[go: up one dir, main page]

WO1998021756A1 - Sensor element - Google Patents

Sensor element Download PDF

Info

Publication number
WO1998021756A1
WO1998021756A1 PCT/EP1996/004947 EP9604947W WO9821756A1 WO 1998021756 A1 WO1998021756 A1 WO 1998021756A1 EP 9604947 W EP9604947 W EP 9604947W WO 9821756 A1 WO9821756 A1 WO 9821756A1
Authority
WO
WIPO (PCT)
Prior art keywords
sensor element
floating gate
sensor
field effect
effect transistor
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.)
Ceased
Application number
PCT/EP1996/004947
Other languages
German (de)
French (fr)
Inventor
Amer Aslam
Bedrich Hosticka
Werner Brockherde
Michael Schanz
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.)
Fraunhofer Gesellschaft zur Foerderung der Angewandten Forschung eV
Original Assignee
Fraunhofer Gesellschaft zur Foerderung der Angewandten Forschung eV
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 Fraunhofer Gesellschaft zur Foerderung der Angewandten Forschung eV filed Critical Fraunhofer Gesellschaft zur Foerderung der Angewandten Forschung eV
Priority to EP96939013A priority Critical patent/EP0922304B1/en
Priority to PCT/EP1996/004947 priority patent/WO1998021756A1/en
Priority to DE59608775T priority patent/DE59608775D1/en
Priority to US09/297,925 priority patent/US6141243A/en
Priority to JP52206598A priority patent/JP3269826B2/en
Priority to KR1019997004212A priority patent/KR100319057B1/en
Publication of WO1998021756A1 publication Critical patent/WO1998021756A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/12—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by alteration of electrical resistance
    • G01P15/124—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by alteration of electrical resistance by semiconductor devices comprising at least one PN junction, e.g. transistors
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F30/00—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors
    • H10F30/20—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors
    • H10F30/21—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation
    • H10F30/28—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation the devices being characterised by field-effect operation, e.g. junction field-effect phototransistors
    • H10F30/2823—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation the devices being characterised by field-effect operation, e.g. junction field-effect phototransistors the devices being conductor-insulator-semiconductor devices, e.g. diodes or charge-coupled devices [CCD]
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F30/00—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors
    • H10F30/20—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors
    • H10F30/21—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation
    • H10F30/28—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation the devices being characterised by field-effect operation, e.g. junction field-effect phototransistors
    • H10F30/282—Insulated-gate field-effect transistors [IGFET], e.g. MISFET [metal-insulator-semiconductor field-effect transistor] phototransistors
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F99/00—Subject matter not provided for in other groups of this subclass

