CN110085682B - Resonant tunneling diode and manufacturing method thereof - Google Patents

Abstract

The invention provides a resonant tunneling diode and a manufacturing method thereof. The resonant tunneling diode comprises an n-type GaN substrate layer and n⁺The GaN quantum well layer comprises a GaN collector ohmic contact layer, a first GaN isolating layer, a first Al, N, Ga and N layered structure mixed barrier layer, a GaN quantum well layer, a second Al, N and Ga layered structure mixed barrier layer, a second GaN isolating layer, and N⁺The GaN-based emitter ohmic contact layer comprises a GaN-based emitter ohmic contact layer, an annular electrode, a circular electrode and a passivation layer; the Al, N and Ga layered structure mixed barrier layer comprises an Al layer, an N layer and a Ga layer. The invention can eliminate the electric leakage phenomenon caused by uneven distribution of Al components in the random alloy AlGaN potential barrier.

Description

Resonant tunneling diode and manufacturing method thereof

Technical Field

The present invention relates to the field of electronic technologies, and in particular, to a Resonant Tunneling Diode (RTD) and a method for manufacturing the RTD.

Background

In recent years, third generation wide band gap semiconductor materials typified by gallium nitride GaN and silicon carbide SiC have been rapidly developed in the past decade as a new semiconductor material. The GaN-based semiconductor material and the device have excellent properties such as large forbidden band width, high conduction band discontinuity, high thermal conductivity, high critical field strength, high carrier saturation ratio and high heterojunction interface two-dimensional electron gas concentration.

Terahertz technology is an emerging scientific technology, and attracts many researchers for research due to many unique characteristics and advantages. The frequency range of terahertz is 0.1THz to 10THz, which is between microwave and infrared, so to obtain the frequency of terahertz, a proper device must be selected as a generation source of terahertz wave. The resonant tunneling diode becomes an important choice for realizing a terahertz device source due to the negative differential resistance characteristic of the device. The GaN-based resonant tunneling diode inherits the advantages of a GaN-based compound semiconductor material heterojunction, and has the characteristics of high carrier concentration, high carrier mobility, high working frequency, high power, high temperature resistance and the like, so that the GaN-based resonant tunneling diode becomes a hot spot for research of numerous researchers.

Some companies have now fabricated related IC chips using resonant tunneling diodes, and researchers in many countries have done a lot of work on resonant tunneling diodes. The resonant tunneling diode and the slot antenna are connected in parallel to form a terahertz oscillator, the working frequency of the RTD can reach the terahertz level, but the RTD based on the traditional material has very low output power and cannot meet the requirements of a terahertz source. It is desirable to improve the performance of resonant tunneling diodes through innovations in new materials, new structures, new processes, etc. In terms of new materials, GaN materials are considered. The GaN-based RTD has a wider variation range of the depth of the quantum well than other material RTDs, and has a larger output current and higher output power due to some excellent properties of GaN. More importantly, at the THz working frequency, the output power of the GaN-based device is one to two orders of magnitude higher than that of GaAs, and can reach the power of hundreds of milliwatts or even several watts. Furthermore, the source of the two-dimensional electron gas at the AlAs/GaAs interface is formed by modulation doping, while the two-dimensional electron gas at the GaN-based heterojunction interface is caused by the polarization effect of the material. The I-V characteristic and the current peak-to-valley ratio of the resonant tunneling diode can be effectively improved by selecting proper two-dimensional electron gas. Due to the serious leakage current caused by the random fluctuation and diffusion of the Al component at the AlGaN/GaN heterojunction interface, it is observed under a TEM (Transmission Electron Microscope) that the width of the AlGaN potential barrier at different positions is different, so that the tunneling current of the resonant tunneling diode is partially inhibited, and the direct current I-V characteristic of the device does not meet the simulation theoretical expectation.

