Method of manufacturing semiconductor light emitting element

Abstract

A method of manufacturing the semiconductor light emitting element comprises a semiconductor layer forming step of forming the multilayered nitride semiconductor layer on the first wafer having a transparent property; a bonding step of bonding the multilayered nitride semiconductor layer to the first wafer; a groove forming step of forming the groove extending from the lower surface of the first wafer to the multilayered nitride semiconductor layer; a light applying step of applying a first light to the lower surface of the multilayered nitride semiconductor layer through the first wafer to reduce a bonding force between the multilayered nitride semiconductor layer and the first wafer; a separating step of separating the first wafer from the multilayered nitride semiconductor layer; and a cutting step of cutting the second wafer along the groove to divide into a plurality of the semiconductor light emitting element.

Description

TECHNICAL FIELD[0001]This invention relates to a method of manufacturing semiconductor light emitting element.BACKGROUND ART[0002]Conventionally, the semiconductor light emitting element having a property of emitting the light having a emitting area from green to ultraviolet is researched. Such the semiconductor light emitting element is exemplified by a light emitting diode (LED) and a laser diode (LD). Such the light emitting diode and the laser diode are made of nitride semiconductor material of GaN type as follows.AlxInyGazBuN[0003]0≦x≦1[0004]0≦y≦1[0005]0≦z≦1[0006]0≦u≦1x+y+z+u=1[0007]The semiconductor light emitting element such as blue light emitting diode and the ultraviolet light emitting diode are used in combination with the phosphor. The blue light emitting diode and the ultraviolet light emitting diode are configured to emit the blue light and the ultraviolet light, respectively. The blue light and the ultraviolet light are converted into the white light by the phosphor. ...

AI Technical Summary

Benefits of technology

[0019]In this case, N2 gas generated in the light applying step is discharged through the groove. Therefore, it is possible to prevent the generation of the crack in the multilayered nitride semiconductor layer. In addition, in the groove forming step, the groove is formed after the multilayered nitride semiconductor layer and the supporting wafer are joined. When the multilayered nitride semiconductor layer is cut to be divided, a plurality of the semiconductor light emitting element comprising a supporting substrate and the multilayered nitride semiconductor on the supporting substrate are obtained. In this case, it is possible to obtain the semiconductor light emitting element comprising the multilayered nitride semiconductor layer and the supporting substrate are securely joined.

[0021]In this case, it is possible omit a new groove forming step of forming the groove to the second wafer. Therefore, it is possible to easily obtain a plurality of the semiconductor light emitting element which is divided.

[0023]In this case, it is possible to form the groove at a short time, compared with a case where the groove is formed by the dicing saw. In addition, it is possible to form the groove having the width which is smaller than the width which is formed by the dicing saw. Consequently, it is possible to manufacture a lot of the semiconductor light emitting element from a second wafer. As a result, it is possible to reduce the cost of the semiconductor light emitting element.

[0027]In this case, it is possible to prevent “the side surface of the multilayered nitride semiconductor layer of the semiconductor light emitting element after cutting” from being exposed to the air. Consequently, it is possible to prevent the foreign matter from adhering the side surface of the multilayered nitride semiconductor layer. As a result, it is possible to prevent the leakage of the electrical current of the semiconductor light emitting element.

Problems solved by technology

However, the sapphire wafer generally has a low electrical conductivity and a low heat conductivity.

Therefore, the device having a semiconductor light emitting element comprising the sapphire wafer is limited its shape.

In addition to the above limitation, the device having the semiconductor light emitting element comprising the sapphire substrate is required to be designed such that the device efficiently radiates the heat.

When the semiconductor light emitting element receives a large amount of the electrical current, the semiconductor light emitting element generates a large amount of heat.

The warpage causes the crack of the sapphire wafer and the multilayered nitride semiconductor layer.

Therefore, the gas pressure of N2 gas causes the crack of micrometer order to the multilayered nitride semiconductor layer.

The crack causes the leakage of the electrical current.

Therefore, in a case where the multilayered nitride semiconductor layer is manufactured according to the method disclosed in Patent literature 1 and Patent literature 2, there is a need to take a long manufacturing time.

In addition to this need, this method required much cost.

That is, when the sapphire wafer is taken out to the outside, there is a possibility of quality loss of the multilayered nitride semiconductor layer.

However, when the semiconductor light emitting element is manufactured by the method disclosed in Patent literature 4, the minute irregularity is formed adjacent to the groove when the groove is formed.

Therefore, when the semiconductor light emitting elements are produced by the cutting, there is a possibility of degradation of the reliability of the bonding between the multilayered nitride semiconductor layer and the supporting wafer which is a part of the supporting substrate.