JPH0816922B2 - Identification card with integrated circuit for electrical signal processing - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention comprises an integrated circuit integrated on a substrate, which provides energy transfer, data output and, if required, data input to operate a circuit unit for storing specific information. The present invention relates to an identification card having a circuit unit for storing specific information for controlling a conversion element for performing.

[0002]

2. Description of the Related Art Today, a large number of circuit units in the form of integrated circuits are each formed on one semiconductor chip (substrate). These semiconductor chips have metal terminals on their edges, and by suitable welding or brazing methods the semiconductor chips are connected through leads to the terminals of the housing that surrounds the semiconductor chip, or directly to the peripheral circuit. It is connected.

Although there are various application examples, in those application examples, the electrical connection between the semiconductor chip and its peripheral circuits does not satisfy the required conditions. For example, by providing an identification card on the semiconductor chip to improve protection against imitation, at the same time storing a large amount of information in the identification card and possibly changing this information in the control device in cooperation with the transmitter and receiver It has been proposed to do so (West German Laid-Open Publication No. 2659573).

It is said that housing the circuit unit in the identification card may damage the electrical connection between the circuit unit and the terminals provided on the card in particular because the card is mechanically stressed during use. There is a problem. Also, housing the circuit unit in the identification card is complicated by the terminal wires which are sensitively affected by mechanical stress.

Therefore, it has been proposed to provide a connecting element for directly inputting / outputting data to / from a semiconductor chip without using a lead wire (West German Patent Application Publication No. 1945777).
No.), the connecting element is provided, for example, in a so-called “identification object” for identifying a person. The data is transmitted through a bundle of optical fibers which must be arranged in the circuit unit in coordination with the conversion elements. Energy is transmitted as a capacitance change through the corresponding metal surface applied to the outside of the identification object. Since the surface is connected to the semiconductor chip by the lead wire, the same problem as described above occurs.

In the conventional identification card (see Japanese Patent Laid-Open No. 51-15946 (Fig. 1) and Japanese Patent Laid-Open No. 51-159467 (Fig. 1)), data input and data output are optical. / Electric (or electric / optical) conversion element, and further, energy supply is performed by the primary coil (151) on the transmitter / receiver side and the secondary coil (105) of the identification card, and direct current is supplied. (Filter 107). Further, in another conventional transmitter / receiver (see Japanese Patent Laid-Open No. 55-4199 (FIG. 1)), an optical transmission line (200) for transmitting an optical signal having two components, is converted into electric energy. Direct current component for supplying direct current to electric part, information component having information to be transmitted, detector for converting optical signal into electric signal (3
02), a filter (30) for separating information and energy
3) is provided.

[0007]

However, the above-mentioned identification card (JP-A-51-15946 and JP-A-51-15947) and a transmitter / receiver (JP-A-55).
No. 4199 gazette) has not been solved. In other words, problems such as that the light / converting element is large and difficult to manufacture, and that the identification card contains a mixture of DC component light for energy supply and AC component light for information transmission have not been solved.

Therefore, it is an object of the present invention to provide an identification card which is small in size and easy to manufacture, and which is capable of separating DC component light and AC component light.

[0009]

According to the present invention, an integrated circuit for electrical signal processing monolithically integrated on a semiconductor substrate, an optical / electrical conversion element for data input, an electrical / optical conversion element for data output, Light for power supply to integrated circuits /
An identification card having an electrical conversion element, wherein the data input optical / electrical conversion element and the power supply optical / electrical conversion element are monolithically integrated on the semiconductor substrate as a common element, and the integrated circuit receives the data. An identification card provided with an electric filter capable of separating an AC component that can be processed as optical information and a DC component for power supply.

[0010]

Therefore, the substrate not only operates as an integrated circuit, but also as a data conversion and energy supply element directly connected to the substrate. The circuit unit is a small unit that can be inserted into an arbitrary identification element such as an identification card, a coin, or a ring by a simple method. Since there is no lead wire, the circuit unit can be operated reliably without causing a failure. Finally, the compact design offers the possibility of further miniaturizing such circuit units, thus making it possible to adapt the circuit units heretofore known as previously inapplicable in various cases.