Disclosure of Invention

In order to solve the technical defects and shortcomings in the prior art, the invention provides a resonant tunneling diode which comprises an n-type GaN substrate layer and n⁺A GaN collector ohmic contact layer, a first GaN isolating layer, a first Al, N, Ga layered structure mixed barrier layer, a GaN quantum well layer, a second Al, N,Ga layer structure mixed barrier layer, second GaN isolating layer, n⁺The GaN-based emitter ohmic contact layer comprises a GaN-based emitter ohmic contact layer, an annular electrode, a circular electrode and a passivation layer;

the Al, N and Ga layered structure mixed barrier layer comprises an Al layer, an N layer and a Ga layer.

Optionally, the Al layer, the N layer, and the Ga layer are grown separately, and include two Al layers, two Ga layers, and four N layers, where the Al layer and the Ga layer are grown in a staggered manner, and one N layer is spaced between the Al layer and the Ga layer.

Optionally, one side of the first Al, N, Ga layered structure mixed barrier layer, and the second Al, N, Ga layered structure mixed barrier layer closest to the substrate layer are Al layers.

Optionally, the thicknesses of the Al layer, the N layer, and the Ga layer are equal.

Optionally, the thicknesses of the Al layer, the N layer, and the Ga layer are respectively equal, and each layer is 0.1-0.5nm thick.

Meanwhile, the embodiment of the invention also provides a manufacturing method of the resonant tunneling diode, which comprises the following steps:

growing a heavily doped n-type GaN layer, namely a collector ohmic contact layer, on the substrate layer;

growing a first GaN isolation layer on the heavily doped n-type GaN layer;

respectively growing a first Al, N and Ga layered structure mixed barrier layer on the unintended doped GaN buffer layer by taking 1 atomic layer as a unit thickness;

growing a GaN quantum well layer on the Al, N and Ga layered structure mixed barrier;

growing a second Al, N and Ga, N mixed barrier layer on the GaN quantum well layer;

growing a second GaN isolating layer on the second Al, N and Ga layered structure barrier layer;

growing n on the second GaN isolation layer⁺The GaN emitter ohmic contact layer, the annular electrode and the circular electrode;

at said n⁺Depositing SiN passivation layers above the GaN collector ohmic contact layer and the annular electrode, and etching the annular table top to expose the annular electrode;

and (3) making a layer of metal wiring on the SiN medium, and evaporating metal Ti/Au for direct current I-V test.

Optionally, the step of growing the first Al, N, and Ga layered structure mixed barrier layer on the unintentionally doped GaN buffer layer with 1 atomic layer as a unit thickness respectively specifically includes:

adopting a radio frequency plasma assisted molecular beam epitaxy RF-MBE radio frequency plasma assisted molecular beam epitaxy method to grow according to the following sequence: an Al layer, an N layer and a Ga layer, an N layer, and a mixed barrier.

Optionally, the step of growing the first GaN isolation layer on the heavily doped n-type GaN layer specifically includes:

and introducing trimethyl gallium and nitrogen into the reaction chamber, keeping the pressure and the temperature as set values, and growing a first GaN isolating layer.

Optionally, the step of growing the heavily doped n-type GaN layer on the substrate layer specifically includes:

and putting the GaN substrate into an MOCVD reaction chamber, introducing trimethyl gallium and nitrogen into the reaction chamber at the same time, and growing a heavily doped n-type GaN layer according to the set temperature and thickness.

Optionally, growing n on the second GaN isolation layer⁺The steps of the GaN emitter ohmic contact layer, the annular electrode and the circular electrode specifically comprise:

growing a heavily doped + n-type GaN layer, i.e., n, on the unintentionally doped GaN spacer layer⁺A GaN collector ohmic contact layer;

to n⁺Etching the ohmic contact layer of the GaN emitter to form a circular table top, wherein the etching depth is n⁺A GaN collector ohmic contact layer;

are each at n⁺GaN collector ohmic contact layer and n⁺Ti/Al/Ni/Au multilayer metal is evaporated on the ohmic contact layer of the GaN emitter to form a ring electrode and a circular electrode, and the ring electrode is not in contact with the circular table top.

