CN110164962B - High breakdown voltage Schottky diode and manufacturing method thereof - Google Patents

High breakdown voltage Schottky diode and manufacturing method thereof Download PDF

Info

Publication number
CN110164962B
CN110164962B CN201910430622.0A CN201910430622A CN110164962B CN 110164962 B CN110164962 B CN 110164962B CN 201910430622 A CN201910430622 A CN 201910430622A CN 110164962 B CN110164962 B CN 110164962B
Authority
CN
China
Prior art keywords
schottky
layer
metal
type
doped
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910430622.0A
Other languages
Chinese (zh)
Other versions
CN110164962A (en
Inventor
冯倩
张涛
张进成
周弘
张春福
胡壮壮
封兆青
蔡云匆
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xidian University
Original Assignee
Xidian University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xidian University filed Critical Xidian University
Priority to CN201910430622.0A priority Critical patent/CN110164962B/en
Publication of CN110164962A publication Critical patent/CN110164962A/en
Application granted granted Critical
Publication of CN110164962B publication Critical patent/CN110164962B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40—Electrodes ; Multistep manufacturing processes therefor
    • H01L29/402—Field plates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66969—Multistep manufacturing processes of devices having semiconductor bodies not comprising group 14 or group 13/15 materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/86—Types of semiconductor device ; Multistep manufacturing processes therefor controllable only by variation of the electric current supplied, or only the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched
    • H01L29/861—Diodes
    • H01L29/872—Schottky diodes

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Ceramic Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Manufacturing & Machinery (AREA)
  • Electrodes Of Semiconductors (AREA)

Abstract

The invention discloses a Schottky diode with high breakdown voltage, which mainly solves the problem that the existing Schottky diode device cannot be widely applied to high-voltage high-power devices due to too low breakdown voltage. It includes: ohmic contact metal Au layer, ohmic contact metal Ti layer and highly doped n-type Ga2O3Substrate and low doped n-type Ga2O3Thin film, low doped n-type Ga2O3The film is provided with a slope groove table, the side wall of the slope groove table is provided with a metal ring, the table surface of the slope groove table is provided with a Schottky electrode Ni layer and a Schottky electrode Au layer, two sides of the Schottky electrode Ni layer and the Schottky electrode Au layer are provided with insulating media, and Schottky field plates are arranged on the Schottky electrode Ni layer, the Schottky electrode Au layer and the insulating media. The invention avoids the sharp and concentrated distribution of the electric field intensity born at the edge of the Schottky junction along with the increase of the voltage during the reverse turn-off, improves the breakdown voltage, and can be used as a power device and a high-voltage switch device.