Definitions

  • the present invention relates to a monolithically integrated sensor element which has a field effect transistor which is sensitive to a physical variable to be detected and a non-volatile memory.
  • the object of the present invention is to create a space-saving sensor element with associated non-volatile memory, which furthermore does not cause any fluctuations in the parameters due to the manufacture Adaptation problems exist between the sensor and memory cell.
  • the present invention provides a sensor element in the form of a field effect transistor which is sensitive to a physical variable to be detected and whose gate electrode is designed as a floating gate.
  • the gate electrode of the transistor is designed as a floating gate, the same can be used both for setting the operating point of the transistor and for storing a charge which corresponds to a physical variable detected by the field effect transistor.
  • the field effect transistor is connected to a comparator and a programming unit for the EEPROM, which is formed by the floating gate.
  • the non-volatile memory formed by the floating gate of the sensor element according to the invention can be used to set the operating point of the field effect transistor which is sensitive to a physical variable to be detected, to store coefficients for further signal processing or to store the detected signal itself.
  • the field effect transistor which is sensitive to a physical variable to be detected is a photosensitive transistor which is an optical sensor with an integrated, programmable, non-volatile EEPROM memory.
  • the sensor element according to the invention can be implemented in a standard single-poly CMOS / EEPROM technology. Furthermore, the sensor element according to the invention can also be implemented in double-poly CMOS / EEPROM technology, as a result of which the space requirement of the component can be reduced further.
  • the sensor element can be realized using other technologies, as long as the sensor can be adjusted in its operating point at a gate connection.
  • the field effect transistor of the sensor element according to the invention which is sensitive to a physical variable to be detected, can be a CMOS pressure sensor or acceleration sensor whose gate electrode can be moved locally. If a pressure or an acceleration is applied to the transistor, the pressure or the acceleration can be registered by the local displacement of the gate electrode. If the gate electrode of the pressure sensor or the acceleration sensor is designed as a floating gate, a non-volatile memory can be integrated in the sensor.
  • the present invention eliminates the separation of the sensor and the memory chip.
  • the sensor contains a floating gate that can store charges in a non-volatile manner.
  • the charges stored on the floating gate influence the working point of the sensor. This means that it can be stored non-volatile as an analog or digital value. Consequently, the present invention provides a sensor element which contains an analog non-volatile memory in the sensor itself, which can be used for setting the operating point, for example for offset correction, or for signal processing.
  • the realization of the sensor and the memory in a single component saves a lot of chip area compared to the separate implementation according to the prior art, since practically two components are combined in one. There are no additional manufacturing costs because the same manufacturing process can be used. Furthermore, deviations between the sensor and memory cell caused by manufacturing-related local parameter fluctuations are eliminated, since the sensor and the memory cell are integrated in one component. Furthermore, no processing unit is required which processes the sensor signal with the stored value.
  • the processing can be carried out in the according to the sensor element itself. The processing can be carried out, for example, by utilizing the transistor characteristics in the different working areas of the transistor.
  • the non-volatile memory of the sensor can also be used to store the recorded sensor signal. For this purpose, with the help of a control loop, so much charge is transported to the floating gate that the sensor output signal reaches a defined value. The sensor signal is then stored in the sensor as a charge change that is present on the floating gate.
  • FIG. 1 schematically shows the structure of a preferred exemplary embodiment of a sensor element according to the invention
  • FIG. 2 shows the optical characteristics of the sensor element shown in FIG. 1 at different pre-programmed threshold voltages
  • Fig. 3 is a schematic representation of a control loop for storing the sensor signal on the sensor memory.
  • a photo field effect transistor 10 is formed in a substrate 12.
  • the photo field effect transistor is a p-channel MOS transistor, the p + -doped source 14 and the p + - doped drain 16 of which are located in a floating n-well 18.
  • a floating gate 20 over the p-channel of the transistor, which can store charges in a non-volatile manner.
  • the floating gate 20 is designed such that a section thereof is arranged in the p-substrate 12 over n-doped regions.
  • a first n-doped area 22 serves as an injection area, while a second n-doped area 24 serves as a control area.
  • the floating gate 20 and the injection region 22 are arranged opposite one another in such a way that a tunnel region 26 is formed between them.
  • the threshold voltage V- j -h shows an almost logarithmic dependence on the incident light intensity.
  • the threshold voltage V ⁇ is also dependent on any charges present on the floating gate.
  • the threshold voltage V th can be defined, for example, as the gate voltage which causes a drain current of 10 ⁇ A at a drain-source voltage of 2 volts.
  • the threshold voltage can be shifted by charges on the floating gate, a simple non-volatile offset correction or operating point adjustment of the photosensitive sensor is possible.
  • FIG. 2 shows optical characteristics of the sensor element shown in FIG. 1 at different pre-programmed threshold voltages of the sensor transistor. These threshold voltages can be programmed by moving or removing electrons from the control region 24 and the injection region 22 to the floating gate 20 by the application of a high voltage. This is done by a tunnel effect between the injection area 22 and the section of the floating gate 20 arranged above it.
  • the optical characteristics of the sensor are represented logarithmically for voltages V ⁇ o magnitude of 0.75 volts to 1.35 volts, where V ⁇ d ⁇ e ho threshold voltage V ⁇ - ho represents without light irradiation.
  • the programmed threshold voltages do not change the logarithmic dependence of the characteristic curve of the sensor on the incident light intensity.
  • the dashed mark 30 shows the circuit symbol of the photo field effect transistor with integrated EEPROM memory, which represents the sensor element according to the preferred exemplary embodiment of the invention.
  • This sensor element is subjected to light irradiation 32.
  • a supply voltage vdd is present at the source electrode of the transistor.
  • the drain electrode of the transistor is connected to ground via a resistor R.
  • the drain electrode is also connected to a first input of a comparator 34.
  • the second input of the comparator is connected to a voltage source which applies a reference voltage V re f to the same.
  • the output of the comparator is with a programming unit 36 for the EEPROM of the photo field effect transistor.
  • the programming unit 36 is connected to the control area 24 and the injection area 22.
  • the reference voltage V re f corresponds to the output voltage V- when there is no light radiation 32. If the transistor is subjected to light irradiation 32, the threshold voltage of the transistor shifts, which results in a change in the output voltage Vj_. This is detected by the comparator 34, whereupon the programming unit 36 applies charges to the floating gate until the output voltage V ⁇ reaches the reference voltage V re f. If this is the case, it is through the Light irradiation 32 changes the threshold voltage of the PMOS transistor by the charges on the floating gate, which cause a threshold voltage shift. Thus, a voltage corresponding to the light output is stored as a threshold voltage change on the floating gate in the sensor.
  • the present invention thus provides a monolithically integrated sensor element in which manufacturing-related parameter fluctuations or adaptations to changed environmental conditions can be compensated for by a non-volatile memory integrated in the sensor element.
  • the compensation information is stored on the floating gate.
  • the memories according to the invention are well suited as analog memories since they can process the analog signal of the sensor directly or can permanently store an analog operating point voltage to be programmed.
  • the component according to the invention simultaneously contains a sensor element and a non-volatile memory.
  • the sensor element according to the present invention can be used in numerous applications, for example in the field of neural networks with non-volatile mass memories or in the field of learning cameras that can learn image patterns only by “viewing” them.
  • the non-volatile storage option also enables offset and sensitivity correction of the sensor, so that a fixed pattern noise in large photosensor arrays can be eliminated.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Non-Volatile Memory (AREA)
  • Semiconductor Memories (AREA)

Abstract

The invention concerns a sensor element which comprises a field-effect transistor (10) which is sensitive to a physical magnitude to be detected. The gate electrode (20) of the transistor (10) takes the form of a floating gate. In this way, a sensor cell and a non-volatile memory are integrated in the sensor element. The operating point of the transistor can be permanently adjusted by means of the floating gate (20) on which charges can be stored in non-volatile manner. Furthermore, via a simple circuit, charges corresponding to a detected physical magnitude can be stored in non-volatile manner on the floating gate (20).

Description

Sensorelement Sensor element

Beschreibungdescription

Die vorliegende Erfindung bezieht sich auf ein monolithisch-integriertes Sensorelement, das einen gegenüber einer zu erfassenden physikalischen Größe empfindlichen Feldeffekttransistor und einen nicht-flüchtigen Speicher aufweist.The present invention relates to a monolithically integrated sensor element which has a field effect transistor which is sensitive to a physical variable to be detected and a non-volatile memory.