According to the resonant tunneling diode and the manufacturing method thereof provided by the embodiment of the invention, the traditional AlGaN potential barrier is replaced by the mixed potential barrier of the Ga, N, Al and N alternating layers, so that the electric leakage phenomenon caused by uneven distribution of Al components in the random alloy AlGaN potential barrier is eliminated, the influence of random alloy is avoided, and the leakage current is obviously reduced. Meanwhile, in the embodiment of the invention, a mixed barrier of Ga, N and Al and N alternate layer structures is adopted to replace the traditional AlGaN barrier, in the specific embodiment, an AlN layer is arranged at a position close to an emitter, and AlN has larger polarity compared with AlGaN, so that a deeper triangular well is formed at the emitter, high 2DEG (2Dimensional Electron Gas) is obtained, more tunneling electrons are provided for tunneling, and high tunneling current is obtained. The design can obtain the high polarity of AlN and the adjustability of the height of AlGaN potential barrier. When the doping concentration is fixed, the Fermi level moves upwards along with the increase of the forbidden bandwidth, and the tunnel breakdown can occur only by needing larger external voltage to generate current, so that the peak voltage is increased.

Other aspects and features of the present invention will become apparent from the following detailed description, which proceeds with reference to the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Drawings

The following detailed description of embodiments of the invention will be made with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of main components of a resonant tunneling diode according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of a method for manufacturing a resonant tunneling diode according to an embodiment of the present invention;

fig. 3A-3M are schematic product diagrams of different stages of a resonant tunneling diode fabrication process in an embodiment of the invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

The invention firstly provides a resonant tunneling diode, which has a structure shown in figure 1 and comprises an N-type GaN substrate layer 101, an N + GaN collector ohmic contact layer 102, a first GaN isolating layer 103, a first Al, N and Ga layered structure mixed barrier layer 104, a GaN quantum well layer 105, a second Al, N and Ga layered structure mixed barrier layer 106, a second GaN isolating layer 107, an N + GaN emitter ohmic contact layer 108, an annular electrode 109, a circular electrode 110 and a passivation layer 111 which are sequentially arranged;

the Al, N and Ga layered structure mixed barrier layer comprises an Al layer, an N layer and a Ga layer.

In the above embodiment, the circular electrode 110 is provided with the drain metal interconnection 1101, and the ring electrode 109 is provided with the source metal interconnection 1091.

In the above embodiment of the invention, the thickness of the n-type GaN substrate layer is 100-1000nm, preferably 500 nm.

In the above embodiments of the present invention, n⁺The thicknesses of the GaN collector ohmic contact layer and the emitter ohmic contact layer are respectively 120nm and 80nm, and the doping concentrations are respectively 6 multiplied by 10¹⁸And 5X 10¹⁸cm^-3。

In some embodiments of the present invention, the Al layer, the N layer, and the Ga layer are grown separately, and include two Al layers, two Ga layers, and four N layers, wherein the Al layers and the Ga layers are grown alternately, and one N layer is spaced between the Al layers and the Ga layers. Specifically, each layer was 1ML (0.25nm) in thickness for a total of 2 nm.

In some embodiments of the present invention, the thickness of the GaN quantum well layer is 1.8-2.2 nm.

In some embodiments of the present invention, the side of the first Al, N, Ga layered mixed barrier layer, the second Al, N, Ga layered mixed barrier layer closest to the substrate layer is an Al layer.

In some embodiments of the present invention, the Al layer, the N layer, and the Ga layer are equal in thickness.

In some embodiments of the present invention, the thickness of the Al layer, the N layer and the Ga layer are respectively equal, and each layer has a thickness of 0.1-0.5 nm.

