceding claims 17 or 18, wherein the plurality of sensors ( 10 ) is arranged in a one-dimensional juxtaposition, in particular in linear and / or in planar form. Sensor according to one of the preceding claims 17 to 19, wherein the plurality of sensor elements ( 10 ) is arranged in a two-dimensional arrangement, in particular as a matrix, in a rectangular shape and / or in planar form. Sensor according to one of the preceding claims 17 to 20, which is designed as an image sensor.