There are various methods for realizing the conversion means according to the technical idea of the present invention. A light converter, such as a photocell, can be provided for energy transfer integrated on the substrate, which provides the necessary electricity to the circuit when illuminated by light. Further, data input / output is performed optically, whereby a liquid crystal element is used as a data output, and a photodiode or the like is used as a light sensitive element corresponding to the output for data input.

In all embodiments, it is extremely important that the conversion element is in direct contact with the substrate without leads.

[0013]

1 (A) and 1 (B) show a circuit unit 15 according to the invention as a schematic and enlarged, simple embodiment. The circuit unit can be, for example, a circuit unit which is energized by a photoelectric transducer and which has elements from which certain information can be read during operation. When this circuit unit is incorporated in an identification card, this circuit unit can be used, for example, to store a codeword (password), whereby the identification card controls an electronic key which controls the admission to a place. Etc. can be used.

As shown in FIG. 1B, an integrated circuit 2 formed by a conventional method is provided on a silicon wafer (silicon substrate) 1. The integrated circuit 2 is provided only on a part of the wafer 1. A photo-sensitive semiconductor, for example, a photo cell 3 is integrated on the remainder of the wafer surface, and the photo cell supplies energy required for the operation of the integrated circuit, which energy is incident by a method known in the related art. It is generated depending on the radiated power of light. The above-mentioned elements are connected to each other and to the integrated circuit by the conductive raised strips, and the conductive raised linear bodies (wirings) are vapor-deposited on the wafer 1 by the usual process of manufacturing integrated circuits.

The data is read by the so-called liquid crystal element 4, which is often used today as a display element. The liquid crystal element is provided with a liquid crystal film 5, and the liquid crystal film 5 is encapsulated in a frame 8 provided between two transparent electrodes 6 and 7 in the frame 8. The frame 8 is adapted to the dimensions of the silicon wafer 1. As is known, a liquid crystal film has the property that when an electric field is applied to the conductive coatings 6 and 7 on both sides of the film, it changes to a transparent state by consuming very little energy. ing. Therefore, the illuminated liquid crystal film sometimes looks milky white to the observer, while it is transparent in the excited state, and whatever the background is (dark film 1 in FIG. 1B).
0), the background becomes visible. To complete the circuit unit, the frame 8 containing the liquid crystal is fixedly connected to the silicon wafer 1, for example by means of a suitable adhesive, and the electrodes 6 and 7 are connected to the corresponding terminals of the integrated circuit 2 by the through-contact method. Frame 8 is transparent in the spectral range for photocell 3, so that covering photocell 3 with frame 8 does not interfere with the function of photocell 3. Especially when the liquid crystal element is used for data display, the circuit configuration of the data display element 4 and the energy supply element 3 is such that the photocell is activated when the circuit element is illuminated over a large surface, and the liquid crystal display Has the benefit of being lit. The operation of the circuit unit is therefore possible without any elaborate positioning problems and without great effort (only one lighting unit).

The energy supply and data display elements need not be provided on only one side of the silicon wafer. FIG. 2A shows the circuit unit 15 incorporated in the identification card 16. As already mentioned above, the circuit unit in the above exemplary embodiment, in its simplest form, responds to only one defined information in one control process, for example in the form of ID mathematics. The number is stored in the memory that permanently stores the number in the circuit unit during the manufacturing process of the circuit unit according to the conventionally known method.
As shown in FIG. 2B, the identification card is oriented during the identification number test, in particular under the device 17 with the light source 18 illuminating the circuit unit 15. By this irradiation, the photocell 3 supplies the energy necessary for the operation of the circuit unit. When the circuit becomes operational, the information stored by the liquid crystal element 4 shown in FIG. 1B is displayed as a light / dark change, and the liquid crystal element 4 is also illuminated by the light source.
The liquid crystal element is detected on the photodiode 23 by an optical system comprising a diaphragm 20 and two lenses 21 and 22 in a light / dark modulation format. Adjustment of the identification card within the controller can be performed by a suitable mechanical positioning tool (not shown).

