CN1758495A - Dual-wavelength semiconductor laser light-emitting device and manufacturing method thereof - Google Patents

Abstract

A dual-wavelength semiconductor laser light emitting device includes a first laser light emitting element and a second laser light emitting element formed on a substrate. The manufacturing method stacks an active layer of the second laser light emitting element above an upper cladding layer of the first laser light emitting element, so that the first laser light emitting element and the second laser light emitting element have a shared electrode and can respectively oscillate laser with different wavelengths.

Description

Dual-wavelength semiconductor laser light-emitting device and manufacturing method thereof

technical field

The invention relates to a dual-wavelength semiconductor laser light-emitting device and a manufacturing method, in particular to two different laser light-emitting elements on a substrate, and the two different laser light-emitting elements can respectively oscillate laser light of different wavelengths.

Background technique

To form a semiconductor laser light-emitting device with a dual-wavelength laser light-emitting element on a substrate, most of the existing methods are to form two independent laser light-emitting elements on a substrate, and the two light-emitting elements have independent lower cladding layers respectively. , an active layer and an upper cladding layer. Prior art such as US Patent No. 6,468,820 and US Patent Publication No. 2003/0197204 A1 have introduced this related technology in detail, and here only a brief diagram as shown in FIG. 1 is provided as an explanation of the prior art.

As shown in FIG. 1 , on the substrate 30 , there is a first laser light-emitting device region represented by I and a second laser light-emitting device region represented by II. The first lower cladding layer 111 of the first laser light emitting element 10 and the second lower cladding layer 211 of the second laser light emitting element 20 are independently formed on the substrate 30 . The fabrication method of this structure involves multiple etching steps. For example, after depositing the first composite layer 11 , the first composite layer 11 not in the region I must be removed by etching, so that the second laser light emitting device 20 can be formed on the substrate 30 . Moreover, since the second composite layer 21 is also deposited on the surface of the first composite layer 11 when deposited on the substrate 30 , the second composite layer 21 on the first laser area is also removed by etching. Furthermore, the isolation wells 60 of the first laser device 10 and the second laser device 10 are also defined through an etching process.

Since the implementation of the general etching process involves complex steps such as mask formation and removal, too many times of etching will increase the manufacturing cost, which is less economical. Therefore, it is necessary to design a simpler manufacturing method and reduce process steps to manufacture a novel semiconductor laser device with a dual-wavelength laser light-emitting element.

Contents of the invention

The task of the present invention is to provide a dual-wavelength semiconductor laser light-emitting device and its manufacturing method, so as to design a simpler manufacturing method and reduce process steps to manufacture a novel semiconductor laser device with a dual-wavelength laser light-emitting element.

To this end, the present invention provides a dual-wavelength semiconductor laser light-emitting device on the one hand, comprising:

a substrate;

A first laser light-emitting element, formed on the substrate, the first laser light-emitting element has a first lower cladding layer, a first active layer, and a first upper cladding layer; and

A second laser light-emitting element, formed on the substrate, the second laser light-emitting element has a second lower cladding layer, a second active layer, and a second upper cladding layer;

Wherein, the second active layer is stacked on the first upper cladding layer, so that the first upper cladding layer serves as the second lower cladding layer of the second laser light emitting element.

Another aspect of the present invention provides a method for manufacturing a semiconductor laser light-emitting element light-emitting device, the method comprising the following steps:

(a) providing a substrate having a first lower cladding layer, a first active layer, and a first upper cladding layer of a first laser light-emitting element;

(b) using the first upper cladding layer as a second lower cladding layer of a second laser light emitting element, stacking a second active layer and a second upper cladding layer of the second laser light emitting element on above the first upper cladding layer.

According to a dual-wavelength semiconductor laser light-emitting device and manufacturing method of the present invention, the device includes a first laser light-emitting element and a second laser light-emitting element formed on a substrate. The manufacturing method stacks an active layer of the second laser light-emitting element on top of an upper cladding layer of the first laser light-emitting element, so that the first laser light-emitting element and the second laser light-emitting element have a common electrode, and can be respectively Lasers of different wavelengths are oscillated.