Es ist bekannt, ein Sensorelement und einen nicht-flüchtigen Speicher durch zwei getrennte Bauelemente auf einem Chip zu realisieren. Dabei kann beispielsweise ein MOS-Transistor als Sensor wirken, und ein zweiter MOS-Transistor kann als nicht-flüchtiger Speicher wirken. Bekannte derartige nichtflüchtige Speicher sind EPROMs, Flash-EPROMs , EEPROMs, usw.. EEPROMs werden aufgrund ihrer einfachen Programmierung häufig als nicht-flüchtige digitale Speicher verwendet. Eine analoge Speicherung von Informationen in einer einzelnen EEPROM-Zelle kann die Speicherdichte erhöhen und die Schaltungstechniken für die analoge Signalverarbeitung vereinfachen, wenn eine Langzeitspeicherung notwendig ist.It is known to implement a sensor element and a non-volatile memory using two separate components on one chip. For example, one MOS transistor can act as a sensor, and a second MOS transistor can act as a non-volatile memory. Known such non-volatile memories are EPROMs, flash EPROMs, EEPROMs, etc. Because of their simple programming, EEPROMs are often used as non-volatile digital memories. Analog storage of information in a single EEPROM cell can increase storage density and simplify circuitry for analog signal processing when long term storage is required.

Da bei den genannten Sensorelementen gemäß dem Stand der Technik der eigentliche Sensor und der nicht-flüchtige Speicher durch zwei Transistoren realisiert sind, wird eine große Chipfläche zur Realisierung eines Sensorelements benötigt. Ferner treten durch herstellungsbedingte örtliche Parameterschwankungen Anpassungsprobleme zwischen den beiden Transistoren, die ein Sensorelement bilden, auf, wodurch das Ausgangssignal verändert wird. Desweiteren ist eine Signalverarbeitungseinheit notwendig, die das Sensorsignal und den Speicherinhalt verarbeitet.Since in the aforementioned sensor elements according to the prior art the actual sensor and the non-volatile memory are implemented by two transistors, a large chip area is required to implement a sensor element. Furthermore, due to production-related local parameter fluctuations, adaptation problems occur between the two transistors, which form a sensor element, as a result of which the output signal is changed. Furthermore, a signal processing unit is required which processes the sensor signal and the memory content.

Die Aufgabe der vorliegenden Erfindung besteht darin, ein platzsparendes Sensorelement mit zugehörigem nicht-flüchtigem Speicher zu schaffen, bei dem ferner keine durch herstellungsbedingte örtliche Parameterschwankungen verursachte Anpassungsprobleme zwischen Sensor- und Speicher-Zelle existieren.The object of the present invention is to create a space-saving sensor element with associated non-volatile memory, which furthermore does not cause any fluctuations in the parameters due to the manufacture Adaptation problems exist between the sensor and memory cell.

Diese Aufgabe wird durch ein Sensorelement gemäß Anspruch 1 gelöst.This object is achieved by a sensor element according to claim 1.

Die vorliegende Erfindung schafft ein Sensorelement in der Form eines gegenüber einer zu erfassenden physikalischen Größe empfindlichen Feldeffekttransistors, dessen Gate-Elektrode als Floating-Gate ausgebildet ist. Indem die Gate- Elektrode des Transistors als Floating-Gate ausgebildet ist, kann dieselbe sowohl zur Arbeitspunkteinstellung des Transistors als auch zur Speicherung einer Ladung, die einer durch den Feldeffekttransistor erfaßten physikalischen Größe entspricht, verwendet werden. Dazu ist der Feldeffekttransistor mit einem Komparator und einer Programmiereinheit für den EEPROM, der durch das Floating-Gate gebildet ist, verschaltet.The present invention provides a sensor element in the form of a field effect transistor which is sensitive to a physical variable to be detected and whose gate electrode is designed as a floating gate. In that the gate electrode of the transistor is designed as a floating gate, the same can be used both for setting the operating point of the transistor and for storing a charge which corresponds to a physical variable detected by the field effect transistor. For this purpose, the field effect transistor is connected to a comparator and a programming unit for the EEPROM, which is formed by the floating gate.

Der durch das Floating-Gate des erfindungsgemäßen Sensorelements gebildete nicht-flüchtige Speicher kann zur Einstellung des Arbeitspunktes des gegenüber einer zu erfassenden physikalischen Größe empfindlichen Feldeffekttransistors, zur Abspeicherung von Koeffizienten für die weitere Signalverarbeitung oder zur Abspeicherung des erfaßten Signals selbst verwendet werden. Bei einem bevorzugten Ausführungsbeispiel der vorliegenden Erfindung ist der gegenüber einer zu erfassenden physikalischen Größe empfindliche Feldeffekttransistor ein photoempfindlicher Transistor, der einen optischen Sensor mit einem integrierten, programmierbaren nicht-flüchtigen EEPROM-Speicher darstellt. Das erfindungsgemäße Sensorelement kann in einer Standard-Single-Poly- CMOS/EEPROM-Technologie realisiert sein. Ferner kann das erfindungsgemäße Sensorelement ebenso in der Double-Poly- CMOS/EEPROM-Technologie realisiert werden, wodurch der Platzbedarf des Bauelements weiter verringert werden kann.The non-volatile memory formed by the floating gate of the sensor element according to the invention can be used to set the operating point of the field effect transistor which is sensitive to a physical variable to be detected, to store coefficients for further signal processing or to store the detected signal itself. In a preferred exemplary embodiment of the present invention, the field effect transistor which is sensitive to a physical variable to be detected is a photosensitive transistor which is an optical sensor with an integrated, programmable, non-volatile EEPROM memory. The sensor element according to the invention can be implemented in a standard single-poly CMOS / EEPROM technology. Furthermore, the sensor element according to the invention can also be implemented in double-poly CMOS / EEPROM technology, as a result of which the space requirement of the component can be reduced further.