The circuit units shown in FIGS. 1A and 1B are predetermined for each identification card in the control process and are precisely positioned in advance to display information that cannot be changed. ing. However, in many cases, external data can be supplied to the circuit unit, data stored in the integrated circuit can be combined and output as information in the integrated circuit, or the storage state in the integrated circuit can be changed in the future. Is desired. Examples suitable for such a purpose include:
For example, it provides data supplied externally through a photocell used to supply electricity to the circuit unit. This circuit unit is shown in FIG.
It may have an external structure as shown in FIG. In this embodiment, the light used to illuminate the photocell consists of a DC component and an AC component that carries the information so that the photocell illuminated by the light modulated by such an applied electrical signal is not modulated. receive. Inside the integrated circuit, the AC component is output through a conventionally known electric filter and, if necessary, applied as appropriate amplified information to the subsequent electronic circuit.

Another possibility of a circuit unit providing external data is illustrated in FIG. In this case, an area 26 is shown on the surface of the circuit unit, which area is isolated from the surroundings and is represented by cross-hatching, in which additional photodiodes are placed in the silicon substrate. It is accumulated. The photodiode converts light modulated according to the information to be input into an electric signal. In FIG. 3, reference numeral 4 represents an integrated circuit chip.

In order to simplify the production of integrated circuits, in the last-mentioned embodiment it is advantageous to separate the light flow for energy supply and the input data. This is, for example,
It can be realized by an optical imaging system in which areas 3 and 26 are illuminated separately. A technically feasible possibility is to separate the light streams based on frequency. The case of separating the light flow according to frequency is described below as one of many possibilities. Area 26 is illuminated by read-in data having a spectrum that is lacking in the infrared (IR) part, while area 3 supplying energy is illuminated solely by IR light. The application of IR light to the energy area improves the properties of the silicon photocell, which is sensitive especially in this range, which allows good performance to be obtained even in small photocell dimensions. In principle, of course, the data input area can, in turn, be illuminated by IR light or light in other spectral ranges. Separation of the light stream at the receiver side is accomplished by a plurality of suitable detectors sensitive to a particular range of light. If multiple physically equivalent detectors were used, areas 3 and 26 would
Each piece is masked by an optical filter that is transparent only to the corresponding light. The situation for these matters is schematically illustrated in FIGS. 4 (A) -4 (D). 4 (A) and 4 (B) show the spectra illuminating zone 3 (energy supply) and zone 26 (data input). 4C and 4D show the area 3 and the area 26.
3 shows the attenuation characteristic curve of a filter that should be used for.

Separating the flow of light according to frequency means that the identification card is illuminated over a large surface within the area of the circuit unit relative to the size of the circuit unit, as compared to separating the flow of light by an optical system. There is a benefit of being able to Therefore, it is not necessary to adjust the light in a conical shape. In the above example, the data output was done by a liquid crystal element which can be applied with the benefit of very low energy requirements. However, these embodiments require a hybrid-structured circuit unit with a combination of different technologies. When the elements required for data output are integrated on a silicon wafer, a monolithic structure circuit unit is realized. This can, in principle, be obtained by using light emitting diode elements that can be integrated directly on the substrate for data display, but in particular areas where the light emitting diode elements consume considerable energy. There are cases where it is not desirable for use in.

FIG. 5 illustrates a reference example. In the case of this circuit unit, data is input or output by capacitance. For this reason, vapor-deposited conductive coatings 30 and 31 are provided on the silicon wafer 1, the two coatings being connected to the integrated circuit 2 by vapor-deposited conductive raised linear bodies (wiring) (not shown). Has been done. As described above, the photocell 3 is provided for supplying energy, and the photocell is directly integrated on the silicon wafer along the integrated circuit 2.