Description of drawings

Figure 1: A cross-sectional view of an existing semiconductor laser light emitting device;

Figures 2a-2n: cross-sectional views illustrating process steps of an embodiment of the present invention;

Figures 3a-3l: Cross-sectional views illustrating process steps of another embodiment of the present invention.

simple notation

The first laser light emitting element 10

first composite layer 11

The first n-type lower cladding layer 111

first active layer 112

The first p-type upper cladding layer 113

The first ridge current injection region 113r

The first non-ridge current injection region 113n

The first p-type ohmic contact layer 17

Second laser light emitting element 20

Second Composite Layer 21

Second lower cladding layer 211

second active layer 212

The second n-type upper cladding layer 213

The second ridge current injection region (current injection region in a ridge form) 213r

The second non-ridge current injection region 213n

Groove 23, 25

The second n-type ohmic contact layer 27

n-type substrate 30

passivation layer 40

Masks 51, 52, 53, 54, 55, 56, 57, 58

isolation well 60

Detailed ways

Two embodiments are provided here to illustrate the semiconductor laser light-emitting device and its manufacturing method of the present invention in detail, wherein FIG. 2a to FIG. 2n are used to illustrate embodiment 1, and FIGS. 3a to 3l are used to illustrate embodiment 2.

Referring to FIG. 2 a of Embodiment 1, an n-type substrate 30 composed of GaAs is provided, and the first laser light-emitting element region I and the second laser light-emitting element region II are pre-divided on the n-type substrate 30 . The n-type substrate 30 has a first composite layer 11 on its surface. The first composite layer 11 includes a first n-type lower cladding layer 111 made of AlGaAs, a first active layer 112 of a multiple quantum well structure (multiplequantum well structure) capable of oscillating a specific wavelength, and an n-type lower cladding layer 112 made of AlGaAs. The first p-type upper cladding layer 113 is sequentially stacked on the n-type substrate 30 . The first p-type upper cladding layer 113 is etched to form a first ridge-shaped current injection region 113r and a first non-ridge-shaped current injection region 113n, wherein the first ridge-shaped current injection region 113r is located in the region I.

Referring to FIG. 2b, a mask 51 is formed above the first ridge-shaped current injection region 113r by using a general lithography technique. Next, referring to FIG. 2c, using the existing Metal-Organic Vapor Phase Epitaxial Growth (MOVPE) technology, selectively (selectively) the mask 51, in the first non-ridge current injection region 113n A second active layer 212 and a second n-type upper cladding layer 213 composed of AlGaAs are stacked in sequence above. The second active layer 212 has a multiple quantum well structure capable of oscillating a specific wavelength. The second laser oscillation wavelength can be different from the first laser oscillation wavelength, for example, they are 650nm and 780nm respectively. As shown in FIG. 2 c , the second active layer 212 and the second n-type upper cladding layer 213 are collectively referred to as a second composite layer 21 .

Next, reference is made to Figures 2d-2e. A patterned mask 52 is formed on the surface of the second composite layer 21 . Then, a trench 23 and a trench 25 are defined on the surface of the second n-type upper cladding layer 213 in the region II by etching. Control the etching rate so that the etching will not penetrate the second n-type upper cladding layer 213 and erode the second active layer 212, which means that the bottom of the trench 23 and the trench 25 is still the second n-type upper cladding layer 213 , as shown in Figure 2e. After the mask 52 is removed, the region of the second n-type upper cladding layer 213 between the trench 23 and the trench 25 forms a second ridge-shaped current injection region 213r. On the surface of the second n-type upper cladding layer 213, the second ridge-shaped current injection region 213r, the trench 23 and the trench 25 are excluded, and the remaining area is the second non-ridge-shaped current injection region 213n, as shown in FIG. 2f Show.

Referring to FIG. 2g, a mask 53 is formed over the second ridge current injection region. Then, a passivation layer 40 is conformally formed on the upper surface of the second non-ridge current injection region 213 r by selectively using the existing deposition process, such as CVD or PVD, on the mask 51 and the mask 53 . The passivation layer 40 is used to isolate the second n-type non-ridge current injection region 213n from the second n-type ohmic contact layer to be formed later. The material of the passivation layer 40 can be generally composed of insulating materials containing silicon, oxygen or nitrogen.

Next, the fabrication of the second n-type ohmic contact layer of the second laser light-emitting element will be further described. As shown in FIG. 2h, mask 51 and mask 53 are removed by selective etching. Next, as shown in FIG. 2i, a mask 54 is formed to cover the upper surface of the passivation layer 40 in the region I and the upper surface of the first ridge-shaped current injection region 113r. Next, a second n-type ohmic contact layer 27 covering the upper surface of the passivation layer 40 in the region II and the upper surface of the second ridge-shaped current injection region 213r is deposited selectively on the mask 54 by using PVD technology. , as shown in Figure 2j. The material of the second n-type ohmic contact layer 27 is composed of conductive metal. The mask 54 is then removed by selective etching, as shown in FIG. 2k.

