DE7035173U - DISPLAY DEVICE WITH LIGHTED DISPLAY ELEMENTS USING SEMI-CONDUCTIVE ELEMENTS. - Google Patents

Description

Mitsubishi Denki Kabushiki Kaisha, Tokyo / Japan

Display device with illuminated display elements under Tt> turn semiconducting elements

The invention relates to a display device using a plurality of luminous display elements semiconducting elements and each with a logic circuit or control circuit assigned to each light indicator element using semiconducting elements.

Known such display devices of the type mentioned consist of a substrate, e.g. made of ceramic, light-emitting display elements such as light-emitting diodes, which are on a rope of the substrate are arranged in such a cough that

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they optionally result in predetermined different types of information ^ and each have a logic circuit or control circuit for each luminous display element, which is arranged on other parts of the substrate, and whose output end is to be electrically connected to the associated luminous display element, whereby the predetermined different types of information can be optionally displayed. The electrical connection of the logical circles or control circuits with the associated luminous display elements was made by metallizing the substrate with a suitable metal such as gold. Therefore, the greater the number of types of information to be displayed, the more complicated the gold wiring pattern became and the larger the corresponding display device became.

Accordingly, the invention is based on the object of creating a display device of the type described at the beginning, in which the entire surface of a semiconductor substrate used for production can effectively be used, to reduce the overall size of the display device.

This object is achieved with a display device of the type described by eggs in that, according to the invention, the majority of the logical circles or switching circuits are completely in or is arranged on a substrate made of semiconducting material, the plurality of Leuchtanaeigeelemente fixedly on the substrate is arranged in predetermined positions such that predetermined different types of information can be displayed in a selected manner, and the logic circuits or storage circuits with the corresponding output connections are directly electrically connected to the associated illuminated display elements.

The display device according to the invention has a greater reliability and a higher level of reliability than known devices high level of efficiency and is in their internal

Simple structure. It further welet an improved electrode arrangement and with a reduced number of procedures compared to ear it th known display devices can be produced

The display device according to the invention is preferred This is how the majority of the light indicator elements are structured is completely arranged on a single display look, arranged on the substrate made of semiconducting material, using semiconducting elements.

There is a two-dimensional embodiment of the invention in that each of the logical circles or control circles from a transistor with a collector area and a continuously connected area of the same to it Conductivity type as in the Kollertor area which the associated LED display element is arranged and thus the LED display element with the collector area dee transistor connected 1st.

The LED display element can advantageously be a light-emitting diode using semiconducting elements «

Ausffihrungebebeispiele the invention are in the drawing and are described in more detail below. Show it

fig. 1 is a perspective view of a erfindungsge according to the constructed embodiment of a display device,

Pig. 2 is a sectional view along the line H-II in fig. 1,

fig. 3 shows an equivalent circuit diagram of part of the device after? lg. 1,

Pig. 4 is a schematic plan view of a modification the invention"

Pig 5 is a partial plan view of one on an enlarged scale Part of the device shown in Fig. 4,

Pig. 6 is a sectional view along the line VI-VI in Pig. 5, and

Fig. 7 is an equivalent circuit diagram of part of the in Pig. 5 shown device.

In the drawing are corresponding or similar Parts are denoted by the same reference numerals.

In Pig. 1 and 2 of the drawing, an arrangement is shown which ^{comprises a substrate 1 of a p +} -semiconductor material which is highly doped with a p-type impurity, and further a p-semiconductor layer or a p-region 2, which is on a surface of the substrate 1 is applied, for example, by an epitaxial drawing process. The material for the substrate 1 and the p-region 2 can be semiconducting silicon (Si), germanium (Ge), compounds from the group HI-IV and so on. On that

a multitude of discrete n-regions 3a, b,

g simultaneously to the p-area 2 in a predetermined pattern depending on the various kinds of information to be displayed diffused. In Pig. 1, for example, the areas 3a, b .., g are arranged in a pattern that the digits, from 0 "to 9 can optionally be displayed. It goes without saying that the pattern is not limited to this, and optionally a number of letters or numbers or the like.

The arrangement further comprises a plurality of discrete n * regions 31a, b. ., g and a multitude of discrete η-regions 32a, b .., g, which at the same time in the p-area 2 in the corresponding patterns determined by the pattern for the n-area before 3a * b, .., g are diffused. Each of the n regions 3a, b, .jg is with the associated η range 32a, b, ... or g via the corresponding

the n ^ area 31a, b, ... or as in Pig. 1 shown connected. In other words, the a areas 31a, b, ..yg are port sets of the associated n-areas 32a, "b, ..jg and have 7or certain Resistance values for a purpose which will become clear below.

The n regions 3, 31 and 32 can be formed simultaneously in the p region 2 in a known manner.

Then p-areas 4a, b, .., g are simultaneously transferred into the associated n-areas 32, b, .., g and then n ^ areas 5a, b •• jS simultaneously into the corresponding p-areas 4a, b , * .; g diffuses to form a plurality of transistors, in this case npn transistors.