FIG. 6 illustrates the operation of the identification card provided in the last-mentioned circuit in the control unit. A counter electrode 33 for inputting or outputting data is placed on the identification card in the area of the circuit unit, which counter electrode can be considerably larger than the circuit. Also, by using only one of the counter electrodes, which may have a larger surface than the identification card, there are no problems with adjusting the card in the control device. Electrodes made of a transparent material are provided on the transparent and electrically conductive coating 34, so that the light from the light source 35 can reach the photocells of the circuit unimpeded.

According to the so-called "multiplex" method, the control unit communicates with the circuit units of the identification card. Data input and data output are continuously performed within a defined time interval. After starting the circuit, in other words, after a defined time interval after irradiation of the photocell, a signal transit time window for data entry is first formed and then the corresponding light receiving electrode (eg electrode 30 in FIG. 5).
(See) becomes ready for operation. The electrode 33 of the control device acts as a transmitter in this configuration. The integrated circuit produces consecutive "scanning points" in the input window at even intervals. If a voltage pulse generated by the data sending and receiving unit 36 and directed to the applied electrode appears between two scanning points, the logic of the integrated circuit interprets it. For example, if a pulse exists, a logic "1" is set, and if a pulse does not exist between two scanning points, a logic "0" is set.
And The potential of the pulse voltage applied to the conductive coating 30 is defined with respect to the coating 31 deposited on the underside of the silicon wafer and is capacitively maintained at the reference potential by the grounded base plate 40 of the controller. Has been done.

The output of data is carried out according to the principle described above for data input, as soon as the "data output" window is formed after the lapse of a defined time. An electrode 3 which is coupled to the conductive coating 30 during this period and to which a voltage is applied
3 acts as a receiver. The periods of data input and data output can be defined according to methods known in the art by corresponding to the control information that the control device sends to the circuit unit.

[0025]

As described above, according to the present invention, the optical / electrical conversion element is monolithically integrated on the integrated circuit. Therefore, the identification card can be miniaturized and easily manufactured. The DC component light and the AC component light can be separated.

[Brief description of drawings]

FIG. 1 is a plan view (A) and a sectional view (B) of an optical operating circuit unit.

FIG. 2 is a plan view (A) of the circuit unit shown in FIG. 1 incorporated in an identification card and a sectional view when the identification card is provided in the control device.

FIG. 3 is a plan view of an optical actuation circuit unit capable of data input.

FIG. 4 is an optical spectrum characteristic diagram of a light source for supplying energy and inputting data to the circuit unit shown in FIG. 3 ((A)).
(B)), and an attenuation characteristic diagram ((C), (D)) of the filter that masks the data input area and the energy supply area.

FIG. 5 is a cross-sectional view of a capacitance type operating circuit unit.

6 is a cross-sectional view in which the circuit unit of FIG. 5 is provided in the control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Wafer 2 ... Integrated circuit 3 ... Photocell 4 ... Liquid crystal 5 ... Liquid crystal film 6, 7 ... Transparent electrode 8 ... Frame 15 ... Circuit unit 16 ... ID card 36 ... Transceiver

Front Page Continuation (72) Inventor Maurer, Thomas Germany, 8000 Munich 60, Apolloveg 12 (56) References JP 49-60835 (JP, A) Actual development S56-109166 (JP, U) USA Patent 3906460 (US, A) US Patent 4007355 (US, A)

Claims (2)

[Claims] 1. An identification card having an integrated circuit for processing an electric signal on a semiconductor substrate, the identification card having an optoelectronic element for inputting and outputting data and an optoelectronic element for supplying power to the integrated circuit. A card, comprising a common optoelectronic element for data input and power supply, monolithically integrated on the semiconductor substrate, wherein the integrated circuit receives and transmits alternating current to be processed as information. A light emitting diode monolithically integrated with an electronic filter for separating a component and a direct current component of received light to be used for power supply, wherein the optoelectronic device for data output is monolithically integrated on the substrate. Identification card. 2. The identification card according to claim 1, wherein an integrated circuit is arranged on one of the substrates and the remaining part of the substrate is used for optoelectronic coupling devices.