Neben der CMOS-Technologie kann das erfindungsgemäße Sensor- element unter Verwendung weiterer Technologien realisiert werden, solange der Sensor an einem Gate-Anschluß in seinem Arbeitspunkt verstellt werden kann. Beispielsweise kann der gegenüber einer zu erfassenden physikalischen Größe empfindliche Feldeffekttransistor des erfindungsgemäßen Sensorelements ein CMOS-Drucksensor oder -Beschleunigungssensor sein, dessen Gate-Elektrode örtlich verschiebbar ist. Wird der Transistor mit einem Druck oder einer Beschleunigung beaufschlagt, kann der Druck oder die Beschleunigung durch die örtliche Verschiebung der Gate-Elektrode registriert werden. Wird bei dem Drucksensor oder dem Beschleunigungssensor die Gate-Elektrode als Floating-Gate ausgeführt, läßt sich ein nicht-flüchtiger Speicher in dem Sensor integrieren.In addition to CMOS technology, the sensor element can be realized using other technologies, as long as the sensor can be adjusted in its operating point at a gate connection. For example, the field effect transistor of the sensor element according to the invention, which is sensitive to a physical variable to be detected, can be a CMOS pressure sensor or acceleration sensor whose gate electrode can be moved locally. If a pressure or an acceleration is applied to the transistor, the pressure or the acceleration can be registered by the local displacement of the gate electrode. If the gate electrode of the pressure sensor or the acceleration sensor is designed as a floating gate, a non-volatile memory can be integrated in the sensor.

Durch die vorliegende Erfindung wird die Trennung des Sensors und des Speicherbausteins aufgehoben. Der Sensor enthält ein Floating-Gate, das Ladungen nicht-flüchtig speichern kann. Die auf dem Floating-Gate gespeicherten Ladungen beeinflussen den Arbeitspunkt des Sensors. Somit kann dieser als analoger oder digitaler Wert nicht-flüchtig gespeichert werden. Folglich erhält man mit der vorliegenden Erfindung ein Sensorelement, das einen analogen nicht-flüchtigen Speicher in dem Sensor selbst beinhaltet, welcher zur Arbeitspunkteinstellung, beispielsweise zur Offset-Korrektur, oder auch zur Signalverarbeitung benutzt werden kann.The present invention eliminates the separation of the sensor and the memory chip. The sensor contains a floating gate that can store charges in a non-volatile manner. The charges stored on the floating gate influence the working point of the sensor. This means that it can be stored non-volatile as an analog or digital value. Consequently, the present invention provides a sensor element which contains an analog non-volatile memory in the sensor itself, which can be used for setting the operating point, for example for offset correction, or for signal processing.

Die Realisierung des Sensors und des Speichers in einem einzelnen Bauelement erspart sehr viel Chipfläche gegenüber der getrennten Realisierung gemäß dem Stand der Technik, da praktisch zwei Bauelemente in einem zusammengefaßt sind. Zusätzliche Fertigungskosten fallen nicht an, da derselbe Herstellungsprozeß verwendet werden kann. Ferner werden durch herstellungsbedingte örtliche Parameterschwankungen verursachte Abweichungen zwischen Sensor- und Speicherzelle eliminiert, da die Sensor- und die Speicherzelle in einem Bauelement integriert sind. Ferner ist keine Verarbeitungseinheit notwendig, die das Sensorsignal mit dem gespeicherten Wert verarbeitet. Die Verarbeitung kann in dem erfindungsge- mäßen Sensorelement selbst geschehen. Die Verarbeitung kann beispielsweise durch die Ausnutzung der Transistorkennlinien in den unterschiedlichen Arbeitsbereichen des Transistors durchgeführt werden.The realization of the sensor and the memory in a single component saves a lot of chip area compared to the separate implementation according to the prior art, since practically two components are combined in one. There are no additional manufacturing costs because the same manufacturing process can be used. Furthermore, deviations between the sensor and memory cell caused by manufacturing-related local parameter fluctuations are eliminated, since the sensor and the memory cell are integrated in one component. Furthermore, no processing unit is required which processes the sensor signal with the stored value. The processing can be carried out in the according to the sensor element itself. The processing can be carried out, for example, by utilizing the transistor characteristics in the different working areas of the transistor.

Der nicht-flüchtige Speicher des Sensors kann ferner dazu verwendet werden, um das aufgenommene Sensorsignal zu speichern. Dazu wird mit Hilfe einer Regelschleife so viel Ladung auf das Floating-Gate transportiert, daß das Ausgangssignal des Sensors einen definierten Wert erreicht. Das Sensorsignal ist dann als eine Ladungsänderung, die auf dem Floating-Gate vorliegt, in dem Sensor gespeichert.The non-volatile memory of the sensor can also be used to store the recorded sensor signal. For this purpose, with the help of a control loop, so much charge is transported to the floating gate that the sensor output signal reaches a defined value. The sensor signal is then stored in the sensor as a charge change that is present on the floating gate.

Bevorzugte Ausführungsbeispiele der vorliegenden Erfindung werden nachfolgend bezugnehmend auf die beiliegenden Zeichnungen näher erläutert. Es zeigen:Preferred exemplary embodiments of the present invention are explained in more detail below with reference to the accompanying drawings. Show it:

Fig. 1 schematisch den Aufbau eines bevorzugten Ausfüh- rungsbeispiels eines erfindungsgemäßen Sensorelements ;1 schematically shows the structure of a preferred exemplary embodiment of a sensor element according to the invention;

Fig. 2 eine Darstellung der optischen Kennlinien des in Fig. 1 dargestellten Sensorelements bei verschiedenen vorprogrammierten Schwellenspannungen; undFIG. 2 shows the optical characteristics of the sensor element shown in FIG. 1 at different pre-programmed threshold voltages; and

Fig. 3 eine schematische Darstellung einer Regelschleife zur Abspeicherung des Sensorsignals auf dem Sensorspeicher.Fig. 3 is a schematic representation of a control loop for storing the sensor signal on the sensor memory.

