CN114512395B - P-type nitride epitaxial structure, preparation method and semiconductor device - Google Patents
P-type nitride epitaxial structure, preparation method and semiconductor device Download PDFInfo
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Abstract
The invention discloses a P-type nitride epitaxial structure, a preparation method and a semiconductor device, wherein the P-type nitride epitaxial structure comprises the following steps: a substrate; the U-shaped nitride layer, the P-shaped nitride front layer and the P-shaped nitride composite layer are sequentially grown on the substrate; wherein the P-type nitride front layer is a lightly Mg-doped nitride layer; the P-type nitride composite layer comprises an undoped nitride layer, a co-doped low-acceptor main layer and a magnesium-doped merging layer which are in a periodic structure, wherein the undoped nitride layer, the co-doped low-acceptor main layer and the magnesium-doped merging layer in a single period grow sequentially; the magnesium doped incorporation layer is a heavily doped Mg nitride layer; the co-doped low acceptor main layer is an indium nitride layer doped with Si. The invention can inhibit the self-compensation effect of the dopant and improve the activation rate of the dopant, thereby improving the carrier concentration of the P-type nitride material.
Description
Technical Field
The invention relates to the technical field of semiconductors, in particular to a P-type nitride epitaxial structure, a preparation method and a semiconductor device.
Background
GaN materials have become important materials for the fabrication of light emitting devices, high temperature high power devices and uv detectors due to their excellent properties. P-type doping is an essential important link for manufacturing GaN devices, and therefore attracts attention of many research groups.
Although the technology is continuously developed over the years, the current carrier concentration of P-type GaN material in the industry is still much lower than that of N-type GaN, and the limitation becomes more and more serious with the development of high-performance GaN devices. The main reasons for the low carrier concentration of the P-type GaN material are two factors, namely, the low activation rate of the doping element, the inability of the conventional doping method to inhibit the self-compensation effect of the doping element, and the increase of the concentration of the doping element often causes the carrier concentration of the P-type GaN material to decrease.
Disclosure of Invention
The invention aims to provide a P-type nitride epitaxial structure, a preparation method and a semiconductor device, which can inhibit the self-compensation effect of a dopant and improve the activation rate of the dopant, thereby improving the carrier concentration of a P-type nitride material.
In order to solve the above technical problem, the present invention provides a P-type nitride epitaxial structure, including:
a substrate; and
a U-type nitride layer, a P-type nitride front layer and a P-type nitride composite layer sequentially grown on the substrate;
the P-type nitride front layer is a nitride layer lightly doped with Mg;
the P-type nitride composite layer comprises a non-doped nitride layer, a co-doped low-acceptor main layer and a magnesium-doped merging layer which are in a periodic structure, wherein the non-doped nitride layer, the co-doped low-acceptor main layer and the magnesium-doped merging layer in a single period grow sequentially; the magnesium doped incorporation layer is a heavily doped Mg nitride layer;
the co-doped low acceptor main layer is an indium nitride layer doped with Si.
As a further improvement of the invention, the thickness of the P-type nitride front layer is 0.5-1.5 um, and the doping concentration of Mg in the P-type nitride front layer is 1E18cm-3-1E19cm-3And the doping concentration of Mg in the Mg doping merging layer is greater than that of Mg in the P-type nitride front layer.
As a further improvement of the invention, the doping concentration of Si doped in the indium nitride layer is 1E17cm-3-1E18cm-3。
As a further improvement of the invention, the doping concentration of Mg doped in the Mg doped incorporation layer is 1E20cm-3-1E21cm-3。
As a further improvement of the invention, the period of the periodic structure is 20-300, and the thickness of the P-type nitride composite layer is 50-600 nm.
A preparation method of a P-type nitride epitaxial structure comprises the following steps:
s1, growing a U-shaped nitride layer on the substrate;
s2, growing a P-type nitride front layer on the U-type nitride layer, wherein the P-type nitride front layer is lightly doped with Mg;
s3, introducing ammonia gas, and growing a P-type nitride composite layer on the P-type nitride front layer;
s4, introducing nitrogen, annealing and activating to form a P-type nitride epitaxial structure;
wherein, the growing of the P-type nitride composite layer comprises the following steps:
s31, introducing a nitride metal source, and growing a non-nitride-doped layer;
s32, closing the nitride metal source, introducing an indium source and a silicon source, and growing a co-doped low-acceptor main layer on the non-doped nitride layer, wherein the co-doped low-acceptor main layer is an indium nitride layer doped with Si;
s33, closing the indium source and the silicon source, introducing a magnesium source, and growing a magnesium doped merging layer on the co-doped low-acceptor main layer, wherein the magnesium doped merging layer is a heavily-doped Mg nitride layer;
s34, repeating the steps S31-S33, forming an undoped nitride layer, a co-doped low acceptor layer and a magnesium doped merging layer in a periodic structure on the P-type nitride front layer, wherein the undoped nitride layer, the co-doped low acceptor layer and the magnesium doped merging layer in a single period are grown in sequence.