Meanwhile, the present invention also provides a method for manufacturing a resonant tunneling diode, as shown in fig. 2, including:

step 201: growing a heavily doped n-type GaN layer on the substrate layer;

step 202: growing a first GaN isolation layer on the heavily doped n-type GaN layer; in a specific embodiment, the process conditions may be selected as follows: introducing trimethyl gallium and nitrogen into the reaction chamber, keeping the pressure at 40Torr, the growth temperature at 930 ℃ and the thickness at 6-9 nm;

step 203: respectively growing a first Al, N and Ga layered structure mixed barrier layer on the unintended doped GaN buffer layer by taking 1 atomic layer as a unit thickness; specifically, the composition ratio of Al and Ga in the first Al, N, and Ga layered structure mixed barrier layer is 1: 1;

step 204: growing a GaN quantum well layer on the Al, N and Ga layered structure mixed barrier; growing a 2nm GaN quantum well by using an MOCVD technology;

step 205: growing a second Al, N and Ga, N mixed barrier layer on the GaN quantum well layer;

step 206: growing a second GaN isolating layer on the second Al, N and Ga layered structure barrier layer by adopting an MOCVD (metal organic chemical vapor deposition) technology; the first GaN isolation layer and the second GaN isolation layer are both unintentionally doped GaN layers, and the thicknesses of the first GaN isolation layer and the second GaN isolation layer are respectively 6-9 nm;

step 207: growing n on the second GaN isolation layer⁺The GaN emitter ohmic contact layer, the annular electrode and the circular electrode;

step 208: at said n⁺Depositing SiN passivation layers above the GaN collector ohmic contact layer and the annular electrode, and etching the annular table top to expose the annular electrode;

step 209: and (3) making a layer of metal wiring on the SiN medium, and evaporating metal Ti/Au for direct current I-V test.

In some embodiments of the present invention, the step of growing the first Al, N, and Ga layered structure mixed barrier layer on the unintentionally doped GaN buffer layer with a unit thickness of 1 atomic layer includes:

adopting a radio frequency plasma assisted molecular beam epitaxy RF-MBE radio frequency plasma assisted molecular beam epitaxy method to grow according to the following sequence: an Al layer, an N layer and a Ga layer, an N layer, and a mixed barrier.

In some embodiments of the present invention, the step of growing the first GaN isolation layer on the heavily doped n-type GaN layer specifically includes:

introducing trimethyl gallium and nitrogen into the reaction chamber, keeping the pressure at 40Torr and the growth temperature at 930 ℃, and growing a first GaN isolating layer with the thickness of 6-9 nm. The second GaN isolation layer is grown in substantially the same manner as the first GaN isolation layer.

In some embodiments of the present invention, the step of growing the heavily doped n-type GaN layer on the substrate layer specifically includes:

and putting the GaN substrate into an MOCVD reaction chamber, introducing trimethyl gallium and nitrogen into the reaction chamber at the same time, growing at 950 ℃ and 120nm in thickness, and growing a heavily doped n-type GaN layer.

In some embodiments of the present invention, the growing n on the second GaN isolation layer⁺The steps of the GaN emitter ohmic contact layer, the annular electrode and the circular electrode specifically comprise:

growing a heavily doped n-type GaN layer on the unintentionally doped GaN isolation layer by MOCVD (metal organic chemical vapor deposition) technology, namely n⁺Ohmic contact layer of GaN emitter, specifically, n⁺The thickness of the ohmic contact layer of the GaN emitter is 80nm, and the doping concentration is 5 multiplied by 10¹⁸cm^-3；

To n⁺Etching the ohmic contact layer of the GaN emitter to form a circular table top, wherein the etching depth is n⁺A GaN collector ohmic contact layer; specifically, the etching depth is 200nm and 10 μm<Diameter D<40μm；

Are each at n⁺GaN collector ohmic contact layer and n⁺Ti/Al/Ni/Au multilayer metal is evaporated on the ohmic contact layer of the GaN emitter to form a ring electrode and a circular electrode, and the ring electrode is not in contact with the circular table top.

The following is a specific embodiment of the method for manufacturing the resonant tunneling diode provided by the invention:

example 1: and manufacturing a GaN quantum well layer with the thickness of 1.8nm and a resonant tunneling diode with the thickness of 2nm and Al, N and Ga mixed barrier with a layered structure.

Step 1, a GaN substrate with a diameter of 1.5 inches is selected, the back surface is thinned to a thickness of 500nm, and a substrate layer 301 is formed as shown in fig. 3A.