Anhand von Fig. 1, die ein bevorzugtes Ausführungsbeispiel der vorliegenden Erfindung in der Form eines photoempfindlichen Sensorelements darstellt, wird nachfolgend die vorliegende Erfindung näher erläutert.1, which represents a preferred exemplary embodiment of the present invention in the form of a photosensitive sensor element, the present invention is explained in more detail below.

Ein Photo-Feldeffekttransistor 10 ist in einem Substrat 12 gebildet. Der Photo-Feldeffekttransistor ist ein p-Kanal- MOS-Transistor, dessen p+-dotierte Source 14 und dessen p+- dotiertes Drain 16 in einer floatenden n-Wanne 18 liegen. Über dem p-Kanal des Transistors liegt anstelle des üblichen Gates ein Floating-Gate 20, das Ladungen nicht-flüchtig speichern kann. Das Floating-Gate 20 ist derart ausgebildet, daß ein Abschnitt desselben über n-dotierten Bereichen in dem p-Substrat 12 angeordnet ist. Ein erster n-dotierter Bereich 22 dient als Injektionsbereich, während ein zweiter n-dotierter Bereich 24 als Steuerbereich dient. Das Floating-Gate 20 und der Injektionsbereich 22 sind einander gegenüberliegend derart angeordnet, daß zwischen denselben eine Tunnelregion 26 gebildet ist.A photo field effect transistor 10 is formed in a substrate 12. The photo field effect transistor is a p-channel MOS transistor, the p + -doped source 14 and the p + - doped drain 16 of which are located in a floating n-well 18. Instead of the usual gate, there is a floating gate 20 over the p-channel of the transistor, which can store charges in a non-volatile manner. The floating gate 20 is designed such that a section thereof is arranged in the p-substrate 12 over n-doped regions. A first n-doped area 22 serves as an injection area, while a second n-doped area 24 serves as a control area. The floating gate 20 and the injection region 22 are arranged opposite one another in such a way that a tunnel region 26 is formed between them.

Treffen nun Lichtwellen auf das Sensorelement auf, bewirkt der Photoeffekt, daß sich Elektronen in der n-Wanne des Transistors 10 ansammeln, wodurch die Schwellenspannung des PMOS-Transistors verschoben wird. Die Schwellenspannung V-j-h zeigt eine nahezu logarithmische Abhängigkeit von der einfallenden Lichtintensität. Die Schwellenspannung V^ ist ferner von eventuell auf dem Floating-Gate vorliegenden Ladungen abhängig. Die Schwellenspannung Vth kann beispielsweise als die Gate-Spannung definiert werden, die einen Drainstrom von 10 μA bei einer Drain-Source-Spannung von 2 Volt bewirkt.If light waves now strike the sensor element, the photo effect causes electrons to accumulate in the n-well of the transistor 10, as a result of which the threshold voltage of the PMOS transistor is shifted. The threshold voltage V- j -h shows an almost logarithmic dependence on the incident light intensity. The threshold voltage V ^ is also dependent on any charges present on the floating gate. The threshold voltage V th can be defined, for example, as the gate voltage which causes a drain current of 10 μA at a drain-source voltage of 2 volts.

Dadurch, daß die Schwellenspannung durch auf dem Floating- Gate befindliche Ladungen verschoben werden kann, ist eine einfache nicht-flüchtige Offset-Korrektur oder Arbeitspunkteinstellung des photoempfindlichen Sensors möglich.Because the threshold voltage can be shifted by charges on the floating gate, a simple non-volatile offset correction or operating point adjustment of the photosensitive sensor is possible.

In Fig. 2 sind optische Kennlinien des in Fig. 1 dargestellten Sensorelements bei verschiedenen vorprogrammierten Schwellenspannungen des Sensor-Transistors dargestellt. Diese Schwellenspannungen können programmiert werden, indem Elektronen durch das Anlegen einer Hochspannung zwischen dem Steuerbereich 24 und dem Injektionsbereich 22 zu dem Floating-Gate 20 bewegt oder von demselben entfernt werden. Dies geschieht durch einen Tunneleffekt zwischen dem Injektionsbereich 22 und dem über demselben angeordneten Abschnitt des Floating-Gates 20. In Fig. 2 sind die optischen Kennlinien des Sensors logarithmisch für Spannungen V^o betragsmäßig von 0,75 Volt bis 1,35 Volt dargestellt, wobei V^ho d^e Schwellenspannung V^-ho ohne Lichteinstrahlung darstellt. Wie in Fig. 2 zu erkennen ist, verändern die programmierten Schwellenspannungen die logarithmische Abhängigkeit der Kennlinie des Sensors von der einfallenden Lichtintensität nicht.FIG. 2 shows optical characteristics of the sensor element shown in FIG. 1 at different pre-programmed threshold voltages of the sensor transistor. These threshold voltages can be programmed by moving or removing electrons from the control region 24 and the injection region 22 to the floating gate 20 by the application of a high voltage. This is done by a tunnel effect between the injection area 22 and the section of the floating gate 20 arranged above it. In FIG. 2, the optical characteristics of the sensor are represented logarithmically for voltages V ^ o magnitude of 0.75 volts to 1.35 volts, where V ^ d ^ e ho threshold voltage V ^ - ho represents without light irradiation. As can be seen in FIG. 2, the programmed threshold voltages do not change the logarithmic dependence of the characteristic curve of the sensor on the incident light intensity.