Description

High breakdown voltage Schottky diode and manufacturing method thereof
Technical Field
The invention belongs to the technical field of microelectronic devices, and particularly relates to a Schottky diode which can be used as a power device and a high-voltage switch device.
Background
As semiconductor devices are applied in more and more technical fields, conventional silicon-based and other narrow bandgap semiconductor diodes have many challenges, in which breakdown voltage is difficult to meet the increasing requirements, and becomes one of the key factors influencing further improvement of device performance. Gallium oxide (Ga)2O3) Compared with the third generation semiconductor material represented by SiC and GaN, the semiconductor material has wider forbidden band width, the breakdown field strength is more than 20 times that of Si and more than 2 times that of SiC and GaN, and theoretically, when a diode device with the same withstand voltage is manufactured, the on-resistance of the device can be reduced to 1/10 of SiC and 1/3 of GaN, and the on-resistance of the device can be reduced to Ga2O3The baliga figure of merit of the material is 18 times that of SiC and 4 times or more that of GaN material, so Ga2O3The semiconductor material is a wide bandgap semiconductor material with excellent performance and suitable for preparing power devices and high-voltage switching devices.
To increase Ga2O3The performance of schottky diode devices must be improved by increasing the breakdown voltage of the device in the reverse off state, while Ga2O3The breakdown of the diode device mainly occurs at the edge terminal of the Schottky junction with concentrated electric field distribution, so to increase the breakdown voltage of the device, the electric field at the Schottky junction must be redistributed, for this reason, the breakdown voltage of the device is increased from 40V to over 240V by adopting a method of adding a field plate, and the on-off ratio of the device is still more than 109. However, the method of simply adding the field plate can only optimize the electric field intensity distribution of the device at the edge of the schottky contact on a two-dimensional structure, which limits the distribution of the electric field intensity, so that the breakdown voltage is still not high enough, and the Ga is limited2O3The application of the Schottky diode in a high-voltage high-power device.
Disclosure of Invention
The present invention is directed to the conventional Ga2O3The defects of the Schottky diode are that the Schottky diode with high breakdown voltage and the manufacturing method thereof are provided, so that the oxide layer with high dielectric constant is adopted as a fieldThe dielectric material below the plate is matched with the metal ring structure prepared on the slope groove with a certain inclination angle, so that the electric field intensity of the device at the Schottky contact edge is uniformly distributed on the three-dimensional structure, the sharp and concentrated distribution of the electric field intensity borne at the edge of the Schottky junction along with the increase of the voltage during reverse turn-off is avoided, and the improvement of the breakdown voltage is realized.
The invention is realized by the following steps:
a high breakdown voltage Schottky diode comprising from bottom to top: ohmic contact metal Au layer 1, ohmic contact metal Ti layer 2 and highly doped n-type Ga2O3Substrate 3 and low doped n-type Ga2O3Film 4, characterized in that:
low doped n-type Ga2O3A slope groove table 5 is formed on the film, a metal ring 6 is arranged on the side wall of the slope groove table 5, and a Schottky electrode Ni layer 7 and a Schottky electrode Au layer 8 are arranged on the table top of the slope groove table 5;
insulating mediums 9 are arranged on two sides of the Schottky electrode Ni layer 7 and the Schottky electrode Au layer 8;
a schottky field plate 10 is provided on the schottky electrode Ni layer 7, the schottky electrode Au layer 8 and the insulating medium 9.
Further, characterized in that the n-type Ga2O3Substrate 3 having electron concentration of 1018cm-3-1019cm-3。
Further, characterized in that the low-doped n-type Ga2O3Film 4 of carrier concentration 1017cm-3-1018cm-3And the thickness is more than 1 μm.
Further, characterized in that the low-doped n-type Ga2O3The slope groove 5 is formed by etching with a plasma etching machine, the etching depth is 400-600nm, and the inclination angle is 40-60 degrees.
Further, it is characterized in that the insulating medium 9 comprises Si3N4、Al2O3、SiO2、HfO2And HfSiO to a thickness of 100nm to 500 nm.