Step 2, adopting high-purity nitrogen and triethyl gallium as a nitrogen source and a gallium source respectively, adopting silane gas as an n-type doping source, adopting a Metal Organic Chemical Vapor Deposition (MOCVD) method, and growing a layer with the thickness of 120nm and the doping concentration of 6 multiplied by 10 on a substrate layer 301 under the process conditions of the temperature of 1000 ℃ and the pressure of 40torr as shown in figure 3B¹⁸cm^-3N of (A) to (B)⁺A GaN collector ohmic contact layer 302.

And 3, respectively taking high-purity nitrogen and gallium as a nitrogen source and a gallium source, wherein the gallium source is generated by a radio frequency plasma furnace, and under the process conditions that the flow of nitrogen is 1.6mL/min, the input power of plasma is 400W, the reflected power is 5W and the temperature of the gallium furnace is 850 ℃ by using a radio frequency plasma assisted molecular beam epitaxy RF-MBE method, as shown in figure 3C, in the presence of n⁺A first GaN isolation layer 303 with a thickness of 6nm was grown on the GaN collector ohmic contact layer 302.

And 4, adopting high-purity nitrogen, aluminum and gallium as a nitrogen source, an aluminum source and a gallium source respectively, wherein the aluminum source and the gallium source are both generated by a radio frequency plasma furnace, and under the process conditions that the flow rate of nitrogen is 1.6mL/min, the input power of plasma is 400W, the temperatures of the nitrogen furnace and the aluminum furnace are 5W and the gallium furnace are 900 ℃ and 585 ℃, respectively, as shown in fig. 3D, growing an Al, N, Ga and N alternating layer structure barrier 304 with the total thickness of 2nm and the thickness of each layer of 0.25nm on the first GaN isolating layer 303, wherein the total number of 8 layers is the sequence shown in fig. 3E, and the sequence is respectively a fourth N layer 3048, a second Ga layer 3047, a third N layer 3046, a second Al layer 3045, a second N layer 3044, a first Ga layer 3043, a first N layer 3042 and a first Al layer 3041 from bottom to top.

And step 5, adopting high-purity nitrogen and gallium as a nitrogen source and a gallium source respectively, wherein the gallium source is generated by a radio frequency plasma furnace, and growing a GaN quantum well layer 305 with the thickness of 1.8nm on the first Al, N and Ga layered structure mixed barrier layer 304 by using a radio frequency plasma assisted molecular beam epitaxy RF-MBE method under the process conditions that the flow rate of nitrogen is 1.6mL/min, the input power of plasma is 400W, the reflection power is 5W and the temperature of the gallium furnace is 850 ℃, as shown in FIG. 3F.

And step 6, adopting high-purity nitrogen, gallium and aluminum as a nitrogen source, a gallium source and an aluminum source respectively, wherein the gallium source and the aluminum source are both generated by a radio frequency plasma furnace, and growing a second Al, N and Ga layered structure mixed barrier layer 306 with the total thickness of 2nm and the thickness of each layer of 0.25nm on the GaN quantum well layer 305 by using a radio frequency plasma assisted molecular beam epitaxy (RF-MBE) method under the process conditions that the flow rate of nitrogen is 1.6mL/min, the input power of plasma is 400W, the reflection power is 5W, and the temperatures of the gallium furnace and the aluminum furnace are respectively 850 and 585 ℃, wherein the total thickness of the mixed barrier layer is 8, and the process is shown in figure 3G.

And 7, adopting high-purity nitrogen and gallium as a nitrogen source and a gallium source respectively, wherein the gallium source is generated by a radio frequency plasma furnace, and growing a second GaN isolating layer 307 with the thickness of 2nm on the second Al, N and Ga layered structure mixed barrier layer 306 by using a radio frequency plasma assisted molecular beam epitaxy RF-MBE method under the process conditions that the flow rate of nitrogen is 1.6mL/min, the input power of plasma is 400W, the reflection power is 5W and the temperature of the gallium furnace is 850 ℃, as shown in figure 3H.