As a further improvement of the invention, the growth thickness of the P-type nitride front layer is 0.5-1.5 um, and the doping concentration of Mg in the P-type nitride front layer is 1E18cm-3-1E19cm-3And the doping concentration of Mg in the Mg doping merging layer is greater than that of Mg in the P-type nitride front layer.
As a further improvement of the invention, the growth temperature of the P-type nitride composite layer is 900-1050 ℃, wherein the growth temperature of the co-doped low acceptor layer is lower than that of the non-doped nitride layer.
As a further improvement of the invention, the growth time of the non-doped nitride layer is 10s-20s, the growth time of the co-doped low-acceptor main layer is 1s-10s, and the growth time of the magnesium-doped incorporation layer is 1s-10 s.
As a further improvement of the invention, the doping concentration of Si doped in the indium nitride layer is 1E17cm-3-1E18cm-3And the molar ratio of the indium source to the nitride metal source introduced in the step S32 is at least 2.
As a further improvement of the invention, the doping concentration of Mg in the Mg-doped incorporation layer is 1E20cm-3-1E21cm-3。
As a further improvement of the invention, the times of circulating steps S31-S33 in growing the P-type nitride composite layer are 20-300 times, and the thickness of the formed P-type nitride composite layer is 50-600 nm.
A semiconductor device comprising a P-type nitride epitaxial structure as described above.
The invention has the beneficial effects that:
1. according to the method, the U-shaped nitride layer is grown on the substrate to realize flattening, and the lightly doped P-shaped nitride front layer is grown, so that the influence of the weak N type of the U-shaped nitride layer on a subsequent P-shaped layer is avoided, and the influence of a depletion layer is eliminated by the lightly doped Mg P-shaped nitride front layer; the lightly doped P-type nitride front layer plays a transition role in a subsequent heavily doped P-type nitride composite layer, so that the stress and interface state of an epitaxial layer are prevented from being severely influenced by subsequent heavy doping, and the heavy doped Mg blending rate and good surface morphology are promoted;
2. according to the invention, through the design of an epitaxial structure, three layers in the P-type nitride composite layer grow circularly, and the elements are controlled, so that the solubility of the dopant is increased, and the forming energy of the dopant is reduced, thereby inhibiting the self-compensation effect of the dopant, particularly when a co-doped low-acceptor layer grows, an indium source and a silicon source are introduced to form an Si-doped indium nitride layer, the energy level of Mg as an acceptor is reduced to improve the activation rate of the Si-doped indium nitride layer, and the deep energy level is partially filled by doping Si, thereby improving the incorporation efficiency of Mg, improving the concentration of carriers of a P-type nitride material, and being beneficial to the development of manufacturing a nitride device by P-type doping.
Drawings
FIG. 1 is a schematic diagram of the outer structure of a P-type nitride of the present invention;
FIG. 2 is a schematic diagram of the principle and effect of the co-doped low acceptor layer of the present invention;
FIG. 3 is a schematic diagram illustrating the process of growing a P-type nitride compound layer in the outer structure of P-type nitride according to the present invention;
the reference numbers in the figures illustrate: 100. a substrate; 200. a U-shaped nitride layer; 300. a P-type nitride front layer; 400. a P-type nitride composite layer; 401. a non-nitride-doped layer; 402. co-doping a low acceptor main layer; 403. the magnesium is doped into the layer.
Detailed Description
The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.
As described in the background, the low activation rate of the doping elements and the self-compensation result in the low hole concentration of the P-type GaN material, based on the principle that Mg is a deep acceptor in GaN, the energy level is up to 160mev, the highest activation rate in the industry is very low (less than 5%), and the highest carrier concentration of the P-type GaN material is 5E17cm-3And the stability is poor, compared with the activation energy of GaN material N type doped Si element about 20mev, the GaN material is a shallow donor, the activation rate is almost 100%, so the carrier concentration of the N type GaN material is easily in E19cm-3The above; and when the supply concentration of doped Mg is increased in epitaxial growth, deep level (e.g., Mg) is generated due to self-compensation of Mg although the Mg content in GaN can be increasedGaVNLike donor level) hole concentration instead decreases. Therefore, the carrier concentration of P-type is much lower than that of N-type in the industry at present.