In order to achieve the above object, the method for manufacturing a high breakdown voltage schottky diode according to the present invention comprises the following steps:
1) for highly doped n-type Ga2O3Standard cleaning is carried out on the substrate;
2) putting the cleaned substrate into an MOCVD reaction chamber to epitaxially grow the low-doped n-type Ga with the thickness of 600-2O3A film;
3) placing the substrate after the epitaxy into an electron beam evaporation table at Ga2O3Evaporating metal Ti/Au on the back of the substrate, wherein the thickness of Ti is 20-50nm, the thickness of Au is 100-200nm, and then evaporating metal Ti/Au on the back of N2Carrying out rapid thermal annealing at 550 ℃ for 60s in an environment to form a sample of the ohmic contact electrode;
4) putting the sample into a plasma etching machine, and setting BCl3Gas flow rate of 60sccm, Ar2The gas flow rate of (1) is 20sccm, the pressure of the reaction chamber is 25mT, the radio frequency power is 150W, and in the low-doped n-type Ga2O3Etching a groove with the depth of 400-600nm and the inclination angle of 40-60 degrees;
5) in the low doped n-type Ga2O3Coating photoresist on the substrate, and photoetching to obtain a window for depositing a Schottky electrode;
6) putting the photoetched sample into an electron beam evaporation table, and placing the sample in a low-doped n-type Ga2O3Evaporating and depositing metal Ni/Au, wherein the thickness of the metal Ni is 20-50nm, and the thickness of the metal Au is 100-200 nm;
7) removing the photoresist and the metal on the photoresist from the deposited sample to form a Schottky contact electrode;
8) placing a sample for forming the Schottky contact electrode into a PECVD device, and arranging a reaction gas source SiH4At a flow rate of 40sccm, N2The flow rate of O is 10sccm, the pressure of the reaction chamber is 1-2Pa, the radio frequency power is 40W, and the low-doped n-type Ga2O3And SiO deposited on the Schottky contact electrode with a thickness of 300nm2A film;
9) photoetching the deposited sample to form etched SiO2The window of (1);
10) etching to remove the Ga and the upper part of the Schottky electrode2O3SiO under the side wall of the groove2；
11) Placing the etched sample in an oxygen plasma reaction chamber, setting the oxygen flow at 200sccm, the pressure in the reaction chamber at 30-40Pa, the radio frequency power at 50W, and the etching time at 1min, and removing the photoresist floating glue;
12) photoetching the sample again to form a window for depositing a metal ring and a field plate;
13) putting the sample into an electron beam evaporation table to evaporate metal Ni;
14) and removing the photoresist and the metal on the photoresist from the evaporated sample to form a metal ring and a Schottky contact field plate region, thereby completing the manufacture of the Schottky diode.
Compared with the prior art, the invention has the following advantages:
1. according to the invention, the metal ring is prepared on the slope groove with a certain inclination angle, and the oxide layer with a high dielectric constant is matched with the field plate structure made of the dielectric material, so that the distribution of the edge electric field intensity of the Schottky electrode can be further improved compared with the metal ring on the groove of the common field plate structure, and the distribution of the edge electric field intensity of the Schottky electrode can be more three-dimensionally homogenized compared with the slope groove structure with a certain inclination angle of the metal ring with a planar structure, thereby further improving the breakdown voltage of the device.
2. The invention has simple process because the metal ring and the Schottky contact field plate are subjected to one-time photoetching and metal deposition molding.
Drawings
FIG. 1 is a schematic cross-sectional view of the present invention;
fig. 2 is a schematic flow chart of a manufacturing process of the device of the present invention.
Detailed description of the invention
Referring to fig. 1, the schottky diode with high breakdown voltage manufactured by the present invention includes:
ohmic contact metal Au layer 1, ohmic contact metal Ti layer 2 and highly doped n-type Ga2O3Substrate 3 and low doped n-type Ga2O3Film(s)4, low doped n-type Ga2O3The film is provided with a slope groove table 5, the side wall of the slope groove table 5 is provided with a metal ring 6, the table board of the slope groove table 5 is provided with a Schottky electrode Ni layer 7 and a Schottky electrode Au layer 8, two sides of the Schottky electrode Ni layer 7 and the Schottky electrode Au layer 8 are provided with insulating media 9, and Schottky field plates 10 are arranged on the Schottky electrode Ni layer 7, the Schottky electrode Au layer 8 and the insulating media 9.
