JPH02134261A - Led array chip - Google Patents

Abstract

PURPOSE:To easily and surely select a quantity-of-light rank by incorporating a bonding pad for connecting a light emitting part to a wire and a memory part for storing the quantity-of-light rank of the light emitting part. CONSTITUTION:An LED array chip is constituted of light emitting parts 2, bonding pads 1 for connecting the light emitting parts to wires and memory parts 3 for storing the quantity-of-light ranks of the light emitting parts 2. Each of the memory parts 3 is constituted of an aluminum pad part 4 against which a needle allowing a current to flow strikes when the quantity-of-light is written, a contact part 5 constituting a memory cell having memory function and a diffusion part 6 and, when the quantity-of-light rank is written, a current is allowed to flow between each of the pad parts and each rear electrode to fuse a contact part 5. The quantity-of-light rank thus written can be read electrically.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an LED array chip, and particularly to an LED array chip used in an LED printer.

[Conventional technology]

When sorting conventional LED array chips by light intensity rank, it is common to measure the light intensity in a wafer state, cut into chips, and then sort by light intensity rank.

[Problem to be solved by the invention]

However, with the above-mentioned conventional LED array chips, when sorting the light intensity rank, the light intensity measurement data and the chip body must be managed separately, so there is a risk of errors due to misrecognition of the chip position, etc. There is a possibility that they will be sorted by light intensity rank, and furthermore, in that case, it is very difficult to confirm, and there is a disadvantage that a large amount of means is required for sorting.

[Means to solve the problem]

The LED array chip of the present invention has, in addition to the light emitting part that is involved in light emission, which is its original function, a pad part for erecting electrodes from the outside as a storage part that can store the light intensity rank by an external electrical method. , an element that performs storage by passing a current through the pad portion, and includes a fuse-like element that is blown by an external current, or a diode element that causes dielectric breakdown.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a plan view showing one embodiment of the present invention, and Fig. 2 is a plan view showing an embodiment of the present invention.
FIG. 3 is a detailed plan view of the storage unit shown in the figure.

The LED array chip shown in FIG.
and a storage section 3 for storing the light intensity rank of the light emitting section 2.

As shown in FIG. 2, the memory section 3 includes an aluminum pad section 4 that is touched by a needle through which a current flows when writing a light intensity rank, and a contact section 5 that constitutes a memory cell having a memory function.
It is composed of a diffusion section 6.

When writing the light intensity rank into the storage section 3, a current is passed between the pad section 4 and the back electrode to melt down the contact section 5.

In addition, in terms of design, it is preferable to widen the diffusion area and make the contact portion 5 small to optimize the current density.

In any case, such a storage unit 3 is an LE shown in FIG.
The D array chip is provided with four, and can write light quantity ranks for 2'=16 ranks. In addition, by arranging such a pattern, it is possible to write a light intensity rank by directly passing a current from outside after measuring the light intensity in a wafer state.

Furthermore, the light quantity ranks written in this way can be electrically read.

FIG. 3 is a plan view showing a modified example of the storage section shown in FIG. 2. FIG.

The storage section shown in FIG. 3 includes a pad section 4 and a contact section 7.
and a diffusion section 8.

This memory section utilizes dielectric breakdown caused by large currents.
A current is passed between the pad portion 4 and the back electrode, but the diffusion area is kept small so that destruction occurs with a small amount of current.

Further, FIG. 4 shows another modification of the storage section shown in FIG. 2. The storage section shown in FIG. 4 includes a pad section 4 and a fuse section 9.

Writing of the light intensity rank is performed by passing a current between the pad section 4 and the common electrode to blow out the fuse section 9.

In any case, the fuse type, in which the light intensity rank is written by blowing, can not only be read electrically, but also visually from the outside.

〔Effect of the invention〕

The LED array chip of the present invention can be easily and reliably sorted by writing the light intensity rank into the storage unit at the same time as the light intensity measurement, and the equipment for writing can be changed by using about four blowers for checking electrical characteristics. A minor change such as adding a needle and controlling the power supply of several tens of volts is sufficient, and if the light intensity rank is read out electrically from the outside at the time of installation and the current is adjusted according to the light intensity rank, the light intensity adjustment is possible. This has the effect of making it easier.

It is a detailed plan view.

1... Bolding pad, 2... Light emitting part, 3... Memory part, 4... Pad part, 5, 7... Contact part, 6, 8...
- Diffusion part, 9...Fuse part.

Claims (1)

[Claims] An LED array chip comprising: a light emitting section; a bollarding pad for connecting the light emitting section to a wire; and a storage section for writing a light intensity rank of the light emitting section.