Aiming at the technical problem of low concentration of P-type nitride carriers, the inventor finds that through long-term and intensive research, a nitride layer lightly doped with Mg grows on the surface of a substrate through a U-type nitride layer, and then doping elements are controlled through a composite structure, so that the solubility of a dopant can be increased, the self-compensation effect of the dopant can be inhibited, the energy level of an acceptor can be reduced, the activation rate is improved, and the concentration of the P-type nitride material carriers is improved.
Specifically, referring to fig. 1, the present invention provides a P-type nitride epitaxial structure, including:
a substrate 100; and
a U-type nitride layer 200, a P-type nitride front layer 300 and a P-type nitride composite layer 400 sequentially grown on the substrate 100;
wherein the P-type nitride front layer 300 is a nitride layer lightly doped with Mg;
the P-type nitride composite layer 400 comprises a non-nitride-doped layer 401, a co-doped low-acceptor layer 402 and a magnesium-doped merging layer 403 which are in a periodic structure, wherein the non-nitride-doped layer 401, the co-doped low-acceptor layer 402 and the magnesium-doped merging layer 403 in a single period grow in sequence; the magnesium doped incorporation layer 403 is a heavily doped Mg nitride layer;
the co-doped low acceptor layer 402 is an indium nitride layer doped with an Si element.
The invention takes a P-type GaN epitaxial structure as an example to explain the key principle and the process: since the P-type doped Mg acceptor of GaN material is passivated by H to form Mg-H complex, untreated GaN: mg resistivity as high as 108Omega ∙ cm, Mg must be activated after growth, breaking Mg-H bonds to get a low-resistance P-type GaN material. Therefore, the activation rate of Mg is improved in the following two aspects, so that the concentration of carriers of the P-type nitride material is improved.
The invention firstly grows U-shaped GaN on a substrate 400, has the function of making a heterogeneous substrate transition to a flat GaN material layer, and grows a P-shaped GaN preposed layer, namely a GaN layer with light doping Mg after the growth of the U-shaped GaN material is finished, wherein the thickness of the layer is related to the doping concentration of the GaN layer, and the invention is not particularly limited, is set for the subsequent growth and has two functions: the effect is to eliminate the influence of the depletion layer, and the bottom layer is made of U-shaped GaN material, but the N-type is still weakened due to the nature of the GaN material. In order to avoid the influence on the subsequent P type layer, the layer is lightly doped with Mg, the neutralization of a depletion layer is carried out, and the doping concentration refers to the thickness and the background concentration of the U type layer. And the second function is to provide stress release and interface state for the later highly doped P-type layer. The Mg doping of the highly doped P type will be in E20cm-3-E21cm-3The stress and interface state of the epitaxial layer can be severely influenced by the high doping, and the P-type GaN front layer plays a transition role, so that the high doping P-type Mg incorporation rate and good surface morphology are promoted. In the invention, the thickness of the P-type GaN preposed layer is about 0.5-1.5 um and is larger than that of the P-type GaN composite layer. The P-type nitride front layer is used as a part of the P-type epitaxial layer,the thickness of the whole epitaxial structure is larger, the weak N type of the U-shaped GaN is favorably neutralized, and the transition effect on the heavily doped Mg nitride layer in the subsequent P-shaped GaN composite layer is realized.