The thickness of the ohmic contact Au metal layer 1 is 100nm-200nm, and the thickness of the ohmic contact electrode Ti metal layer 2 is 20nm-50 nm;
the highly doped n-type Ga2O3The substrate 3 has an electron concentration of 1018cm-3-1019cm-3；
The low doped n-type Ga2O3The carrier concentration of the thin film 4 is 1017cm-3-1018cm-3The thickness is more than 1 μm;
the low doped n-type Ga2O3The slope groove 5 is formed by etching with a plasma etching machine, the etching depth is 400-600nm, and the inclination angle is 40-60 degrees;
the thickness of the Schottky electrode Ni layer 7 is 20nm-50nm, and the thickness of the Schottky electrode Au layer 8 is 100nm-200 nm;
the insulating medium 9 comprises Si3N4、Al2O3、SiO2、HfO2And HfSiO, with a thickness of 100nm-500 nm;
the length of the schottky field plate 10 is 1 μm to 3 μm.
Referring to fig. 2, the method for manufacturing the high-breakdown-voltage schottky diode includes the following three embodiments:
example 1 preparation of lowly doped n-type Ga2O3The depth of the slope groove is 400nm, and the inclination angle is 40 degrees.
Step 1, highly doped n-type Ga2O3The substrate is subjected to a standard clean as in fig. 2 (a).
1a) Highly doped n-type Ga2O3The substrate being brought to 80 DEG CCleaning in organic cleaning solution for 20 min;
1b) cleaning the substrate subjected to organic cleaning for 40s by using flowing deionized water;
1c) putting the cleaned substrate into HF H2Etching in the solution with O being 1:1 for 60 s;
1d) ga after etching2O3The substrate was rinsed with flowing deionized water for 60 seconds and blown dry with high purity nitrogen.
Step 2, epitaxially growing low-doped n-type Ga2O3Film, fig. 2 (b).
Putting the cleaned substrate into an MOCVD reaction chamber, and adding TMGa and high-purity O respectively2Setting the temperature of a reaction chamber as 700 ℃, the growth pressure as 120Pa, the TMGa flow as 10sccm and O as a Ga source and an O source2The flow rate is 300sccm, and the low-doped n-type Ga with the thickness of 600nm is epitaxially grown on the substrate2O3A film.
And 3, manufacturing an ohmic contact electrode as shown in figure 2 (c).
3a) Highly doped n-type Ga after epitaxial growth2O3Evaporating metal Ti/Au on the back of the substrate, wherein the thickness of Ti is 20nm, and the thickness of Au is 100 nm;
3b) in N2And carrying out rapid thermal annealing at 550 ℃ for 60s in the environment to form a sample of the ohmic contact electrode.
Step 4, plasma etching the groove, as shown in fig. 2 (d).
Putting the sample into a plasma etching machine, and setting BCl3Gas flow rate of 60sccm, Ar2The gas flow rate of the gas is 20sccm, the pressure of the reaction chamber is 25mT, the radio frequency power is 150W, the etching angle is adjusted to be 40 degrees, and the low-doped n-type Ga is doped2O3The film is etched with a groove with the depth of 400nm and the inclination angle of 40 degrees.
Step 5, evaporating and depositing metal Ni/Au, as shown in figure 2 (e).
5a) After the etching is finished, the low-doped n-type Ga of the sample2O3And coating photoresist on the schottky electrode, and photoetching to obtain a window for depositing the schottky electrode.
5b) Placing the photoetched sample into an electron beam evaporation tableVacuum degree of the electron gun is 6.7 multiplied by 10-3Pa, preheating current of 0.6A, preheating time of 5min, electric field of 8KV, and low doping n-type Ga2O3And (3) evaporating and depositing metal Ni/Au, wherein the thickness of the metal Ni is 20nm, and the thickness of the metal Au is 100 nm.
And 6, stripping the metal, as shown in figure 2 (f).
And removing the photoresist and the metal on the photoresist from the deposited sample to form a Schottky contact electrode.
Step 7, PECVD deposition of SiO2Film, FIG. 2 (g).
Placing a sample for forming the Schottky contact electrode into a PECVD device, and arranging a reaction gas source SiH4At a flow rate of 40sccm, N2The flow rate of O is 10sccm, the pressure of the reaction chamber is 1.5Pa, the radio frequency power is 40W, and the low-doped n-type Ga2O3And SiO deposited on the Schottky contact electrode with a thickness of 300nm2A film.
Step 8, photoetching to form etching SiO2Etching window, etching SiO2See fig. 2 (h).
8a) Photoetching the deposited sample to form etched SiO2The window of (1);
8b) etching to remove the Ga and the upper part of the Schottky electrode2O3SiO under the side wall of the groove2。