In Pig. 2 it can be seen that a PiIm 6 made of any suitable electrically insulating material such as silicon oxide (JSLO ₂ ) is arranged on the exposed surface of the p-regions including the various regions 3 * 31, 32, 4 and 5 and a connection 7 for the Power supply is applied to the insulating film 6 in a predetermined pattern. In the example shown, the connection 7 has the shape of a rectangle with enlarged partial areas at predetermined locations, and all diffused areas lie within the rectangle. As shown in Figure 1, where the insulating sheet 6 is shown all transparent, a plurality of input terminals 8a, b, jg are arranged at predetermined positions of the film 6, among which there are no diffused areas, and have connections to the associated therewith p-regions 4a, b, .., g as base regions of the transistors . These internal connections are arranged on the PiIm 6, although they are in Pig. 2 with the exception of the internal. Connection for the input port 8b are not shown before you are marked with 8b. Likewise, in FIG. 2, the transistor formed in the η region has been omitted for the purpose of simplifying the illustration. The n ⁺ regions 5a, b,. _v g as emitter areas are with the p area 2 and from here with the

Substrate 1 of the p ⁺ -type connected by respective internal connections 9a, b, ..., g, which are arranged on the film 6 and the two ends of which are connected by the d ** n! Film 6 into the associated base regions and the p-region: »ch 2 protrude, as shown for example with the connection 9a? on the transistor 5a-4a-32a in FIG.

Me continuously adjoining η-areas 3a, b, .., g which are regarded as continuations of the n-areas 32a, b, .. * g as collector areas of the associated transistors, have elongated β light-emitting diodes 10a, b, arranged on them. .., g using semiconducting elements on their shapes are essentially equal to each other. The formation of the light-emitting diodes can take place in that first the areas 3 »32, 4 and 5 in the p-region can be formed from germanium, for example and then epitaxially a suitable semiconductor material for the light emitting diodes, e.g., a group IH-V compound such as GaAs or Al Ga., gA.8 or a compound of group H-VI with e.g. η conductivity is drawn. The epitaxially grown layer is then grown in a predetermined cough by known methods Method etched away, whereupon p-diffusion regions are formed in the non-etched parts of the layer.

Then relatively small electrodes 11a, b, ., G are attached to the p-diffusion regions of the resulting light-emitting diodes 10a, b .., g, and pieces of a thin metallic wire 12a, b, ..yg, for example made of gold, connect the electrodes 11a , b, .., g with the associated enlarged partial areas of the connection 7 as in Piß. 1 shown. In this way, a luminous display element is completed.

Shows only for the purpose of clear presentation Flg. 2 the electrodes 11a, b, ·., G nioht · The light-emitting diode can preferably by a suitable protective layer such as the FiIi 6, although this is not shown.

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In the arrangement shown in Ίθγ, each of the light-emitting diodes 1C ″ is connected shtrically to the associated transistor 9-4-32 in the toilet, as is shown as an example for the light-emitting diode 1ut and the associated transistor in FIG the p-region 4a as the base region, which is connected to the input connection 8a, the n-emitter region, which is connected via the internal connection a to a point with reference potential, in this case the substrate 1 of the p ⁺ -type, and the n -Area 32 as a collector area, which is connected to the cathode electrode of the light-emitting diode 10a via a resistor represented by the η-area 31a, the anode electrode of which is in turn connected via the electrode 11a to the positive side of a direct current source 13 which is connected via the connection 7 and the substrate 1 of the n ⁺ -type is connectable.

When an input signal is fed to the input terminal 8a, the transistor 9a-4a-32a becomes conductive and causes a current to flow through the light-emitting diode 10a, which causes the light-emitting diode to light gives away.

It can therefore be seen that in the arrangement according to Pig. 1 the application of input signals to some selected ones of the input connections 8a, b, ··; g makes the transistors connected to these conductive, whereupon the associated light-emitting diode can emit light. If, for example, input signals are applied to the input connections 8a, b, ··, f, the associated light-emitting diodes 10a, b,. _v f Lights off and the number ^rt 0 'is displayed. On the other hand, when input signals are applied to the input terminals 8a and f, the associated Leucl diodes 10a and f emit light and display the number "1".

In the arrangement shown in Figs. 1 and 2, a plurality, seven in this Pail, light indicator elements or light-emitting diode] on the substrate made of semiconducting material in a predetermined th patterns arranged to selectively different predetermined

Display types of information, and the associated control haven including the corresponding transistors and resistors for supplying the light-emitting diodes are arranged in the parts of the substrate which are not occupied by the light-emitting diodes. The substrate can therefore be effectively used without wasting available parts of the substrate, resulting in a small display device. If the required pattern has been determined for the indicator elements in advance, it is necessary to "a minimum number of electrodes to be arranged for use in the wiring, leading to simplification of the structure P- leads · In addition, the display device

W a substrate made of semiconducting material instead of a previous one

manufactured electrically insulating substrate such as ceramic. This leads to both an increase in reliability as well as the luminous efficiency of the display device, because the substrate made of semiconducting material is the "ceramic Substrate is superior in thermal conductivity.