When designing a P-type GaN composite layer structure, a 3-layer cycle arrangement is adopted, wherein in the InN material formed in the co-doped low acceptor layer 402 is actually similar to InN quantum dots, as shown in fig. 2, since the forbidden bandwidth of InN is smaller than that of GaN, the activation energy Ea2 of Mg atoms from the valence band top to the acceptor is smaller than that of GaN material Ea1, the valence band top of the formed co-doped low acceptor layer 402 is raised, and the activation energy Ea of Mg atoms of the acceptor is lowered. Meanwhile, due to the doping of Si atoms, partial filling of deep energy level can be realized, and more Mg atoms are liberated to become free particles. When Mg atoms are paved on the P-type GaN material, namely, the magnesium doped merging layer 403 grows, after the magnesium doped merging layer is subjected to energy band processing such as early stress release and co-doping of low acceptors, the merging efficiency and activity of magnesium are greatly improved, and then the non-doped GaN layer is arranged in a circulating mode, so that the crystallization quality is higher, and the P-type GaN material with high hole carrier concentration is formed. In the invention, the doping concentration of doping Si into InN is 1E17cm-3-1E18cm-3(ii) a The Mg doping concentration of the Mg doping incorporation layer 403 is 1E20cm-3-1E21cm-3。
Further, the thickness of the non-nitride-doped layer 401, the co-doped low acceptor layer 402 and the magnesium-doped incorporation layer 403 in each period is 2-4 nm. When the P-type GaN composite layer is a non-nitride-doped layer 401, a co-doped low-acceptor layer 402 and a magnesium-doped merging layer 403 which are cyclically arranged in a multi-period manner, each layer can reduce the Mg atom activation energy of an acceptor, and meanwhile, Si doping of each layer can realize filling of deep energy levels and realize more Mg merging efficiency; and the non-nitride-doped layer 401 is grown by slightly raising the temperature during each cycle, so that the overall crystallization quality is improved. In the invention, the period of the periodic structure is 20-300, and the thickness of the P-type GaN composite layer is 50nm-600 nm. For the PIN device, the cycle is 200-300 periods, and the thickness of the P-type GaN composite layer is 400nm-600 nm. For the GaN-based LED, the cycle is 20-50 cycles, and the thickness of the P-type GaN composite layer is 50nm-125 nm.
The P-type nitride epitaxial structure can be prepared by the following preparation method, and comprises the following steps:
s1, growing a U-shaped nitride layer 200 on the substrate 100;
specifically, a1 μm-3 μm U-shaped nitride layer 200 is grown on a substrate; the U-shaped nitride layer 200 transitions the foreign substrate to a flat GaN material layer;
s2, growing a P-type nitride front layer 300 on the U-type nitride layer 200, wherein the P-type nitride front layer 300 is lightly doped with Mg;
specifically, a P-type nitride front layer 300 of 0.5um to 1.5 μm is grown on the U-type nitride layer 200; wherein the doping concentration of Mg element in the P-type nitride front layer 300 is 1E18cm-3-1E19cm-3；
The lightly doped P-type nitride front layer 300 avoids the influence of the weak N-type of the U-type nitride layer on the subsequent P-type layer, and eliminates the influence of the depletion layer; the lightly doped P-type nitride front layer plays a transition role in subsequent heavy doping, so that the stress and interface state of an epitaxial layer are prevented from being severely influenced by the subsequent heavy doping, and the heavy doping Mg incorporation rate and good surface morphology are promoted;
s3, introducing ammonia gas, keeping the introduction state of the ammonia gas in the whole process, controlling the growth temperature of 900-1050 ℃, and growing a P-type nitride composite layer 400 on the P-type nitride front layer 300;
specifically, as shown in fig. 3, growing the P-type nitride composite layer 400 includes the steps of:
s31, introducing a nitride metal source into the reaction chamber, and growing the non-nitride-doped layer 401 for 10-20S;
s32, closing the nitride metal source, introducing the indium source and the silicon source, and growing the co-doped low acceptor layer 402 on the non-nitride layer 401, wherein the doping concentration of Si is 1E17cm-3-1E18cm-3The molar ratio of the indium source to the nitride metal source is at least 2 to form InN (In cannot be doped when the molar ratio is too low), and the growth time of the co-doped low acceptor layer 402 is 1s to 10 s; preferably, the molar ratio of the indium source to the nitride metal source is optimal from 2 to 5;
when the layer is grown, due to the higher temperature, the formed InN material is actually similar to InN quantum dots, because the forbidden bandwidth of InN is smaller than that of GaN, the activation energy Ea2 of Mg atoms from the valence band top to the acceptor is smaller than that of GaN material Ea1, the valence band top of the formed co-doped low acceptor main layer is increased, and the activation energy Ea of the Mg atoms of the acceptor is reduced. Meanwhile, due to the doping of Si atoms, partial filling of deep energy level can be realized, and more Mg atoms are liberated to become free particles.
S33, closing the indium source and the silicon source, introducing the magnesium source, and growing a magnesium doped incorporation layer on the co-doped low acceptor main layer, wherein the magnesium doped incorporation layer is a heavily doped Mg nitride layer, and the doping concentration of Mg is 1E20cm-3-1E21cm-3The growth time is 1s-10 s;
when the Mg atoms are formed on the InN material in step S32, after the processing of the energy bands such as the early stress release and the co-doped low acceptor, the incorporation efficiency and activity of magnesium will be greatly improved, and then the temperature can be raised to continue to grow the non-doped GaN layer in step S31, at this time, the crystal quality will be higher.