Step 9, forming a metal ring and a field plate window by photolithography, as shown in fig. 2 (i).
9a) And placing the etched sample in an oxygen plasma reaction chamber, setting the oxygen flow rate to be 200sccm, the pressure of the reaction chamber to be 30Pa, the radio frequency power to be 50W, and the etching time to be 1min, and removing the photoresist floating glue.
9b) The sample is again lithographically patterned to form windows for the deposited metal rings and field plates.
Step 10, evaporating the metal Ni, as shown in FIG. 2 (j).
The sample was placed in an electron beam evaporation stage with the electron gun vacuum set at 6.7X 10-3Pa, preheating current of 0.6A, preheating time of 5min, electric field of 8KV, and low doping n-type Ga2O3And evaporating and depositing metal Ni.
And step 11, stripping the metal to finish the manufacture, as shown in figure 2 (k).
And removing the photoresist and the metal on the photoresist from the evaporated sample to form a metal ring and a Schottky contact field plate region, thereby completing the manufacture of the Schottky diode.
Example 2 fabrication of lowly doped n-type Ga with an etch depth of 500nm and an angle of inclination of 50 °2O3The ramp-recess high breakdown voltage schottky diode.
Step one, highly doped n-type Ga is treated2O3The substrate is subjected to a standard clean as in fig. 2 (a).
The specific implementation of this step is the same as step 1 of example 1.
Step two, epitaxially growing low-doped n-type Ga2O3Film, fig. 2 (b).
Putting the cleaned substrate into an MOCVD reaction chamber, and adding TMGa and high-purity O respectively2The temperature of the reaction chamber is set to be 800 ℃, the growth pressure is set to be 120Pa, the TMGa flow is set to be 10sccm, and O is used as a Ga source and an O source2Epitaxially growing low-doped n-type Ga with the thickness of 700nm on the substrate at the flow rate of 300sccm2O3A film.
And step three, manufacturing an ohmic contact electrode as shown in figure 2 (c).
3.1) highly doped n-type Ga after epitaxial growth2O3Evaporating metal Ti/Au on the back of the substrate, wherein the thickness of Ti is 30nm, and the thickness of Au is 150 nm;
3.2) in N2And carrying out rapid thermal annealing at 550 ℃ for 60s in the environment to form a sample of the ohmic contact electrode.
Step four, plasma etching the groove, as shown in fig. 2 (d).
Putting the sample into a plasma etching machine, and setting BCl3Gas flow rate of 60sccm, Ar2The gas flow rate of the gas is 20sccm, the pressure of the reaction chamber is 25mT, the radio frequency power is 150W, the etching angle is adjusted to be 50 degrees, and the low-doped n-type Ga is doped2O3And grooves with the depth of 500nm and the inclination angle of 50 degrees are etched on the film.
And step five, evaporating and depositing metal Ni/Au, as shown in figure 2 (e).
5.1) after completion of the etching, lightly doped n-type Ga in the sample2O3And coating photoresist on the schottky electrode, and photoetching to obtain a window for depositing the schottky electrode.
5.2) placing the photoetched sample into an electron beam evaporation table, and setting the vacuum degree of an electron gun to be 6.7 multiplied by 10-3Pa, preheating current of 0.6A, preheating time of 5min, electric field of 8KV, and low doping n-type Ga2O3And (3) carrying out upper evaporation deposition on metal Ni/Au, wherein the thickness of the metal Ni is 40nm, and the thickness of the metal Au is 150 nm.
And step six, stripping the metal, as shown in figure 2 (f).
The specific implementation of this step is the same as step 6 of example 1.
Step seven, depositing SiO by PECVD2Film, FIG. 2 (g).
Placing a sample for forming the Schottky contact electrode into a PECVD device, and arranging a reaction gas source SiH4At a flow rate of 40sccm, N2The flow rate of O is 10sccm, the pressure of the reaction chamber is 1.7Pa, the radio frequency power is 40W, and the low-doped n-type Ga2O3And SiO deposited on the Schottky contact electrode with a thickness of 300nm2A film.
Step eight, photoetching to form etched SiO2Etching window, etching SiO2See fig. 2 (h).
The specific implementation of this step is the same as step 8 of example 1.
Step nine, forming a metal ring and a field plate window by photoetching, as shown in fig. 2 (i).
9.1) placing the etched sample in an oxygen plasma reaction chamber, setting the oxygen flow rate to be 200sccm, the pressure of the reaction chamber to be 35Pa, the radio frequency power to be 50W, and the etching time to be 1min, and removing the photoresist floating glue.
9.2) the sample is again lithographically formed with windows for deposition of the metal rings and field plates.