In Fig. 3 ist eine Regelschleife dargestellt, die es auf eine einfache Art und Weise ermöglicht, eine einem optischen Signal entsprechende Ladung auf dem Floating-Gate zu speichern. In der gestrichelten Markierung 30 ist das Schaltzeichen des Photo-Feldeffekttransistors mit integriertem EEPROM-Speicher, der das Sensorelement gemäß dem bevorzugten Ausführungsbeispiel der Erfindung darstellt, gezeigt. Dieses Sensorelement wird mit einer Lichtbestrahlung 32 beaufschlagt. An der Source-Elektrode des Transistors liegt eine Versorgungsspannung vdd. Die Drain-Elektrode des Transistors ist über einen Widerstand R mit Masse verbunden. Die Drain-Elektrode ist ferner mit einem ersten Eingang eines Komparators 34 verbunden. Der zweite Eingang des Komparators ist mit einer Spannungsquelle verbunden, die eine Referenzspannung Vref an denselben anlegt. Der Ausgang des Komparators ist mit einer Programmiereinheit 36 für den EEPROM des Photo-Feldeffekttransistors. Die Programmiereinheit 36 ist mit dem Steuerbereich 24 und dem Injektionsbereich 22 verbunden.3 shows a control loop which makes it possible in a simple manner to store a charge corresponding to an optical signal on the floating gate. The dashed mark 30 shows the circuit symbol of the photo field effect transistor with integrated EEPROM memory, which represents the sensor element according to the preferred exemplary embodiment of the invention. This sensor element is subjected to light irradiation 32. A supply voltage vdd is present at the source electrode of the transistor. The drain electrode of the transistor is connected to ground via a resistor R. The drain electrode is also connected to a first input of a comparator 34. The second input of the comparator is connected to a voltage source which applies a reference voltage V re f to the same. The output of the comparator is with a programming unit 36 for the EEPROM of the photo field effect transistor. The programming unit 36 is connected to the control area 24 and the injection area 22.

Die Referenzspannung Vref entspricht der Ausgangsspannung V-, wenn keine Lichteinstrahlung 32 vorliegt. Wird der Transistor mit einer Lichteinstrahlung 32 beaufschlagt, verschiebt sich die Schwellenspannung des Transistors, was eine Änderung der Ausgangsspannung Vj_ zur Folge hat. Dies wird durch den Komparator 34 erfaßt, woraufhin durch die Programmiereinheit 36 solange Ladungen auf das Floating-Gate aufgebracht werden, bis die Ausgangsspannung V^ die Referenzspannung Vref erreicht. Ist dies der Fall, ist die durch die Lichteinstrahlung 32 veränderte Schwellenspannung des PMOS- Transistors durch die Ladungen auf dem Floating-Gate, die eine Schwellenspannungsverschiebung bewirken, kompensiert. Somit ist eine der Lichtleistung entsprechende Spannung als Schwellenspannungsänderung auf dem Floating-Gate in dem Sensor gespeichert.The reference voltage V re f corresponds to the output voltage V- when there is no light radiation 32. If the transistor is subjected to light irradiation 32, the threshold voltage of the transistor shifts, which results in a change in the output voltage Vj_. This is detected by the comparator 34, whereupon the programming unit 36 applies charges to the floating gate until the output voltage V ^ reaches the reference voltage V re f. If this is the case, it is through the Light irradiation 32 changes the threshold voltage of the PMOS transistor by the charges on the floating gate, which cause a threshold voltage shift. Thus, a voltage corresponding to the light output is stored as a threshold voltage change on the floating gate in the sensor.

Die vorliegende Erfindung liefert somit ein monolithisch-integriertes Sensorelement, bei dem herstellungsbedingte Parameterschwankungen oder auch Anpassungen an veränderte Umweltbedingungen durch einen in dem Sensorelement integrierten nicht-flüchtigen Speicher kompensiert werden können. Die Kompensationsinformationen werden dabei auf das Floating- Gate gespeichert. Ferner eignen sich die erfindungsgemäßen Speicher gut als Analogspeicher, da dieselben das analoge Signal des Sensors direkt verarbeiten können oder eine zu programmierende analoge Arbeitspunktspannung dauerhaft speichern können. Das erfindungsgemäße Bauelement enthält gleichzeitig ein Sensorelement und einen nicht-flüchtigen Speicher.The present invention thus provides a monolithically integrated sensor element in which manufacturing-related parameter fluctuations or adaptations to changed environmental conditions can be compensated for by a non-volatile memory integrated in the sensor element. The compensation information is stored on the floating gate. Furthermore, the memories according to the invention are well suited as analog memories since they can process the analog signal of the sensor directly or can permanently store an analog operating point voltage to be programmed. The component according to the invention simultaneously contains a sensor element and a non-volatile memory.

Das Sensorelement gemäß der vorliegenden Erfindung kann in zahlreichen Anwendungen, beispielsweise auf dem Gebiet von neuronalen Netzwerken mit nicht-flüchtigen Massenspeichern oder auf dem Gebiet von Lernkameras, die Bildmuster nur durch ein "Betrachten" lernen können, verwendet werden. Die nicht-flüchtige Speicherungsmöglichkeit ermöglicht ferner eine Versatz- und Empfindlichkeits-Korrektur des Sensors, so daß ein festes Musterrauschen in großen Photosensorarrays beseitigt werden kann. The sensor element according to the present invention can be used in numerous applications, for example in the field of neural networks with non-volatile mass memories or in the field of learning cameras that can learn image patterns only by “viewing” them. The non-volatile storage option also enables offset and sensitivity correction of the sensor, so that a fixed pattern noise in large photosensor arrays can be eliminated.