S34, repeating the steps S31-S33, forming an undoped nitride layer, a co-doped low acceptor layer and a magnesium doped merging layer in a periodic structure on the P-type nitride front layer, wherein the undoped nitride layer, the co-doped low acceptor layer and the magnesium doped merging layer in a single period are grown in sequence.
When the growing P-type nitride composite layer 400 is a non-nitride-doped layer 401, a co-doped low-acceptor layer 402 and a magnesium-doped merging layer 403 which are cyclically arranged in a multi-period manner, each layer can reduce the Mg atom activation energy of an acceptor, and simultaneously, Si doping of each layer can realize filling of deep energy levels and realize more Mg merging efficiency; and the non-nitride-doped layer 401 is grown by slightly raising the temperature during each cycle, so that the overall crystallization quality is improved.
And S4, finally, introducing nitrogen into the reaction chamber for in-situ annealing activation to form the P-type nitride epitaxial structure with high carrier concentration.
The technical scheme of the invention can also be extended to a method for lifting P-type carriers of other nitride materials such as AlN, the principle is similar to the above, and the process and the effect of the scheme are described by specific embodiments below.
Example 1
In this embodiment, the preparation and testing of the P-type GaN epitaxial structure specifically includes the following steps:
1) growing a U-shaped GaN layer of 2um on a sapphire substrate;
2) growing a 1um P-type GaN front layer on the U-type GaN layer, wherein the doping concentration of Mg is about 1E19cm-3；
3) Setting the growth temperature to 1050 ℃, introducing a gallium source, and growing a non-doped GaN layer for 15 s;
4) closing the gallium source, introducing the indium source and the silicon source, cooling to 950 ℃ to grow the co-doped low acceptor layer for 5s, wherein In/Ga (molar ratio) =2, and the doping concentration of Si is 5E17cm-3；
5) Closing the indium source and the silicon source, only introducing the magnesium source, and growing the Mg doped merging layer for 5s, wherein the Mg doping concentration is 5E20cm-3；
6) Circularly growing for 200 periods according to the steps 3), 4) and 5) to form a P-type GaN composite layer, and keeping the state of introducing ammonia gas in the whole process;
7) and finally, annealing pure N2 in an MOCVD furnace for 10 minutes at 750 ℃ to finish the P-type GaN epitaxial structure sample.
Comparative example 1
This comparative example 1 differs from example 1 in that: the P-type GaN pre-layer was not grown, i.e., step 2) was omitted, and the P-type GaN composite layer was directly grown on the U-type GaN layer, except that the same procedure as in example 1 was repeated.
Comparative example 2
This comparative example 2 differs from example 1 in that: in step 4), only an indium source is introduced, and a silicon source is not introduced, that is, InN without doping Si is grown, and the rest is the same as in example 1.
Comparative example 3
This comparative example 3 differs from example 1 in that: in the step 4), only a silicon source is introduced, and an indium source is not introduced, namely, the non-doped GaN layer is directly doped with Si and then doped with Mg, and the rest is the same as that in the embodiment 1.
Comparative example 4
This comparative example 4 differs from example 1 in that: growing P-type GaN directly using U-type GaN, i.e. directly at 2Growing heavily doped P-type GaN on the U-type GaN layer of um for 20s at 1050 deg.C, wherein the doping concentration of Mg is 5E20cm-3。
Hall effect tests were performed on the P-type GaN epitaxial structure samples prepared in the above example 1 and comparative examples 1 to 4, respectively, under the test condition that the hall current was 1uA, and the obtained ratio of the carrier (hole) concentration of the P-type layer is shown in table 1:
table 1:
| p-type layer | Difference (compare with example 1) | Concentration of carriers |
| Example 1 | / | 6.1E18cm-3 |
| Comparative example 1 | P-free GaN front layer | 2.1E18cm-3 |
| Comparative example 2 | The co-doped layer is only introduced with indium source | 3.2 E18cm-3 |
| Comparative example 3 | Introducing only silicon source into the co-doped layer | 1.0E18cm-3 |
| Comparative example 4 | U-shaped GaN + heavily doped P-shaped GaN | 1.2E17cm-3 |
As can be seen from table 1: 1. the carrier concentration of the P-type layer prepared in the comparative example 1 is reduced compared with that of the P-type layer prepared in the example 1, because the U-type GaN layer has a weak N-type, which affects the subsequent P-type layer, and the subsequent heavily doped Mg can severely affect the stress and the interface state of the epitaxial layer, which affects the Mg incorporation rate of the subsequent highly doped P-type layer, so that the carrier concentration of the finally formed P-type layer is greatly reduced compared with that of the example 1, further, the transition effect of the P-type GaN pre-layer lightly doped with Mg in the example 1 is further explained, the influence of the depletion layer is eliminated, stress release and the interface state are provided for the subsequent highly doped P-type layer, and the incorporation rate of the highly doped P-type Mg and good surface morphology are promoted;