Step ten, evaporating the metal Ni, as shown in FIG. 2 (j).
The specific implementation of this step is the same as step 10 of example 1.
Step eleven, metal stripping is performed to complete the manufacturing, as shown in fig. 2 (k).
The specific implementation of this step is the same as step 11 of example 1.
Example A production of lightly doped n-type Ga with an etch depth of 600nm and a 60 ℃ Tilt angle2O3The ramp-recess high breakdown voltage schottky diode.
A1 for highly doped n-type Ga2O3The substrate is subjected to a standard clean as in fig. 2 (a).
The specific implementation of this step is the same as step 1 of example 1.
A2, epitaxially growing low-doped n-type Ga2O3Film, fig. 2 (b).
Putting the cleaned substrate into an MOCVD reaction chamber, and adding TMGa and high-purity O respectively2The temperature of the reaction chamber is 850 ℃, the growth pressure is 120Pa, the TMGa flow is 10sccm, and O is used as a Ga source and an O source2The flow rate is 300sccm, and the low-doped n-type Ga with the thickness of 800nm is epitaxially grown on the substrate2O3A film.
And A3, manufacturing an ohmic contact electrode, as shown in figure 2 (c).
Highly doped n-type Ga after epitaxial growth2O3Evaporating metal Ti/Au on the back of the substrate, wherein the thickness of Ti is 50nm, and the thickness of Au is 200 nm; then N is added2And carrying out rapid thermal annealing at 550 ℃ for 60s in the environment to form a sample of the ohmic contact electrode.
And A4, plasma etching the groove, as shown in figure 2 (d).
Putting the sample into a plasma etching machine, and setting BCl3Gas flow rate of 60sccm, Ar2The gas flow rate of the gas is 20sccm, the pressure of the reaction chamber is 25mT, the radio frequency power is 150W, the etching angle is adjusted to be 60 degrees, and the low-doped n-type Ga is doped2O3The film is etched with a groove with the depth of 600nm and the inclination angle of 60 degrees.
A5, metal Ni/Au is evaporated and deposited, as shown in FIG. 2 (e).
After the etching is finished, the low-doped n-type Ga of the sample is firstly doped2O3Coating photoresist on the substrate, and photoetching to obtain a window for depositing a Schottky electrode; then the photoetched sample is put into an electron beam evaporation table, and the vacuum degree of an electron gun is set to be 6.7 multiplied by 10-3Pa, preheating current of 0.6A, preheating time of 5min, electric field of 8KV, and low doping n-type Ga2O3And (3) carrying out upper evaporation deposition on metal Ni/Au, wherein the thickness of the metal Ni is 50nm, and the thickness of the metal Au is 200 nm.
A6, stripping the metal, as shown in FIG. 2 (f).
The specific implementation of this step is the same as step 6 of example 1.
A7, PECVD deposition of SiO2Film, FIG. 2 (g).
Placing a sample for forming the Schottky contact electrode into a PECVD device, and arranging a reaction gas source SiH4At a flow rate of 40sccm, N2The flow rate of O is 10sccm, the pressure of the reaction chamber is 2Pa, the radio frequency power is 40W, and the low-doped n-type Ga2O3And SiO deposited on the Schottky contact electrode with a thickness of 300nm2A film.
A8, photoetching to form and etch SiO2Etching window, etching SiO2See fig. 2 (h).
The specific implementation of this step is the same as step 8 of example 1.
And A9, photoetching to form a metal ring and a field plate window, as shown in figure 2 (i).
Placing the etched sample in an oxygen plasma reaction chamber, setting the oxygen flow rate to be 200sccm, the pressure of the reaction chamber to be 40Pa, the radio frequency power to be 50W, and the etching time to be 1min, and removing the photoresist floating glue; and photoetching the sample to form a window for depositing the metal ring and the field plate.
A10, evaporating Ni metal, as shown in FIG. 2 (j).
The specific implementation of this step is the same as step 10 of example 1.
And A11, stripping metal to finish the manufacture, as shown in figure 2 (k).
The specific implementation of this step is the same as step 11 of example 1.
The above detailed description is only three examples of the present invention and should not be construed as limiting the present invention, and it should be understood by those skilled in the art that the device structure of the present invention can be modified without departing from the spirit of the present invention, and the manufacturing method thereof is not limited to the above disclosure, and all equivalent changes and modifications made by the claims of the present invention shall fall within the scope of the present invention.

