KR19980054360A - Submount Manufacturing Method of Laser Diode - Google Patents

Abstract

The present invention relates to a method of manufacturing a submount of a laser diode, wherein an insulating film is formed on an upper surface of a substrate, a second electrode is formed first on a lower surface of a substrate, and then the insulating film is etched using a photoresist pattern formed on a predetermined region on the insulating film as a mask. Forming a first electrode and a first solder on the photoresist pattern and the exposed substrate, in turn, removing the first electrode and the first solder on the photoresist pattern and the photoresist pattern and forming a second solder on the second electrode. As a result, the adhesion between the electrode and the substrate and the electrode and the solder can be improved, the laser diode can be assembled regardless of the solder type, and a solder having a constant thickness can be obtained.

Description

Submount Manufacturing Method of Laser Diode

TECHNICAL FIELD The present invention relates to laser diodes, and more particularly to a method of manufacturing a submount of a laser diode.

In general, as a material used as a submount of a semiconductor laser diode, silicon (Si) is mainly used in a low output laser diode which generates little heat during driving.

However, in the case of a visible light laser diode or a high output laser diode that generates a lot of heat during driving, a material having a good thermal conductivity such as silicon carbide (SiC) is used as a submount.

Submounts have a very important effect on the lifetime of the laser diode, so care must be taken when choosing the right solder and material for the fabrication.

Hereinafter, a method of manufacturing a submount of another laser diode according to the related art will be described with reference to the accompanying drawings.

1A to 1D are a manufacturing process perspective view and a process sectional view showing a manufacturing process of a submount according to the prior art.

As shown in FIG. 1A, the electrodes 2 are formed on the upper side and the lower side of the silicon substrate 1.

In this case, the electrode 2 is formed of a Cr / Ni / Au-based or Ti / Pt / Au-based metal.

Subsequently, as shown in FIG. 1B, a U-shaped photoresist 3 pattern is formed on the electrode 2 above the substrate 1.

At this time, the formation of the photoresist 3 pattern is to allow the submount to be freely moved by using a solderless portion when assembling the laser diode.

Then, as shown in FIG. 1C, after depositing the first solder 4 on the electrode 2 including the photoresist 3 pattern on the upper side of the substrate 1, as shown in FIG. 1D, the lift is performed. The photoresist 3 and the first solder 4 formed on the photoresist 3 are removed by a lift off process to form a U-shaped first solder 4 pattern.

Subsequently, the second solder 5 is deposited on the electrode 2 under the substrate 1, and then cut into an appropriate size to complete the submount.

The submount of the laser diode according to the prior art has the following problems.

First, since the solder is formed after the electrode is formed on the substrate, adhesion to the solder is not good when there are contamination or particles on the electrode surface.

Second, when assembling the laser diode, it is difficult to obtain a solder having a certain thickness necessary for assembling the laser diode due to the spreading of the solder, which makes the assembly process difficult.

An object of the present invention is to provide a method of manufacturing a submount of a laser diode that improves the adhesion between the electrode, the substrate, the electrode and the solder, and prevents the spreading of the solder.

Figures 1a to 1d is a manufacturing process perspective view and a process cross-sectional view showing a manufacturing process of the submount according to the prior art

2A to 2E are process perspective and cross-sectional views showing a submount manufacturing process according to the present invention.

Explanation of symbols on the main parts of the drawings

11 substrate 12 insulating film

13 second electrode 14 photoresist

15 first electrode 16 first solder

17: second solder

In the method of manufacturing a submount of a laser diode according to the present invention, an insulating film is formed on an upper surface of the substrate, a second electrode is formed on the lower surface of the substrate, and then the insulating film is etched using a photoresist pattern formed on a predetermined region on the insulating film, followed by photo The first electrode and the first solder are sequentially formed on the resist pattern and the exposed substrate to remove the first electrode and the first solder on the photoresist pattern and the photoresist pattern and to form the second solder on the second electrode. There is a characteristic.

A method of manufacturing a submount of a laser diode according to the present invention having the above characteristics will be described with reference to the accompanying drawings.

Figures 2a to 2e is a process perspective view and a cross-sectional view showing a submount manufacturing process according to the present invention.

As shown in FIG. 2A, an insulating film 12 is formed on the top surface of the substrate 11 by a PECVD process, and a second electrode 13 is formed on the bottom surface of the substrate 11.

At this time, the insulating film 12 is formed of an oxide film or a nitride film.

Subsequently, as shown in FIG. 2B, the U-shaped photoresist 14 pattern is formed in a predetermined region on the insulating film 12, and as shown in FIG. 2C, the BOE is used as a mask as a mask. The substrate 11 is exposed by overetching the exposed insulating film 12 using.

As shown in FIG. 2D, the first electrode 15 and the first solder 16 are sequentially formed on the exposed substrate 11 and the photoresist 14 pattern, and then as shown in FIG. 2E. Likewise, the first electrode 15 having a U-shape and the first electrode 15 and the first solder 16 on the photoresist 14 pattern and the photoresist 14 pattern are removed by a lift off process. The first solder 16 is formed.

Then, the second solder 17 is formed on the second electrode 13, and then cut into a predetermined size to complete the submount of the laser diode.

In the method of manufacturing the submount of the laser diode according to the present invention has the following effects.

First, the photoresist pattern is first formed on the substrate, and then the electrode and the solder are simultaneously formed, thereby improving the adhesion between the electrode and the substrate and the electrode and the solder.

Second, solder is formed only on the electrode, and other parts are separated by an insulating film, so that the solder does not spread to parts other than the U-shaped pattern, enabling the assembly of a laser diode regardless of the type of solder, and the solder having a constant thickness. You can get it.

Claims (3)

Forming an insulating film on the upper surface of the substrate and forming a second electrode on the lower surface of the substrate; Forming a photoresist pattern in a predetermined region on the insulating film; Etching the insulating layer using the photoresist pattern as a mask to expose a predetermined region of the substrate; Sequentially forming a first electrode and a first solder on the photoresist pattern and the exposed substrate; Removing the photoresist pattern and the first electrode and the first solder on the photoresist pattern and forming a second solder on the second electrode. The method of claim 1, wherein the insulating film is formed of an oxide film or a nitride film. 2. The method of claim 1 wherein said etching is overetched.