2. the carrier concentration of the P-type layer prepared in comparative example 2 is reduced to some extent compared with that of the P-type layer prepared in example 1, because in comparative example 2, when InN is formed in step 4), Si is not doped, although the forbidden bandwidth of InN is smaller than that of GaN, the valence band is raised, and all the activation energy of Mg atoms of an acceptor is reduced, the incorporation efficiency of Mg is obviously lower than that of example 1, the carrier concentration is reduced, the overall crystallization quality is lower, and therefore, Si doping can partially fill up deep energy levels, more Mg incorporation efficiency is realized, more Mg atoms are released into free particles, and the carrier concentration of the P-type layer is improved;
3. the carrier concentration of the P-type layer prepared in the comparative example 3 is reduced compared with that of the P-type layer prepared in the example 1, because only a silicon source is introduced in the step 4), an indium source is not introduced, namely InN is not formed, heavily doped Mg is incorporated after Si doping is directly carried out on a non-doped GaN layer, and the carrier concentration of the P-type layer is reduced compared with that of the example 1, which shows that although the doping of Si atoms can realize partial filling of deep energy level, more Mg atoms are released to form free particles (the verification result of the comparative example 2), the valence band top of GaN is unchanged, the activation energy of Mg atoms is unchanged, the incorporation efficiency and the activity of Mg are still limited, and the overall crystallization quality is lower than that of the example 1;
4. comparative examples 1 to 3 are lower than the P-type layer prepared in example 1, but they are still higher than the P-type layer in comparative example 4 by an order of magnitude, because comparative example 4 has no P-type GaN pre-layer for transition and no P-type GaN composite layer structure for reducing the acceptor level and increasing the Mg doping activation rate, while comparative example 1 has no transition pre-layer but has a P-type GaN composite layer, which laterally indicates that the P-type GaN composite layer structure has the effect of greatly increasing the P-type carrier layer concentration, and in comparative examples 2 and 3, although the P-type GaN composite layer lacks a doping element, the incorporation efficiency and activity of magnesium are increased due to the action of InN layer and Si atoms, and the carrier concentration is still higher by an order of magnitude than comparative example 4.
Example 2
To further illustrate the effect of the P-type GaN pre-layer in the present invention, the thickness of the P-type GaN pre-layer was changed compared to example 1, and the rest was the same as example 1;
as a result: the hall effect test was performed under test conditions with a hall current of 1 uA:
1) when the thickness of the P-type GaN preposed layer is 0.5um, the doping concentration of Mg is about 1E18cm-3The carrier concentration of the prepared P-type GaN layer is 5.4E18cm-3；
2) When the thickness of the P-type GaN preposed layer is 1.5um, the doping concentration of Mg is about 1E19cm-3The carrier concentration of the prepared P-type GaN layer is 6.2E18cm-3；
The results show that: compared with the P-free GaN pre-layer in the comparative example 1, the pre-layer with 2 thicknesses in the example 2 has improved carrier concentration, and further proves that the P-type GaN pre-layer has a neutralization effect on a depletion layer and a transition effect on stress and an interface state caused by subsequent high doping, and the results of the example 2 and the example 1 jointly show that the neutralization effect and the transition effect are more obvious along with the increase of the thickness of the P-type GaN pre-layer, and the achieved carrier concentration is further improved.
Example 3
To further illustrate the effect of Si doping in the present invention, this example was compared with example 1 with the same change in the doping concentration of Si in the co-doped low acceptor layer as in example 1;
as a result: the hall effect test was performed under a test condition of a hall current of 1 uA:
1) doping concentration of Si in the co-doped low acceptor layer 1E17cm-3Then, the carrier concentration of the prepared P-type GaN layer is 5.3E18cm-3；
2) Doping concentration of Si in the co-doped low acceptor layer 1E18cm-3When the concentration of the carrier of the prepared P-type GaN layer is 4.5E18cm-3。
The results show that: the doping concentration of Si in example 3 is increased compared to the non-doped Si in comparative example 2, which proves that the doping of Si atoms can partially fill the deep level and liberate more Mg atoms into free particles, but the result of example 3 compared to example 1 shows that the doping concentration of Si is too small or too large, which affects the slight decrease of the carrier concentration of the P-type GaN layer, so that the proper doping concentration of Si is required to fill the deep level and match the Mg atoms to liberate the free particles.