Claims (10)

1. A high breakdown voltage Schottky diode comprising from bottom to top: ohmic contact metal Au layer (1), ohmic contact metal Ti layer (2) and highly doped n-type Ga2O3Substrate (3) and low doped n-type Ga2O3A film (4), characterized in that:
low doped n-type Ga2O3A slope groove table (5) is formed on the film, a metal ring (6) is arranged on the side wall of the slope groove table (5), and a Schottky electrode Ni layer (7) and a Schottky electrode Au layer (8) are arranged on the table top of the slope groove table (5);
insulating mediums (9) are arranged on two sides of the Schottky electrode Ni layer (7) and the Schottky electrode Au layer (8);
a Schottky field plate (10) is arranged on the Schottky electrode Ni layer (7), the Schottky electrode Au layer (8) and the insulating medium (9).
2. The diode of claim 1, wherein: highly doped n-type Ga2O3The substrate (3) has an electron concentration of 1018cm-3-1019cm-3。
3. The diode of claim 1, wherein: low doped n-type Ga2O3The carrier concentration of the film (4) is 1017cm-3-1018cm-3And the thickness is more than 1 μm.
4. The diode of claim 1, wherein: the slope groove platform (5) is formed by etching with a plasma etching machine, the etching depth is 400-600nm, and the inclination angle is 40-60 degrees.
5. The diode of claim 1, wherein: the insulating medium (9) comprises Si3N4、Al2O3、SiO2、HfO2And HfSiOOne or more kinds of them, the thickness is 100nm-500 nm.
6. The diode of claim 1, wherein: the length of the Schottky field plate (10) is 1-3 mu m.
7. The diode of claim 1, wherein: the thickness of the ohmic contact metal Au layer (1) is 100nm-200nm, and the thickness of the ohmic contact metal Ti layer (2) is 20nm-50 nm.
8. The diode of claim 1, wherein: the thickness of the Schottky electrode Ni layer (7) is 20nm-50nm, and the thickness of the Schottky electrode Au layer (8) is 100nm-200 nm.
9. A method for manufacturing a high breakdown voltage Schottky diode is characterized in that: the method comprises the following steps:
1) for highly doped n-type Ga2O3Standard cleaning is carried out on the substrate;
2) placing the cleaned substrate into an MOCVD reaction chamber, setting the growth temperature at 700-800 ℃, the growth pressure at 120Pa and the epitaxial growth thickness at 600-800nm2O3A film;
3) putting the substrate after the epitaxy into an electron beam evaporation table, and placing the substrate in a highly doped n-type Ga2O3Evaporating metal Ti/Au on the back of the substrate, wherein the thickness of Ti is 20-50nm, the thickness of Au is 100-200nm, and then evaporating metal Ti/Au on the back of N2Carrying out rapid thermal annealing at 550 ℃ for 60s in an environment to form a sample of the ohmic contact electrode;
4) putting the sample into a plasma etching machine, and setting BCl3Gas flow rate of 60sccm, Ar2The gas flow rate of (1) is 20sccm, the pressure of the reaction chamber is 25mT, the radio frequency power is 150W, and in the low-doped n-type Ga2O3Etching a groove with the depth of 400-600nm and the inclination angle of 40-60 degrees on the film;
5) in the low doped n-type Ga2O3Coating photoresist on the film, and photoetching to obtain a window for depositing a Schottky electrode;
6) putting the photoetched sample into an electron beam evaporation table, and placing the sample in a low-doped n-type Ga2O3Evaporating and depositing metal Ni/Au on the film, wherein the thickness of the metal Ni is 20-50nm, and the thickness of the metal Au is 100-200 nm;
7) removing the photoresist and metal Ni and Au on the photoresist from the deposited sample to form a Schottky contact electrode;
8) placing a sample for forming the Schottky contact electrode into a PECVD device, and arranging a reaction gas source SiH4At a flow rate of 40sccm, N2The flow rate of O is 10sccm, the pressure of the reaction chamber is 1-2Pa, the radio frequency power is 40W, and the low-doped n-type Ga2O3SiO with thickness of 300nm is deposited on the film and the Schottky contact electrode2A film;
9) on deposited SiO2Coating photoresist on the film;
10) photoetching the deposited sample to form etched SiO2The window of (1);
11) etching to remove the Ga and the upper part of the Schottky electrode2O3SiO under the side wall of the groove2；
12) Coating photoresist on the uppermost layer of the etched sample;
13) placing the etched sample in an oxygen plasma reaction chamber, setting the oxygen flow at 200sccm, the pressure in the reaction chamber at 30-40Pa, the radio frequency power at 50W, and the etching time at 1min, and removing the photoresist floating glue;
14) photoetching the sample again to form a window for depositing a metal ring and a field plate;
15) putting the sample into an electron beam evaporation table to evaporate metal Ni;
16) and removing the photoresist and the metal Ni on the photoresist from the evaporated sample to form a metal ring and a Schottky contact field plate region, thereby completing the manufacture of the Schottky diode.
10. The method according to claim 9, wherein 1) highly doped n-type Ga is doped2O3The substrate was subjected to the standard cleaning procedure as follows:
1a) firstly, carrying out organic cleaning;
1b) washing with flowing deionized water;
1c) put into HF: H2Etching in the solution with the ratio of O to 1:1 for 30-60 s;
1d) rinsed with flowing deionized water and blown dry with high purity nitrogen.
CN201910430622.0A 2019-05-22 2019-05-22 High breakdown voltage Schottky diode and manufacturing method thereof Active CN110164962B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910430622.0A CN110164962B (en) 2019-05-22 2019-05-22 High breakdown voltage Schottky diode and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910430622.0A CN110164962B (en) 2019-05-22 2019-05-22 High breakdown voltage Schottky diode and manufacturing method thereof

