JPS6037592Y2 - micro display - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a micro-display, and particularly to a micro-display using a light emitting diode that can provide clear display and is easy to manufacture.

Conventional micro-displays using light-emitting diodes have been constructed either by using rod-shaped light-emitting diodes or by using a monolithic type in which PN junctions are formed only in necessary parts.

The former is, for example, as shown in Japanese Utility Model Publication No. 49-31520 (the outline of which is shown in FIG. 1a), in which a rod-shaped light emitting diode chip 10 is placed on the diagonal of a parallelogram-shaped substrate 103.
1 was mounted to facilitate assembly.

However, with this method, it is necessary to precisely align the chip 101 with the diagonal line of the substrate 103, which is difficult.

If the character height is further reduced, the electrodes 109 on the surface of the chip 101 become even smaller, making it impossible to take out the lead wires, so there is a limit to how small a display can be made.

In the latter case, for example, as shown in U.S. Pat.
However, in general, the monolithic technology of light emitting diodes requires more advanced technology than that of transistors, and if the light emitting diode substrate is GaP, the electrode 119 is taken out through the insulating film 121. Since it is transparent to the emitted color, separation 115 between the segments is required, and even if the light emitting diode substrate is made of other than GaP, most of them employ a mesa etch method, which is an extremely complicated process.

This proposal was developed in view of the above-mentioned shortcomings, and will be explained in detail below.

FIG. 2 is a plan view showing an embodiment of the present invention, and FIG. 3 is a sectional view taken along the line AA' in FIG.

Reference numeral 1 denotes a wafer of a light emitting diode such as GaP, which has a PN junction 2 at a substantially square depth, and is fixed to a base 3 made of ceramic or the like using a conductive adhesive 4 or the like.

The wafer 1 is divided from the front surface side into a plurality of squares 6, 6, . . . by a groove 5 deeper than the PN junction 2.

This may be done by scribing deeper than usual, or by etching.

The cut groove 5 is filled with a light-shielding insulating material 7 such as black epoxy by coating or pouring.

The divided rectangles 6, 6... each have 1
Only one diagonal line 8°8... is left, and electrodes 9, 9... are provided on the other parts.

A person skilled in the art can decide whether to first provide the electrodes 9, 9, .

In this way, two electrodes 9 provided in one square 6
A thin metal wire 10 or the like is connected to at least one of the ゜9 by wire bonding method or the like, and electrically wired to the front base 3 (
(not shown).

The diagonals 8, 8, . . . are arranged in a diagonal shape in the example shown in the figure, so that each becomes a picture element (segment).

This project has the structure described above, so the squares 6, 6
When a voltage is applied to..., the square 6.6.
It emits light near the PN junction 2 in..., and the light is
Since the light is emitted to the outside only from the diagonal line 8, which is not covered by the electrodes 9, 9..., a bright display can be achieved, and the light is emitted to the adjacent square 6 by the light-shielding insulating material 7. Since no light leaks through, the display becomes clearer.

Since the present invention can be easily refined using the electrode shape and deep grooves, there is no need for the conventional insulating film 121, no need for advanced monolithic technology or complicated mesa etch technology, and the light emitting area is smaller than before. Because it is wide, a high-brightness display can be obtained.

Furthermore, since the electrodes 9, 9, etc. have a sufficient area, a sufficient lead wire extraction area can be obtained even in a small display, and the wiring direction of the lead wires, which are thin metal wires, can be relatively freely chosen. , multi-digit display is also easy.

Furthermore, there is no display distortion due to misalignment as in the conventional case.

A specific example of the size of the display is a rectangular 6 mm, similar to the conventionally used light emitting diode with a side of 400 μm.
, 6...... are 400 μm on a side, then the character height is 1.
1mm indicator (one segment is approx. 560μ long)
m1 width (several tens of μm) can be obtained, but a character height of about 0.5 (when the width of the kerf is 50 μm) can be easily achieved.

The present invention is not limited to the above-mentioned example, but can be applied to all characters, etc. in which the portion without the electrode 9.9 constitutes one picture element.

As described above, in the present invention, a light emitting diode wafer having a PN junction at a substantially angular depth is divided into a plurality of squares by grooves deeper than the PN junction, and the grooves are filled with a light-shielding insulating material. A microscopic display in which the surface of the rectangle is covered with an electrode except for one diagonal line, and the diagonal line not covered by the electrode is used as a picture element, and a substantially triangular part of the electrode is wired with a thin metal wire. Even if the display is small, there is enough area for the wiring, and there is a high degree of freedom in the direction of wiring, and it is possible to obtain a clear and bright compact light-emitting diode display that is easy to manufacture. .

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional display, FIG. 2 is a plan view of an embodiment of the present invention, and FIG. 3 is a sectional view taken along line AA' in FIG. 1...Wafer, 2...PN junction, 3.
...kerf, 6.6...square, 7...
...Light-shielding insulating material, 8゜8...Diagonal, 9
, 9... Electrode.

Claims (1)

[Scope of utility model registration request] A wafer of a light-emitting diode having a PN junction on almost the entire surface with a substantially square depth is divided into a plurality of squares by grooves deeper than the PN junction and shallower than the wafer, and the grooves are filled with a light-shielding insulating material. It is characterized by leaving one diagonal line on the surface of the rectangle and covering the other part with an electrode, using the diagonal line not covered by the electrode as a picture element, and wiring the approximately triangular part of the electrode with a thin metal wire. A micro-indicator.