In Figs. 4 to 6, in which like numerals are used in Pig. and 2 denote corresponding or similar parts, a modification of the invention is shown. In this modified arrangement, the p-epitaxial region has 2 instead of the n-regions 3 »as shown in Fig. 1 and 2, a single p-region 40 diffused in the center with an area and a profile which suffice a plurality of Form light-emitting display elements on the p-region 40. The display block 50 includes an n region 51, which is said to be epitaxial Drawn semiconducting gallium senide (GaAs) on the p-region 40 is formed, and a plurality of p-regions 52, of only one of which diffuses into the n region 50 in FIG. 6 is shown in a predetermined pattern to a plurality of light emitting diodes 10a, b, .., g as in FIG and 2 shown to result. The electrically insulating film 6 is on the surface of the display block 50 except for Areas attached in which an electrode is connected to each light emitting diode 10 on the p-region 52.

A plurality of control circuits 20, b,. ., g, each egg for each light-emitting diode IC, arranged * The tax-free »2o each comprise a resistor from the n-area 31 and a transistor consisting of the n ⁺ -area 5 as the emitter area, which with the electrode 11 on the corresponding light-emitting diode 10 via the emitter electrode or connection 9 and a line 15 ″ which is formed, for example, from thin gold wire, from the p-region 4 as the base region, which, as in the arrangement shown in FIGS is connected, and from the n-area 32 as a collector area, which is connected to the. Resistance range or n range 31 is connected. Otherwise the arrangement is essentially the same as that in Pig. I and 2 shown.

Up to light-emitting diodes 10 are therefore connected between the emitter electrodes or connections 9 on the associated transistor and a point with Bezig potential or the substrate 1 of the n ⁺ type as shown in FIG. 7, where the light-emitting diode 10a and the associated control circuit are shown as an example . The circle shown in Fig. 7 is from the in 'ig. 3 only differ with regard to the position of the light-emitting diode 10a relative to the transistor. In both figures, the same reference numerals have been used to designate parts that correspond to one another.

The dent which forms the control free 20 and the electrodes or ports 7 and 8 are in the manner as related with Fig. 1 and 2 described above and corresponding to the coughs, as they are predetermined by the pattern of the light emitting diode 10, built up. The p = region 40 is preferably in the epitaxial p-region 2 is formed simultaneously with the formation of the p-region 4 of the transistors.

In the arrangement shown in FIGS. 4 to 6, the display block 50 is beforehand in its predetermined position on the substrate arranged from semiconducting material and has a plurality

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Illuminated display elements or light emitting diodes 10 arranged in a predetermined cough on it. This allows the Leuoht diodes can easily be arranged in a predetermined ratio.

With light display elements formed on a single block made of semiconducting material on the substrate the luminous display elements can be arranged on the substrate in a small area and in a simple manner optionally predetermined different types of information enter.

If the collector area of the transistor, the ei »η rope each Forms control circuits, is expanded, and the associated light-emitting diode is arranged on the extended part of the collector area of the transistor, the electrode on the light-emitting diode be used as the collector electrode of this transistor, from which it can be seen that the electrode structure can be easily formed, resulting in a reduction in the number the manufacturing step leads.

As already mentioned, the invention increases both the reliability and also the lighting efficiency, because that earlier The electrically insulating substrate used is replaced by the substrate made of semiconducting M & terlal, which is a better one Has thermal conductivity.

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Claims (4)

Protection claims e 1. Display device with a plurality of luminous display elements using semiconducting elements and with one logical each assigned to each luminous display element Circle or control circuit using semiconducting elements, characterized in that the maximum number of logic circles or circuits (20a-20g) is arranged completely in or on a substrate made of semiconducting material (2), the plurality of luminous display elements (10a -10g) are fixedly arranged on the substrate in predetermined positions in such a way that predetermined different types of information selected can be displayed, and the logic circuits or control circuits (20a-20g) with the corresponding output connections directly with the associated illuminated display elements (10a - 10g) are electrically connected. Display device according to Claim 1, characterized in that the plurality of luminous display elements (10a-10g) are completely on a single, on the Substrate made of semiconducting material (2) arranged display blank (50) using semiconducting elements 1st. 3. Display device naoh claim 1, characterized in that each of the logisohen circles or Control circuits (20a-20g) consisting of a transistor with a collector area (32a-32g) and one continuous to it adjoining area (31a - 31g, 3a - 3g) of the same conductivity type as the collector area is insisted on the associated Leuoht display element (10a-10g) arranged and thus the light indicator (10a - 10g) with the collector - 12 - area (32a - 32g) of the transistor connected iat. 4. Display device according to one of claims 1 to 3 » because of the fact that the light on the sigs = element a light-emitting diode (10a - 10g) using semiconducting elements? is.