Example 4
This embodiment provides a semiconductor device comprising a P-type nitride epitaxial structure as described in any of the above embodiments or examples, wherein the thickness of the P-type GaN composite layer is determined by the number of cycles, and therefore, the thickness can be set according to the requirements of the semiconductor device to be fabricated, such as:
1) the preparation of the GaN-based blue LED requires the thickness of the P-type GaN composite layer to be 100nm, so that the cycle period of the P-type GaN composite layer is set to be 40, and the rest is the same as the scheme in the embodiment 1.
Compared with the traditional method, the prepared GaN-based blue LED adopts U-shaped GaN to grow P-shaped GaN, and the same GaN-based blue LED is prepared on the P-shaped GaN, so that the display brightness is improved by 5%, and the starting voltage is reduced by 0.1V.
2) The PIN device was fabricated requiring a P-type GaN composite layer thickness of 400nm, and thus, the cycle period was set to 200, the rest being the same as in example 1.
Compared with the traditional method, the prepared PIN device directly adopts U-shaped GaN to grow the P-shaped GaN, and the same PIN device is prepared on the P-shaped GaN, so that the response speed is increased by 20%.
The above 1) and 2) further prove that, compared with the preparation method of the comparative example 4, the carrier concentration of the example 1 is greatly improved, the crystallization quality is high, and the related performance of the prepared equivalent product is improved.
The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.
Claims (13)
1. A P-type nitride epitaxial structure is characterized in that: the method comprises the following steps:
a substrate; and
a U-type nitride layer, a P-type nitride front layer and a P-type nitride composite layer sequentially grown on the substrate;
the P-type nitride front layer is a nitride layer lightly doped with Mg;
the P-type nitride composite layer comprises a non-doped nitride layer, a co-doped low-acceptor main layer and a magnesium-doped merging layer which are in a periodic structure, wherein the non-doped nitride layer, the co-doped low-acceptor main layer and the magnesium-doped merging layer in a single period grow sequentially; the magnesium doped incorporation layer is a heavily doped Mg nitride layer;
the co-doped low acceptor main layer is an indium nitride layer doped with Si.
2. A P-type nitride epitaxial structure according to claim 1 wherein: the thickness of the P-type nitride front layer is 0.5um-1.5um, and the doping concentration of Mg in the P-type nitride front layer is 1E18cm-3-1E19cm-3And the doping concentration of Mg in the Mg doping merging layer is greater than that of Mg in the P-type nitride front layer.
3. A P-type nitride epitaxial structure according to claim 1 wherein: the indium nitride layer is doped withThe doping concentration of Si is 1E17cm-3-1E18cm-3。
4. A P-type nitride epitaxial structure according to claim 1 wherein: the doping concentration of Mg doped in the Mg doped incorporation layer is 1E20cm-3-1E21cm-3。
5. A P-type nitride epitaxial structure according to any one of claims 1 to 4, characterized in that: the period of the periodic structure is 20-300.
6. A preparation method of a P-type nitride epitaxial structure is characterized by comprising the following steps: the method comprises the following steps:
s1, growing a U-shaped nitride layer on the substrate;
s2, growing a P-type nitride front layer on the U-type nitride layer, wherein the P-type nitride front layer is lightly doped with Mg;
s3, introducing ammonia gas, and growing a P-type nitride composite layer on the P-type nitride front layer;
s4, introducing nitrogen, annealing and activating to form a P-type nitride epitaxial structure;
wherein, the growing of the P-type nitride composite layer comprises the following steps:
s31, introducing a nitride metal source, and growing a non-nitride-doped layer;
s32, closing the nitride metal source, introducing an indium source and a silicon source, and growing a co-doped low-acceptor main layer on the non-doped nitride layer, wherein the co-doped low-acceptor main layer is an indium nitride layer doped with Si;
s33, closing the indium source and the silicon source, introducing a magnesium source, and growing a magnesium doped merging layer on the co-doped low-acceptor main layer, wherein the magnesium doped merging layer is a heavily-doped Mg nitride layer;
s34, repeating the steps S31-S33, and forming an undoped nitride layer, a co-doped low acceptor main layer and a magnesium-doped merging layer in a periodic structure on the P-type nitride front layer, wherein the undoped nitride layer, the co-doped low acceptor main layer and the magnesium-doped merging layer in a single period are grown in sequence.