Publications (2)

Publication Number Publication Date
CN110164962A CN110164962A (en) 2019-08-23
CN110164962B true CN110164962B (en) 2020-11-03

Family

ID=67631958

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910430622.0A Active CN110164962B (en) 2019-05-22 2019-05-22 High breakdown voltage Schottky diode and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN110164962B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111129164B (en) * 2019-12-05 2023-09-26 中国电子科技集团公司第十三研究所 Schottky diode and preparation method thereof
CN111129165B (en) * 2019-12-05 2023-11-28 中国电子科技集团公司第十三研究所 Schottky diode and preparation method thereof
CN111048597B (en) * 2019-12-09 2022-07-29 中国电子科技集团公司第五十五研究所 SBD device and preparation method thereof
CN111192926B (en) * 2020-01-07 2021-09-03 中国电子科技集团公司第十三研究所 Gallium oxide Schottky diode and preparation method thereof
CN111509051A (en) * 2020-04-30 2020-08-07 北京国联万众半导体科技有限公司 Novel millimeter wave Ga2O3Schottky diode

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101710593A (en) * 2009-11-19 2010-05-19 复旦大学 Schottky diode

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8502336B2 (en) * 2011-05-17 2013-08-06 Semiconductor Components Industries, Llc Semiconductor diode and method of manufacture
CN106298508A (en) * 2015-05-27 2017-01-04 北大方正集团有限公司 The manufacture method of Schottky diode and Schottky diode
US10014388B1 (en) * 2017-01-04 2018-07-03 General Electric Company Transient voltage suppression devices with symmetric breakdown characteristics
CN106876484B (en) * 2017-01-23 2019-10-11 西安电子科技大学 High-breakdown-voltage gallium oxide Schottky diode and preparation method thereof
CN106876483B (en) * 2017-01-23 2019-10-11 西安电子科技大学 High-breakdown-voltage Schottky diode and production method
CN106887470B (en) * 2017-01-23 2019-07-16 西安电子科技大学 Ga2O3Schottky diode device structure and preparation method thereof
JP7116409B2 (en) * 2017-02-27 2022-08-10 株式会社タムラ製作所 Trench MOS type Schottky diode

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101710593A (en) * 2009-11-19 2010-05-19 复旦大学 Schottky diode

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Field-Plated Lateralβ-Ga2O3 Schottky Barrier Diode With High Reverse Blocking Voltage of More Than 3 kV and High DC Power Figure-of-Merit of 500 MW/cm2";Zhuangzhuang Hu etal.;《IEEE Electron Device Letters》;20181030;第1564-1567页 *
"Research on the growth of β-(AlGa)2O3 film and the analysis of electrical characteristics of Ni/Au Schottky contact using Tung"s model";Feng Qian etal.;《SUPERLATTICES AND MICROSTRUCTURES》;20180830;第815-819页 *

Also Published As

Publication number Publication date
CN110164962A (en) 2019-08-23

Similar Documents

Publication Publication Date Title
CN110164962B (en) High breakdown voltage Schottky diode and manufacturing method thereof
CN112038416B (en) Schottky diode based on p-type NiO film and inclined plane terminal structure and manufacturing method thereof
CN106373884B (en) Method for manufacturing composite gate dielectric GaN-based insulated gate high electron mobility transistor
CN112038415A (en) Schottky diode based on double-step inclined plane and manufacturing method thereof
CN112038408B (en) Vertical aluminum nitride metal oxide semiconductor field effect transistor based on silicon carbide substrate and preparation method
JP5841726B2 (en) Method for manufacturing gallium nitride based semiconductor device
CN110491932B (en) Gallium nitride Schottky diode and manufacturing method thereof
CN110729362B (en) Low-work-function anode metal-based low-opening-voltage GaN microwave diode and preparation method thereof
CN110164976B (en) Strain gallium oxide MOSFET device structure and preparation method
CN113594234B (en) Preparation method of gallium oxide Schottky diode with low turn-on voltage
KR101261928B1 (en) Manufacturing method for silicon carbide schottky barrier diode
CN111063724A (en) Vertical AlN Schottky diode based on drift region multi-layer gradient doping and manufacturing method
CN115312605A (en) Gallium oxide Schottky diode for improving terminal edge peak value electric field and preparation method thereof
CN113871454A (en) Gallium oxide Schottky barrier diode based on silicon dioxide edge terminal and preparation method thereof
CN114171584A (en) Based on Ga2O3Heterojunction field effect transistor and preparation method thereof
CN109904227B (en) Diamond-based field effect transistor with low-work-function conductive grid and preparation method thereof
CN114023808A (en) AlGaN/GaN heterojunction multi-channel power diode with P-type terminal and manufacturing method
CN112736130A (en) Gallium nitride based high electron mobility transistor and manufacturing method thereof
CN112186033A (en) Gallium nitride junction barrier Schottky diode with slant field plate and manufacturing method thereof
CN112038417B (en) Schottky diode based on paraelectric medium and manufacturing method thereof
CN116435362A (en) Ultra-wide band-gap vertical cascode field effect transistor and preparation method thereof
CN113540208B (en) Vertical GaN Schottky diode based on in-situ growth MIS structure and preparation method thereof
CN116581151B (en) Low-turn-on voltage gallium oxide Schottky diode and preparation method thereof
CN110797390B (en) Enhanced GaNHEMT integrated structure and preparation method thereof
TWI394217B (en) Method for fabricating bipolar transistor

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant