CN106409993A - Epitaxial structure of GaN-based semiconductor device with electromagnetic wave protective structure and preparation method thereof - Google Patents

Abstract

The invention provides an epitaxial structure and a manufacturing method of a GaN-based semiconductor device with an electromagnetic wave protection structure, including a substrate and an epitaxial layer, the epitaxial layer is arranged on the substrate, and the epitaxial layer is N-type from bottom to top The GaN layer, the quantum well and the P-type GaN layer are characterized in that: a protective layer is arranged between the substrate and the epitaxial layer, and the protective layer is a compound composed of III-V group elements, and different compounds are different protective layers, different The protective layers are arranged alternately; the present invention sets the protective layer structure between the substrate and the epitaxial layer, and adopts the III-V group compound as the protective layer, and the protective layer structure can effectively isolate electromagnetic waves from affecting the core structure of the GaN-based semiconductor device. Radiation to prevent GaN-based semiconductor devices from being destroyed.

Description

Epitaxial structure and fabrication of GaN-based semiconductor device with electromagnetic wave protection structure method

technical field

The invention relates to an epitaxial structure of a GaN-based semiconductor device, in particular to an epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure, and belongs to the technical field of semiconductor chip manufacturing.

Background technique

GaN materials and devices have become a research hotspot in recent years, especially GaN-based semiconductor devices, and many GaN-based semiconductor devices work in electromagnetic radiation environments. For a long time, the radiation effect of electromagnetic waves on semiconductor devices has not attracted enough attention. Experiments have proved that after a GaN-based semiconductor device is irradiated by a certain intensity of electromagnetic waves, its parameters will drift, and the early failure time will be shortened. These changes will affect the reliability of semiconductor devices, especially when some sensitive devices work in a high-intensity electromagnetic radiation environment, this effect is particularly prominent.

Taking GaN-based LEDs as an example, the epitaxial structure of GaN-based LEDs is: substrate--N-type GaN--quantum well--P-type GaN. The PN junction of the LED chip is easily radiated by electromagnetic waves, and the PN junction is subject to strong radiation. When the electromagnetic wave is radiated, it will be destroyed, which will cause abnormalities such as reverse leakage of the PN junction, and cause the LED chip to fail.

To sum up, the core components of GaN-based semiconductor devices (such as PN junctions) are vulnerable to radiation from electromagnetic waves during work, resulting in failure of the entire device.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art, to provide a protective structure that isolates electromagnetic waves outside the epitaxial layer of the GaN-based semiconductor LED chip. The protective structure is mainly arranged between the substrate and the epitaxial layer, using III- The group V compound is used as a protective layer, and different compounds are arranged alternately. The protective layer can effectively isolate the radiation of electromagnetic waves and prevent the semiconductor LED chip from being damaged.

In order to achieve the above technical objectives, the technical solution adopted by the present invention is that the epitaxial structure of a GaN-based semiconductor LED chip with an electromagnetic wave protection structure includes a substrate and an epitaxial layer, the epitaxial layer is arranged on the substrate, and the epitaxial layer is formed from From bottom to top, there are N-type GaN layer, quantum well and P-type GaN layer. It is characterized in that: a protective layer is provided between the substrate and the epitaxial layer, and the protective layer is a compound composed of III-V group elements. The compound is in different layers, and the different layers are arranged alternately.

Further, the number of alternate arrangements of different protective layers determines the total number of protective layers, and the total number of protective layers is 2 to 100 layers.

Further, the thickness of each layer of the protective layer is 5-500nm.

Further, the epitaxial layer with the protective layer structure can block electromagnetic waves with a wavelength of 50-5000 nm.

In order to further achieve the above technical objectives, the present invention also proposes a method for manufacturing an epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure, including the following steps:

Step 1. A substrate is provided, and the substrate is divided into a patterned substrate and a planar substrate;

Step 2. growing a protective layer on the substrate, the protective layer includes at least a first protective layer and a second protective layer, the first protective layer and the second protective layer are different compounds composed of III-V group elements, and The first protective layer and the second protective layer are grown alternately in sequence to complete the growth of the protective layer;

Step 3. Growing an N-type GaN layer, a quantum well and a P-type GaN layer sequentially on the protective layer to complete the growth of the epitaxial layer;

Further, the conditions for the growth of the protective layer are as follows: deposition at 500°C-1100°C for 5-30 minutes, the ratio of the substances involved in the growth is, the flow rate of the Group III element source is 30-160 sccm, and the flow rate of the Group V element gas source is The flow rate is 20~160L/min, the flow rate of N ₂ is 30~150L/min, and the flow rate of H ₂ is 5~120L/min.

Further, the GaN-based semiconductor device includes a high-voltage GaN-based diode, a high-frequency GaN-based diode, a GaN-based LED diode or a HEMT transistor.

It can be seen from the above description that the beneficial effect of the present invention is that the epitaxial structure of the GaN-based semiconductor device can effectively block the electromagnetic wave radiation injected from the substrate layer by adding a protective layer structure, so that the electromagnetic wave radiation cannot reach the core components of the semiconductor device ( Such as near the PN junction), it protects the GaN-based semiconductor device and prevents the device from failing due to the influence of electromagnetic waves.

Description of drawings

Fig. 1 is a schematic structural diagram of Embodiment 1 of the present invention.

Fig. 2 is a schematic structural diagram of Embodiment 2 of the present invention.

Fig. 3 is a schematic structural diagram of Embodiment 3 of the present invention.

Fig. 4 is a schematic structural diagram of Embodiment 4 of the present invention.

Description of drawings: 1-substrate, 2-epitaxial layer, 201-N-type GaN layer, 202-quantum well, 203-P-type GaN layer, 3-protection layer, 301-first protection layer, 302-second protection layer, 4-buffer layer.

detailed description

The present invention will be further described below in conjunction with specific drawings and embodiments.

Embodiment 1 is that the substrate 1 is a patterned substrate, and the protective layer 3 is arranged between the substrate 1 and the N-type GaN layer 201. As shown in FIG. 1 , the epitaxial structure of a GaN-based semiconductor LED chip with an electromagnetic wave protection structure, Including a substrate 1 and an epitaxial layer 2, the epitaxial layer 2 is arranged on the substrate 1, and the epitaxial layer is an N-type GaN layer 201, a quantum well 202 and a P-type GaN layer 203 in order from bottom to top, and is characterized in that : A protective layer 3 is provided between the substrate 1 and the N-type GaN layer 201, the pattern of the protective layer 3 is consistent with the pattern of the substrate 1, and the protective layer 3 includes a first protective layer 301 and a second protective layer 302, The first protective layer 301 is a GaN layer with a thickness of 116nm, the second protective layer 302 is AlN with a thickness of 142nm, and the first protective layer 301 and the second protective layer 302 are arranged alternately, so that they are alternated 10 times, and the protective layer 3 is 20 layers, the epitaxial layer with the protective layer 5 structure can block electromagnetic waves with a wavelength of 1060-1068nm.

Embodiment 2 is that the substrate 1 is a patterned substrate, and the substrate 1 is provided with a buffer layer 4, and the protective layer 3 is provided between the buffer layer 4 and the N-type GaN layer 201 on the substrate 1, as shown in FIG. 2 The epitaxial structure of a GaN-based semiconductor LED chip with an electromagnetic wave protection structure includes a substrate 1 and an epitaxial layer 2, the epitaxial layer 2 is arranged on the substrate 1, and the epitaxial layer is N-type GaN from bottom to top. Layer 201, quantum well 202 and P-type GaN layer 203 are characterized in that: a buffer layer 4 is provided on the substrate 1, and a protective layer 3 is provided between the buffer layer 4 and the N-type GaN layer 201, and the protective layer Layer 3 includes a first protective layer 301 and a second protective layer 302, the first protective layer 301 is a GaN layer with a thickness of 116nm, the second protective layer 302 is AlN with a thickness of 142nm, the first protective layer 301 and the second protective layer The protective layers 302 are arranged alternately, 8 times in this way, the protective layer 3 has 16 layers, and the epitaxial layer with the structure of the protective layer 3 can block electromagnetic waves with a wavelength of 1060-1068nm.

Embodiment 3 is that the substrate 1 is a planar substrate, and the substrate 1 is provided with a buffer layer 4, and the protection layer 3 is provided between the buffer layer 4 and the N-type GaN layer 201 on the substrate 1, as shown in FIG. 3 , the epitaxial structure of a GaN-based semiconductor LED chip with an electromagnetic wave protection structure, including a substrate 1 and an epitaxial layer 2, the epitaxial layer 2 is arranged on the substrate 1, and the epitaxial layer is an N-type GaN layer from bottom to top 201. The quantum well 202 and the P-type GaN layer 203 are characterized in that: a buffer layer 4 is provided on the substrate 1, and a protective layer 3 is provided between the buffer layer 4 and the N-type GaN layer 201. The protective layer 3 includes a first protective layer 301 and a second protective layer 302, the first protective layer 301 is a GaN layer with a thickness of 116nm, the second protective layer 302 is AlN with a thickness of 142nm, the first protective layer 301 and the second protective layer The layers 302 are arranged alternately, such that they are alternated 12 times, and the protective layer 3 has 26 layers. The epitaxial layer with the structure of the protective layer 3 can block electromagnetic waves with a wavelength of 1060-1068nm.

Embodiment 4 is that the substrate 1 is a patterned substrate, and the substrate 1 is provided with a buffer layer 4, the buffer layer 4 is provided with an N-type GaN layer 201, and the protective layer 3 is provided between two N-type GaN layers 2 , as shown in FIG. 4, the epitaxial structure of a GaN-based semiconductor LED chip with an electromagnetic wave protection structure includes a substrate 1 and an epitaxial layer 2, and the epitaxial layer 2 is arranged on the substrate 1, and the epitaxial layer is sequentially from bottom to top: The N-type GaN layer 201, the quantum well 202 and the P-type GaN layer 203 are characterized in that: a buffer layer 4 is provided on the substrate 1, an N-type GaN layer 201 is provided on the buffer layer 4, and the buffer layer 4 The N-type GaN layer 201 is arranged between the substrate 1 and the epitaxial layer 2, and a protective layer 3 is arranged between the N-type GaN layer 201 and the N-type GaN layer 201 of the epitaxial layer 2, and the protective layer 3 includes a first protective layer. Layer 301 and second protective layer 302, the first protective layer 301 is a GaN layer with a thickness of 116nm, the second protective layer 302 is AlN with a thickness of 142nm, the first protective layer 301 and the second protective layer 302 are arranged alternately, Alternating in this way 14 times, the protective layer 3 has 28 layers, and the epitaxial layer with the structure of the protective layer 3 can block electromagnetic waves with a wavelength of 1060-1068nm.

The method for manufacturing the epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure in Embodiment 1, the protective layer 3 is two kinds of compounds, the first protective layer 301 is GaN, and the second protective layer 302 is AlN, comprising the following steps:

A substrate 1 is provided, and a GaN layer is grown on the substrate 1. The growth conditions of the GaN layer are as follows: the growth temperature is 550° C., the deposition time is 10.5 minutes, and the ratio of the substances involved in the growth is as follows: the flow rate of TMGa is 80 sccm, the flow rate of N2 The flow rate of NH3 is 60L/min, and the flow rate of H2 is 85L/min; the AlN layer is grown on the GaN layer, and the conditions for the growth of the AlN layer are: growth temperature 580°C, deposition time 15.1min, and the growth material For example, the flow rate of TMAl is 35 sccm, the flow rate of N2 is 75 L/min, the flow rate of NH3 is 60 L/min, and the flow rate of H2 is 85 L/min; the GaN layer and the AlN layer are grown alternately in sequence, and the number of times of alternate growth is 10 Second, the total number of layers of the protective layer 3 is 20 layers, and the growth time of 20 layers is 256min; on the protective layer 3, an N-type GaN layer 201, a quantum well 202 and a P-type GaN layer 203 are grown sequentially to complete the growth of the epitaxial layer 2 .

The present invention is characterized in that a protective layer 3 is provided between the epitaxial layer and the substrate of the GaN-based semiconductor device, and the protective layer 3 is mainly III-V group compounds, such as: AlN, GaN, InN, GaAs, InP, etc. There are at least two kinds of compounds, different compounds are different protective layers, different protective layers are arranged alternately, the number of times of alternate settings determines the number of layers of the protective layer 3, different compounds have different refractive indices, and the wavelengths that can block electromagnetic waves are different. The type and the thickness of each protective layer 3 determine the wavelength of electromagnetic waves that can be blocked; the protective structure can effectively block the radiation of electromagnetic waves and prevent GaN-based semiconductor devices from failing.

GaN-based semiconductor devices to which the protective structure of the present invention is applicable include high-voltage GaN-based diodes, high-frequency GaN-based diodes, GaN-based LED diodes or HEMT transistors.

The present invention and its implementations have been described above, and the description is not limiting. What is shown in the drawings is only one of the implementations of the present invention, and the actual structure is not limited thereto. If a person of ordinary skill in the art is inspired by it, without departing from the inventive concept of the present invention, any structural mode and embodiment similar to the technical solution without creative design shall belong to the protection scope of the present invention.

Claims (7)

1. The epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure, including a substrate (1) and an epitaxial layer (2), the epitaxial layer (2) is arranged on the substrate (1), and the epitaxial layer is viewed from below Up to the top are N-type GaN layer (201), quantum well (202) and P-type GaN layer (203), characterized in that a protective layer (3) is set between the substrate (1) and the epitaxial layer (2) ), the protective layer (3) is a compound composed of III-V group elements, and there are at least two kinds of compounds, and different compounds are different protective layers, and different protective layers are arranged alternately. 2. The epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure according to claim 1, characterized in that: the number of alternate arrangements between different protection layers determines the total number of layers of the protection layer (3), the protection The total number of layers of layer (3) is 2-100 layers. 3. The epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure according to claim 1, characterized in that: the thickness of each layer of the protection layer (3) is 5-500 nm. 4. The epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure according to claim 1, characterized in that: the epitaxial layer with the protective layer (3) structure can block electromagnetic waves with a wavelength of 50-5000 nm. 5. A method for manufacturing an epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure, comprising the steps of: Step 1. Provide a substrate (1), and the substrate (1) is divided into a patterned substrate and a planar substrate; Step 2. Growing a protective layer (3) on the substrate (1), the protective layer (3) at least includes a first protective layer (301) and a second protective layer (302), and the first protective layer (301 ) and the second protective layer (302) are different compounds composed of III-V group elements, and the first protective layer (301) and the second protective layer (302) are grown alternately in sequence to complete the growth of the protective layer (3); Step 3. An N-type GaN layer (201), a quantum well (202) and a P-type GaN layer (203) are sequentially grown on the protection layer (3) to complete the growth of the epitaxial layer (2). 6. The method for manufacturing the epitaxial structure of a GaN-based semiconductor device with electromagnetic wave protection structure according to claim 5, characterized in that, the conditions for the growth of the protective layer (3) are: at 500°C-1100°C, deposit 5~30min, the ratio of the substances involved in the growth is: the flow rate of group III element source is 30~160sccm, the flow rate of group V element gas source is 20~160L/min, the flow rate of N ₂ is 30~150L/min, H ₂ The flow rate is 5~120L/min. 7. The method for manufacturing the epitaxial structure of a GaN-based semiconductor device with an electromagnetic wave protection structure according to claim 5, wherein the GaN-based semiconductor device includes a high-voltage GaN-based diode, a high-frequency GaN-based diode, a GaN-based LED diodes or HEMT transistors.