2l-2n further illustrate the fabrication of the first p-type ohmic contact layer of the first laser element. The first p-type ohmic contact layer is the common electrode of the first laser light emitting element 10 and the second laser light emitting element 20 , and the operation method will be described in detail later. As shown in FIG. 21 , a mask 55 is formed to cover the second n-type ohmic contact layer 27 and the passivation layer 40 between the first p-type ridge current injection region 113 r and the second n-type ohmic contact layer 27 . Next, a first p-type ohmic contact layer 17 is deposited selectively on the mask 55 to cover the surface not covered by the mask 55 by PVD technology. The material of the first p-type ohmic contact layer 17 can be composed of conductive metal. Then, as shown in FIG. 2n, the mask 55 is removed by selective etching. It should be noted that after the mask 55 is removed, an isolation well 60 will be formed between the first p-type ohmic contact layer 17 and the second n-type ohmic contact layer 27 .

FIG. 2n shows a dual-wavelength semiconductor laser light-emitting device manufactured according to the present invention. The device includes a first laser light emitting element 10 and a second laser light emitting element 20 formed on a substrate 30 . Wherein the second active layer 212 of the second laser light emitting element 20 is directly stacked above the first upper cladding layer 113 of the first laser light emitting element 10, so the first laser light emitting element 10 and the second laser light emitting element 20 are There is a shared anode (namely the first p-type ohmic contact layer 17). When operating this dual-wavelength semiconductor laser light-emitting device, the shared anode can be grounded, the signal line 1 of the first laser light-emitting element is electrically connected to the first n-type lower cladding layer 111, and the signal line 2 of the second laser light-emitting element is connected to the first n-type lower cladding layer 111. The second n-type ohmic contact layer 27 is electrically connected. In order to make these two laser light-emitting elements operate at different times, when a positive bias is applied to the signal line 1, a negative bias is applied to the signal line 2 at the same time, or a negative bias is applied to the signal line 1 at the same time. A positive bias is applied to the line 2, so that the first laser light-emitting element 10 and the second laser light-emitting element 20 can respectively oscillate the laser light of a specific wavelength at different times. It should be noted that the position of the ground terminal of the present invention is different from that of the prior art shown in FIG. 1 . The conventional ground terminal is generally disposed on the substrate 30 , but the ground terminal of the present invention is disposed on the first ohmic contact layer 17 of the first laser light-emitting element 10 .

Those skilled in the art should understand that a shared cathode structure can also be produced by simply changing the material in the same manner as above.

Next, Example 2 will be described. In Figures 3a-3l of Embodiment 2, the same elements as those of Embodiment 1 use the same reference numerals. In addition, the process steps of Embodiment 2 shown in FIGS. 3a-3c are the same as those in FIG. 2a-2c of Embodiment 1, so they will not be repeated here. Referring directly to FIG. 3d, a mask 56 is formed on the surface of the second composite layer 21 in the region II by using existing lithography technology. Then, selectively etch the second n-type upper cladding layer 213 that is not covered by the mask 51 and the mask 56, and control the etching rate so that the etching will not penetrate the second n-type upper cladding layer 213 and erode to the second n-type upper cladding layer 213. active layer 212 . Therefore, the area of the second n-type upper cladding layer 213 covered by the mask 56 forms the second ridge-shaped current injection region 213r, and excludes the second n-type upper cladding layer 213 of the second ridge-shaped current injection region 213r. The remaining area is the second non-ridge current injection area 213n.

Referring to FIG. 3 e , a passivation layer 40 is deposited on the second non-ridged current injection region 213 n selectively on the mask 51 and the mask 56 using an existing deposition process, such as CVD or PVD. The passivation layer 40 is used to isolate the second n-type non-ridge current injection region 213n from the second ohmic contact layer to be formed later. The material of the passivation layer 40 can be generally composed of insulating materials containing silicon, oxygen or nitrogen.

Next, the fabrication of the second n-type ohmic contact layer of the second laser light-emitting element will be further described. As shown in FIG. 3f, mask 51 and mask 56 are removed by selective etching. Next, as shown in FIG. 3g, a mask 57 is formed to cover the upper surface of the passivation layer 40 in the region I and the upper surface of the first ridge current injection region 113r. Next, as shown in FIG. 3h, a second n-type ohmic contact layer 27 is deposited on the upper surface of the passivation layer 40 covering the area II and the second ridge-shaped current layer selectively on the mask 57 by using PVD technology. The upper surface of the implant region 213r. The material of the second n-type ohmic contact layer 27 can be composed of conductive metal. Then, the mask 57 is removed by selective etching, as shown in FIG. 3i.

3j-3l further illustrate the fabrication of the first p-type ohmic contact layer of the first laser element. As shown in FIG. 3 j , a mask 58 is formed to cover the second n-type ohmic contact layer 27 and the passivation layer 40 between the first ridge current injection region 113 r and the second n-type ohmic contact layer 27 . Next, a first p-type ohmic contact layer 17 is deposited selectively on the mask 58 to cover the surface not covered by the mask 58 by PVD technology, as shown in FIG. 3 k . The material of the first p-type ohmic contact layer 17 can be composed of conductive metal. Then, the mask 58 is removed by selective etching, as shown in FIG. 3l. It should be noted that after the mask 58 is removed, an isolation well 60 will be formed between the first p-type ohmic contact layer 17 and the second n-type ohmic contact layer 27 .

In the semiconductor laser light-emitting device produced in Example 2, as shown in FIG. 31 , the first laser light-emitting element 10 and the second laser light-emitting element 20 also form a shared anode structure on the n-type substrate 30 . The operation mode of this structure is the same as that of Embodiment 1. Likewise, those skilled in the art should understand that the shared cathode structure can also be manufactured by simply changing the materials in the same way as in this case.

The above detailed description of the preferred embodiments hopes to describe the features and spirit of the present invention more clearly, but the preferred embodiments disclosed above do not limit the scope of the present invention. On the contrary, the above description and various changes and equivalent arrangements are all within the scope of protection of the present invention. Therefore, the scope of the claims of the present invention should be interpreted in the broadest way based on the above description, and cover all possible equivalent changes and equivalent arrangements.

Claims (10)

1, a kind of double-wavelength semiconductor laser luminous device comprises:

One substrate;

One first lasing fluorescence element is formed on this substrate, and this first lasing fluorescence element has coating layer on one first time coating layer, one first active layer and one first; And

One second lasing fluorescence element is formed on this substrate, and this second lasing fluorescence element has coating layer on one second time coating layer, one second active layer and one second;

Wherein, this second active layer storehouse this on first coating layer above, make this on first coating layer as second time coating layer of this second lasing fluorescence element.

2, device as claimed in claim 1, wherein this on first coating layer be selected from one of them of a n type coating layer and a p type coating layer.

3, device as claimed in claim 1, wherein this on first coating layer have one first ridged current injection area, this second active layer be formed on get rid of this first ridged current injection area this on first on the coating layer.

4, device as claimed in claim 3, wherein the top of this first ridged current injection area has one first ohmic contact layer, and this first ohmic contact layer is an earth terminal of this device.

5, a kind of method that is used for making semiconductor laser light emitting element light-emitting device, this method comprises the following steps:

(a) provide a substrate, this substrate has coating layer on the one first time coating layer, one first active layer and one first of one first lasing fluorescence element;

(b) coating layer is as one second time coating layer of one second lasing fluorescence element on first with this, and coating layer is in the top of this coating layer on first on one second active layer and one second of this second lasing fluorescence element of storehouse.

6, method as claimed in claim 5, wherein this on first coating layer be selected from one of them of a n type coating layer and a p type coating layer.

7, method as claimed in claim 5, wherein this on first coating layer have one first ridged current injection area, this second active layer storehouse get rid of this first ridged current injection area this on first on the coating layer.

8, method as claimed in claim 7 also comprises step:

(c) patterning this on second coating layer to form one second ridged current injection area;

(d) form one first ohmic contact layer and one second ohmic contact layer respectively in the top of this first ridged current injection area and the top of this second ridged current injection area.

9, method as claimed in claim 8, wherein this first ohmic contact layer is an earth terminal of this device.

10, method as claimed in claim 8, wherein step (c) be included in this on second on the coating layer at least one groove of definition to form this second ridged current injection area.

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