7. A method of fabricating a P-type nitride epitaxial structure according to claim 6, characterized in that: the growth thickness of the P-type nitride front layer is 0.5um-1.5um, and the doping concentration of Mg in the P-type nitride front layer is 1E18cm-3-1E19cm-3And the doping concentration of Mg in the Mg doping merging layer is greater than that of Mg in the P-type nitride front layer.
8. A method of fabricating a P-type nitride epitaxial structure according to claim 6, characterized in that: the growth temperature of the P-type nitride composite layer is 900-1050 ℃, wherein the growth temperature of the co-doped low acceptor layer is lower than that of the non-nitride-doped layer.
9. A method of fabricating a P-type nitride epitaxial structure according to claim 6, characterized in that: the growth time of the non-doped nitride layer is 10s-20s, the growth time of the co-doped low-acceptor main layer is 1s-10s, and the growth time of the magnesium-doped incorporation layer is 1s-10 s.
10. A method of fabricating a P-type nitride epitaxial structure according to claim 6, characterized in that: the doping concentration of Si doped in the indium nitride layer is 1E17cm-3-1E18cm-3And the molar ratio of the indium source to the nitride metal source introduced in the step S32 is at least 2.
11. A method of fabricating a P-type nitride epitaxial structure according to claim 6, characterized in that: the doping concentration of Mg in the Mg doping incorporation layer is 1E20cm-3-1E21cm-3。
12. A method of fabricating a P-type nitride epitaxial structure according to one of claims 6 to 11, characterized in that: the number of times of circulating steps S31-S33 in growing the P-type nitride composite layer is 20-300 times.
13. A semiconductor device, characterized in that: comprising a P-type nitride epitaxial structure according to any one of claims 1 to 5.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010018815A (en) * | 1999-08-23 | 2001-03-15 | 윤종용 | A method for fabricating a p-type nitride semiconductor and a manufacturing method using the same |
| CN102097555A (en) * | 2011-01-14 | 2011-06-15 | 武汉迪源光电科技有限公司 | Epitaxial structure of diode |
| CN106463573A (en) * | 2014-05-14 | 2017-02-22 | 南洋理工大学 | Light-emitting device and method of forming the same |
| CN106784184A (en) * | 2016-12-21 | 2017-05-31 | 湘能华磊光电股份有限公司 | LED epitaxial structure of recombination P-type GaN layer and preparation method thereof |
| WO2017088546A1 (en) * | 2015-11-24 | 2017-06-01 | 厦门市三安光电科技有限公司 | Light emitting diode and preparation method therefor |
| EP3460468A2 (en) * | 2017-09-26 | 2019-03-27 | Korea Advanced Nano Fab Center | Gallium nitride-based sensor having heater structure and method of manufacturing the same |
| CN114220889A (en) * | 2021-12-14 | 2022-03-22 | 山西中科潞安紫外光电科技有限公司 | Deep ultraviolet LED epitaxial wafer with vertical structure and growth method thereof |
-
2022
- 2022-04-20 CN CN202210413931.9A patent/CN114512395B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010018815A (en) * | 1999-08-23 | 2001-03-15 | 윤종용 | A method for fabricating a p-type nitride semiconductor and a manufacturing method using the same |
| CN102097555A (en) * | 2011-01-14 | 2011-06-15 | 武汉迪源光电科技有限公司 | Epitaxial structure of diode |
| CN106463573A (en) * | 2014-05-14 | 2017-02-22 | 南洋理工大学 | Light-emitting device and method of forming the same |
| WO2017088546A1 (en) * | 2015-11-24 | 2017-06-01 | 厦门市三安光电科技有限公司 | Light emitting diode and preparation method therefor |
| CN106784184A (en) * | 2016-12-21 | 2017-05-31 | 湘能华磊光电股份有限公司 | LED epitaxial structure of recombination P-type GaN layer and preparation method thereof |
| EP3460468A2 (en) * | 2017-09-26 | 2019-03-27 | Korea Advanced Nano Fab Center | Gallium nitride-based sensor having heater structure and method of manufacturing the same |
| CN114220889A (en) * | 2021-12-14 | 2022-03-22 | 山西中科潞安紫外光电科技有限公司 | Deep ultraviolet LED epitaxial wafer with vertical structure and growth method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 具有侧面柱状结构的高压LED芯片制备;王洪等;《光电子.激光》;20131015(第10期);全文 * |
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