Step 8, adopting triethyl gallium and high-purity nitrogen as a gallium source and a nitrogen source respectively, adopting silane gas as an n-type doping source, adopting a Metal Organic Chemical Vapor Deposition (MOCVD) method, and growing the GaN-based material with the thickness of 80nm and the doping concentration of 5 multiplied by 10 on the second GaN isolating layer 307 under the process conditions that the temperature is 1000 ℃ and the pressure is 40Torr¹⁸cm^-3N of (A) to (B)⁺A GaN emitter ohmic contact layer 308, as shown in FIG. 3I.

Step 9, at n⁺Photoetching the ohmic contact layer of the GaN emitter to form a large circular mask pattern with the diameter of 15 mu m, and adopting BCl₃/Cl₂Etching gas source, Reactive Ion Etching (RIE) method, and etching depth to n⁺An upper surface of the GaN collector ohmic contact layer 302 is formedA circular mesa as shown in fig. 3J.

Step 10, sequentially evaporating Ti/Al/Ni/Au multilayer metals with the thicknesses of 30nm/120nm/50nm/160nm on the whole device surface by adopting vacuum electron beam evaporation equipment, and forming a ring electrode 309 and a circular electrode 310 by using a metal stripping process, as shown in FIG. 3K.

And 11, carrying out Rapid Thermal Annealing (RTA) treatment on the whole device under the process conditions of argon atmosphere, 800 ℃ and 30 seconds of annealing time to form ohmic contact.

And step 12, depositing a SiN passivation layer 311 with the thickness of 200nm on the front surface of the device by adopting a PECVD (plasma enhanced chemical vapor deposition) process.

Step 13, using CF₄Gas, using RIE etching, a dielectric layer opening is made in the SiN passivation layer 311, exposing the ring electrode 309 and the circular electrode 310, as shown in fig. 3L.

And step 14, evaporating metal Ti/Au on the carved medium hole, wherein the thickness is 20nm/180nm, and the metal Ti/Au is used for testing a device, and manufacturing the device is finished, as shown in fig. 3M.

It can be seen from the above that, in the resonant tunneling diode and the manufacturing method thereof provided by the embodiments of the present invention, the conventional AlGaN barrier is replaced by the mixed barrier of the Ga, N, Al, and N alternating layers, so that the leakage phenomenon caused by the uneven distribution of the Al component in the random alloy AlGaN barrier is eliminated, the influence of the random alloy is avoided, and the leakage current is significantly reduced. Meanwhile, the embodiment of the invention adopts a mixed barrier of Ga, N and Al, N alternate layer structure to replace the traditional AlGaN barrier, an AlN layer is arranged at the position close to the emitter, and AlN has larger polarity compared with AlGaN, so that a deeper triangular well is formed at the emitter, high 2DEG (2Dimensional Electron Gas) is obtained, more tunneling electrons are provided for tunneling, and high tunneling current is obtained. The design can obtain the high polarity of AlN and the adjustability of the height of AlGaN potential barrier. When the doping concentration is fixed, the Fermi level moves upwards along with the increase of the forbidden bandwidth, and the tunnel breakdown can occur only by needing larger external voltage to generate current, so that the peak voltage is increased.

In summary, the principle and embodiments of the present invention are described herein by using specific examples, and the above descriptions of the examples are only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention, and the scope of the present invention should be subject to the appended claims.

Claims (9)

1. The resonant tunneling diode is characterized by comprising an n-type GaN substrate layer and n⁺The GaN quantum well layer-based GaN multilayer structure comprises a GaN collector ohmic contact layer, a first GaN isolating layer, a first Al, N and Ga layered structure mixed barrier layer, a GaN quantum well layer, a second Al, N and Ga layered structure mixed barrier layer, a second GaN isolating layer, and N⁺The GaN-based emitter ohmic contact layer comprises a GaN-based emitter ohmic contact layer, an annular electrode, a circular electrode and a passivation layer;