Claims

Patentansprüche claims 1. Sensorelement in der Form eines gegenüber einer zu erfassenden physikalischen Größe empfindlichen Feldeffekttransistors (10) , dadurch gekennzeichnet, daß die Gate- Elektrode (20) des Transistors (10) als Floating-Gate ausgebildet ist.1. Sensor element in the form of a field effect transistor (10) sensitive to a physical quantity to be detected, characterized in that the gate electrode (20) of the transistor (10) is designed as a floating gate. 2. Sensorelement gemäß Anspruch 1, dadurch gekennzeichnet, daß der Feldeffekttransistor (10) ein photoempfindlicher Feldeffekttransistor ist.2. Sensor element according to claim 1, characterized in that the field effect transistor (10) is a photosensitive field effect transistor. 3. Sensorelement gemäß Anspruch 1, dadurch gekennzeichnet, daß der Feldeffekttransistor ein Druck- oder Beschleuni- gungs-empfindlicher Sensor mit einem örtlich verschiebbaren Floating-Gate ist.3. Sensor element according to claim 1, characterized in that the field effect transistor is a pressure or acceleration sensitive sensor with a locally displaceable floating gate. 4. Sensorelement gemäß einem der Ansprüche 1 bis 3 , dadurch gekennzeichnet, daß das Floating-Gate (20) über einen Tunneleffekt mit Ladungen beaufschlagbar ist.4. Sensor element according to one of claims 1 to 3, characterized in that the floating gate (20) can be charged with charges via a tunnel effect. 5. Sensorelement gemäß Anspruch 4, dadurch gekennzeichnet, daß der Feldeffekttransistor (10) in einem Substrat (12) ausgebildet ist, und daß das Floating-Gate (20) derart ausgebildet ist, daß ein Abschnitt des Floating-Gates einem in dem Substrat (12) angeordneten hochdotierten Bereich (22) gegenüberliegt, derart, daß zwischen dem hochdotierten Bereich (22) und dem Abschnitt des Floating-Gate (20) eine Tunnelregion gebildet ist.5. Sensor element according to claim 4, characterized in that the field effect transistor (10) is formed in a substrate (12), and that the floating gate (20) is designed such that a portion of the floating gate one in the substrate ( 12) arranged highly doped region (22), such that a tunnel region is formed between the highly doped region (22) and the section of the floating gate (20). 6. Sensorelement gemäß einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß das Floating-Gate mit einer Programmiereinheit (36) koppelbar ist, mittels der Ladungen auf das Floating-Gate (20) bringbar und von demselben entfernbar sind.6. Sensor element according to one of claims 1 to 5, characterized in that the floating gate can be coupled to a programming unit (36), by means of the charges on the floating gate (20) can be brought and removed from the same. 7. Sensorelement gemäß Anspruch 6, dadurch gekennzeichnet, daß die Source-Elektrode (16) des Feldeffekttransistors (10) mit einer Spannungsquelle (vdd) verbunden ist und die Drain-Elektrode (14) des Feldeffekttransistors (10) über einen Widerstand (R) mit Masse und ferner direkt mit einem ersten Eingang eines Komparators (34) verbunden ist, wobei ein zweiter Eingang des Komparators (34) mit einer Referenzspannungsquelle (Vref) und der Ausgang des Komparators (34) mit der Programmiereinheit (36) verbunden ist.7. Sensor element according to claim 6, characterized in that that the source electrode (16) of the field effect transistor (10) is connected to a voltage source (vdd) and the drain electrode (14) of the field effect transistor (10) via a resistor (R) to ground and also directly to a first input of a Comparator (34) is connected, a second input of the comparator (34) being connected to a reference voltage source (V re f) and the output of the comparator (34) being connected to the programming unit (36). 8. Verfahren zum Speichern einer einer zu erfassenden physikalischen Größe entsprechenden Ladung auf dem Sensorelement gemäß Anspruch 7, gekennzeichnet durch folgende Schritte:8. A method for storing a charge corresponding to a physical quantity to be detected on the sensor element according to claim 7, characterized by the following steps: Beaufschlagen des Sensorelements mit der zu erfassenden physikalischen Größe (32) ; undLoading the sensor element with the physical variable (32) to be detected; and Aufbringen von Ladungen auf das Floating-Gate (20) mittels der Programmiereinheit (36) , bis die am ersten Eingang des Komparators (34) anliegende Spannung (Vj der am zweiten Eingang des Komparators anliegenden Referenzspannung (Vref) entspricht. Applying charges to the floating gate (20) by means of the programming unit (36) until the voltage (V j ) at the first input of the comparator (34) corresponds to the reference voltage (V re f) at the second input of the comparator.
PCT/EP1996/004947 1996-11-12 1996-11-12 Sensor element Ceased WO1998021756A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
EP96939013A EP0922304B1 (en) 1996-11-12 1996-11-12 Sensor element
PCT/EP1996/004947 WO1998021756A1 (en) 1996-11-12 1996-11-12 Sensor element
DE59608775T DE59608775D1 (en) 1996-11-12 1996-11-12 SENSOR ELEMENT
US09/297,925 US6141243A (en) 1996-11-12 1996-11-12 Sensor element
JP52206598A JP3269826B2 (en) 1996-11-12 1996-11-12 Sensor element
KR1019997004212A KR100319057B1 (en) 1996-11-12 1996-11-12 Sensor element

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP1996/004947 WO1998021756A1 (en) 1996-11-12 1996-11-12 Sensor element

Publications (1)

Publication Number Publication Date
WO1998021756A1 true WO1998021756A1 (en) 1998-05-22

Family

ID=8166396

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1996/004947 Ceased WO1998021756A1 (en) 1996-11-12 1996-11-12 Sensor element

Country Status (4)

Country Link
JP (1) JP3269826B2 (en)
KR (1) KR100319057B1 (en)
DE (1) DE59608775D1 (en)
WO (1) WO1998021756A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0990911A1 (en) * 1998-09-29 2000-04-05 Siemens Aktiengesellschaft Micromechanical sensor based on the field effect and the use thereof
US7180798B2 (en) 2001-04-12 2007-02-20 Fuji Electric Co., Ltd. Semiconductor physical quantity sensing device
DE10216016B4 (en) * 2001-04-12 2010-07-08 Fuji Electric Systems Co., Ltd. Semiconductor device for measuring a physical quantity
EP2466317A1 (en) * 2010-12-17 2012-06-20 Nxp B.V. Acceleration Threshold Detection