the Al, N and Ga layered structure mixed barrier layer comprises an Al layer, an N layer and a Ga layer; the superposition arrangement of the Al, N and Ga layered structure mixed barrier layer is matched with the function of the barrier layer;

the annular electrode is arranged on the n + GaN collector ohmic contact layer etched to the periphery of the circular table top of the n + GaN collector ohmic contact layer on the n + GaN emitter ohmic contact layer;

the circular electrode is arranged on the top layer of the circular table top of the n + GaN emitter ohmic contact layer;

the Al layer, the N layer and the Ga layer are respectively grown and comprise two Al layers, two Ga layers and four N layers, wherein the Al layers and the Ga layers are respectively grown in a staggered mode, and one N layer is arranged between the Al layers and the Ga layers at intervals.

2. The resonant tunneling diode of claim 1, wherein the first Al, N, Ga layered hybrid barrier layer, the second Al, N, Ga layered hybrid barrier layer, and the side closest to the substrate layer are Al layers.

3. A resonant tunneling diode according to claim 1, wherein the Al, N and Ga layers are equal in thickness.

4. A resonant tunneling diode according to claim 1, wherein the Al, N and Ga layers are each of equal thickness, each layer being 0.1-0.5nm thick.

5. A method for manufacturing a resonant tunneling diode is characterized by comprising the following steps:

growing a heavily doped n-type GaN layer, namely a collector ohmic contact layer, on the substrate layer;

growing a first GaN isolation layer on the heavily doped n-type GaN layer;

respectively growing a first Al, N and Ga layered structure mixed barrier layer on the first GaN isolation layer by taking 1 atomic layer as a unit thickness;

growing a GaN quantum well layer on the first Al, N and Ga layered structure mixed barrier;

growing a second Al, N and Ga layered structure mixed barrier layer on the GaN quantum well layer, wherein the second Al, N and Ga layered structure mixed barrier layer is a mixed barrier layer of Al, N and Ga and N;

growing a second GaN isolating layer on the second Al, N and Ga layered structure mixed barrier layer;

growing n on the second GaN isolation layer⁺The GaN emitter ohmic contact layer, the annular electrode and the circular electrode;

at said n⁺Depositing SiN passivation layers above the GaN collector ohmic contact layer and the annular electrode, and etching the annular table top to expose the annular electrode;

and (3) making a layer of metal wiring on the SiN medium: the metal Ti/Au was evaporated for DC I-V testing.

6. The method of claim 5, wherein the step of growing the first Al, N, Ga layered mixed barrier layer on the first GaN isolation layer with a unit thickness of 1 atomic layer comprises:

adopting an RF-MBE radio frequency plasma assisted molecular beam epitaxy method to grow according to the following sequence: an Al layer, an N layer and a Ga layer, an N layer, and a mixed barrier.

7. The method of claim 5, wherein the step of growing a first GaN isolation layer on the heavily doped n-type GaN layer comprises:

and introducing trimethyl gallium and nitrogen into the reaction chamber, keeping the pressure and the temperature as set values, and growing a first GaN isolating layer.

8. The method of claim 5, wherein the step of growing the heavily doped n-type GaN layer on the substrate layer specifically comprises:

and putting the GaN substrate into an MOCVD reaction chamber, introducing trimethyl gallium and nitrogen into the reaction chamber at the same time, and growing a heavily doped n-type GaN layer according to the set temperature and thickness.

9. The method of claim 5, wherein n is grown on the second GaN isolation layer⁺The steps of the GaN emitter ohmic contact layer, the annular electrode and the circular electrode specifically comprise:

growing a heavily doped n-type GaN layer, i.e., n, on the first GaN isolation layer⁺A GaN collector ohmic contact layer;

to n⁺Etching the ohmic contact layer of the GaN emitter to form a circular table top, wherein the etching depth is n⁺A GaN collector ohmic contact layer;

are each at n⁺GaN collector ohmic contact layer and n⁺Ti/Al/Ni/Au multilayer metal is evaporated on the ohmic contact layer of the GaN emitter to form a ring electrode and a circular electrode, and the ring electrode is not in contact with the circular table top.

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