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102320950B1 (en) * 2020-02-13 2021-11-02 연세대학교 산학협력단 Pressure sensing memory transistor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4788581A (en) * 1984-04-10 1988-11-29 Hahn-Meitner-Institut Berlin Gmbh MOS dosimeter
DE4004179A1 (en) * 1990-02-12 1991-08-14 Fraunhofer Ges Forschung INTEGRATABLE, CAPACITIVE PRESSURE SENSOR AND METHOD FOR PRODUCING THE SAME
US5343064A (en) * 1988-03-18 1994-08-30 Spangler Leland J Fully integrated single-crystal silicon-on-insulator process, sensors and circuits
JPH07115182A (en) * 1993-10-15 1995-05-02 Matsushita Electric Ind Co Ltd Photoelectric conversion element with memory function and solid-state imaging device
US5541878A (en) * 1991-05-09 1996-07-30 Synaptics, Incorporated Writable analog reference voltage storage device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4788581A (en) * 1984-04-10 1988-11-29 Hahn-Meitner-Institut Berlin Gmbh MOS dosimeter
US5343064A (en) * 1988-03-18 1994-08-30 Spangler Leland J Fully integrated single-crystal silicon-on-insulator process, sensors and circuits
DE4004179A1 (en) * 1990-02-12 1991-08-14 Fraunhofer Ges Forschung INTEGRATABLE, CAPACITIVE PRESSURE SENSOR AND METHOD FOR PRODUCING THE SAME
US5541878A (en) * 1991-05-09 1996-07-30 Synaptics, Incorporated Writable analog reference voltage storage device
JPH07115182A (en) * 1993-10-15 1995-05-02 Matsushita Electric Ind Co Ltd Photoelectric conversion element with memory function and solid-state imaging device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 095, no. 008 29 September 1995 (1995-09-29) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0990911A1 (en) * 1998-09-29 2000-04-05 Siemens Aktiengesellschaft Micromechanical sensor based on the field effect and the use thereof
US7180798B2 (en) 2001-04-12 2007-02-20 Fuji Electric Co., Ltd. Semiconductor physical quantity sensing device
DE10216016B4 (en) * 2001-04-12 2010-07-08 Fuji Electric Systems Co., Ltd. Semiconductor device for measuring a physical quantity
EP2466317A1 (en) * 2010-12-17 2012-06-20 Nxp B.V. Acceleration Threshold Detection

Also Published As

Publication number Publication date
JP3269826B2 (en) 2002-04-02
JP2000515981A (en) 2000-11-28
KR100319057B1 (en) 2001-12-29
KR20000053235A (en) 2000-08-25
DE59608775D1 (en) 2002-03-28

Similar Documents

Publication Publication Date Title
DE3533922C2 (en) Solid-state image sensing device
DE60220590T2 (en) Method for reducing coupling effects between multi-level memory elements of a non-volatile memory
DE69230346T2 (en) Constant voltage circuit
DE69521710T2 (en) MEASURING THE POLARIZATION STATE OF A MEMORY BY APPLYING A VARIABLE VOLTAGE TO A GATE
DE69810270T2 (en) DIFFERENTIAL FLASH STORAGE CELL AND OPERATING METHOD THEREFOR
DE4343722C2 (en) Precision reference voltage circuit suitable for use in computer systems
DE69610062T2 (en) Non-volatile PMOS memory device with a single polysilicon layer
DE10002266B4 (en) Nonvolatile semiconductor memory device and programming method therefor
DE602004012122T2 (en) NON-VOLATILE MEMORY AND METHOD WITH DEFINITIVE BIT CONTROL COMPENSATION DEPENDING ON NEIGHBORING OPERATING TYPES
DE69900372T2 (en) Supply voltage switch
DE60202077T2 (en) VOLTAGE INCREASING CIRCUIT WITH DETERMINATION OF THE SUPPLY VOLTAGE FOR COMPENSATION OF VARIATIONS OF THE SUPPLY VOLTAGE WHEN READING
DE69229995T2 (en) Voltage regulator for storage devices
DE3851479T2 (en) Memory cell of a non-volatile semiconductor memory device.
DE4232025C2 (en) Electrically erasable and programmable non-volatile semiconductor memory with automatic write check controller
DE69122537T2 (en) EEPROM with threshold measurement circuit
DE69604929T2 (en) FLASH EEPROM MEMORY WITH SEPARATE REFERENCE MATIX
DE68918880T2 (en) Electrically erasable non-volatile semiconductor memory device.
DE69625755T2 (en) Non-volatile two-transistor memory cell with a single polysilicon gate
DE69016153T2 (en) Non-volatile semiconductor memory device.
DE4035660A1 (en) ELECTRICALLY PROGRAMMABLE STORAGE DEVICE AND METHOD FOR ACCESSING / PROGRAMMING STORAGE CELLS
DE69614787T2 (en) MEMORY MATRIX WITH MULTI-STATE MEMORY CELLS
DE69434695T2 (en) Method for producing a semiconductor device
DE69628056T2 (en) Semiconductor memory device and method for control
DE69432846T2 (en) Semiconductor memory device
DE69909930T2 (en) Methods for erasing and programming memory arrays

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP KR US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1996939013

Country of ref document: EP

ENP Entry into the national phase

Ref country code: JP

Ref document number: 1998 522065

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 09297925

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: 1019997004212

Country of ref document: KR

NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1998522065

Format of ref document f/p: F

WWP Wipo information: published in national office

Ref document number: 1996939013

Country of ref document: EP

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWP Wipo information: published in national office

Ref document number: 1019997004212

Country of ref document: KR

WWG Wipo information: grant in national office

Ref document number: 1019997004212

Country of ref document: KR

WWG Wipo information: grant in national office

Ref document number: 1996939013

Country of ref document: EP