WO2023029620A1 - Organomagnesium compound and electronic device - Google Patents

Abstract

The present application provides an organomagnesium compound having a structure represented by the following structural formula (1): the organomagnesium compound is a liquid in a working state, has a stable high saturation vapor pressure, and is very suitable as a magnesium dopant source for semiconductor doping; in a magnesium source process, magnesium components are evenly distributed, which improves epitaxy uniformity and production process stability, and is suitable for large-scale substrate epitaxy; in addition, the vapor pressure is also very stable at the end of the use of the magnesium source, which improves use efficiency and gallium production rate, reduces production costs, and is suitable for mass production.

Description

Organomagnesium compounds and electronic devices technical field

The present application relates to the field of metal organic compounds, in particular to an organomagnesium compound and an electronic device.

Background technique

The third-generation semiconductor materials are mainly gallium nitride and silicon carbide. The production process is divided into three major steps: single crystal growth, epitaxial layer growth and device manufacturing, corresponding to the industrial chain substrate, epitaxy, devices and modules. link.

Epitaxy is the core intermediate link of the entire industrial chain. The epitaxy process technology directly affects the performance of the device and plays a very critical role in the development of the industry. The metal organic compound is the key supporting raw material for the epitaxy technology. The purity and vapor pressure of the metal organic compound The stability directly determines the performance of the device, so the technical development of metal organic compounds plays a key role in the development of the industry.

Magnesium is usually used as a dopant in the epitaxial growth of P-type GaN technology. Magnesocene is the most commonly used source of magnesium. Its melting point is greater than 170 ° C. It is a colorless crystal at normal temperature and pressure. As a solid source, Magnesocene There are many limitations, for example, due to the small surface area of the product particles, and "channeling" is easy to occur in the steel cylinder used, resulting in unstable vapor pressure, uneven doping concentration of magnesium in the prepared chip, and the usage rate of magnesium dicene is lower than 20%.

Solid-state magnesocene has been unable to meet the needs of the existing process for the large flow of magnesium source steam. In order to solve this problem, the prior art generally optimizes the substituents on the magnesocene ring or the form of the magnesocene, such as Chinese patent literature (application publication number: CN112004959A, application publication date: November 27, 2020) A magnesium compound suitable for atomic layer deposition, the magnesium compound maintains the overall structure of magnesiumocene, and at the same time replaces a hydrogen atom on the magnesiumocene ring with isopropyl, sec-butyl or tert-butyl, but the Magnesium compounds are only suitable for atomic layer deposition. Chinese patent literature (application publication number: CN1399006A, application publication date: February 26, 2003) discloses a preparation method of a solution magnesium source, which disperses magnesium dicene or dimethyl magnesium dicene in a solvent, A high-concentration solution magnesium source is formed to replace solid-state magnesiumocene, but this method inevitably introduces solvents that interfere with the epitaxy process.

Therefore, the development of magnesium sources with stable high saturated vapor pressure and high utilization rate is of great significance to the manufacture of semiconductor devices.

Contents of the invention

The present application provides an organomagnesium compound with a novel structure, and the organomagnesium compound has stable high saturated vapor pressure and high usage rate.

On the one hand, the present application provides an organomagnesium compound, which has a structure represented by the following structural formula (1):

Another aspect of the present application provides an electronic device, comprising an epitaxial layer doped with magnesium atoms provided by the organomagnesium compound represented by structural formula (1).

In one embodiment, the epitaxial layer is an Al _a In _b Ga _1-ab N layer, wherein, 0≤a≤1, 0≤b≤1, 0≤a+b≤1, and a value and b value be constant, linear or nonlinear.

In one embodiment, the doping concentration of the Al _a In _b Ga _1-ab N layer is between 1×10 ¹⁸ cells/cm ³ and 5×10 ²⁰ cells/cm ³ .

In one embodiment, the electronic device is a light emitting diode, a transistor, a laser, a detector or a solar cell.

Beneficial effects: In this application, the organomagnesium compound is in a liquid state in the working state, has a stable high saturated vapor pressure, and is very suitable as a magnesium source dopant for semiconductor doping; the magnesium component is evenly distributed in the magnesium source process, improving It improves the epitaxial uniformity and production process stability, and is suitable for large-scale substrate epitaxy; on the other hand, the vapor pressure at the end of the magnesium source is also very stable, thereby improving the use efficiency and production efficiency of gallium, reducing production costs, and suitable for large-scale Mass production of electronic devices.

Description of drawings

Hereinafter, some specific embodiments of the present application will be described in detail in an exemplary and non-restrictive manner with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals indicate the same or similar components or parts. Those skilled in the art should understand that, The drawings are not necessarily drawn to scale. In the attached picture:

FIG. 1 is a schematic structural view of a light-emitting diode epitaxial wafer prepared in Example 1.

Detailed ways

In order to make the above-mentioned purposes, features and advantages of the present application more obvious and understandable, many specific details are set forth in the following description so as to fully understand the present application, but the present application can be implemented in many other ways that are different from those described here , those skilled in the art can make similar improvements without departing from the connotation of the present application, so the present application is not limited by the specific implementation disclosed below.

The application provides an organomagnesium compound, which has a structure shown in the following structural formula (1):

For ease of understanding and description, the carbon atoms in the structural formula (1) are labeled, and the carbon atoms in the three methylcyclopentadiene structures are respectively marked as symbols 1, 2, 3, 4, 5 and 6, and the symbols 1', 2', 3', 4', 5' and 6', marked 1", 2", 3", 4", 5" and 6".

The organomagnesium compound shown in the above structural formula (1) has never been reported in the prior art. As can be seen from the specific structural formula, the organomagnesium compound is composed of two magnesium atoms and three methylcyclopentadiene groups. It is completely different from the structure of the existing magnesium dicene, methyl magnesium dicene or ethyl magnesium dicene. Specifically, the core part of the structural formula of the organomagnesium compound is formed by combining two magnesium atoms and three cyclopentadiene groups, wherein the two cyclopentadiene groups are directly connected, and are respectively connected to Another cyclopentadiene group is connected; and in the prior art, organomagnesium compounds such as methyl dimagnesium or ethyl dimagnesium etc. are all on the basis of maintaining the dimagnesium core structure, and increase Substituents such as methyl, ethyl, etc.

The organomagnesium compound of the present application is in a liquid state under working conditions, has a stable high saturated vapor pressure, and is very suitable as a magnesium source dopant for semiconductor doping; the magnesium component is evenly distributed in the magnesium source process, which improves the uniformity of epitaxy And production process stability, suitable for large-scale substrate epitaxy; on the other hand, the vapor pressure at the end of the magnesium source is also very stable, thereby improving the use efficiency and production efficiency of gallium, reducing production costs, suitable for large-scale mass production.

The preparation process of the organomagnesium compound shown in structural formula (1) is as follows:

In an anhydrous and oxygen-free glove box, add 98g of high-purity magnesium chips into a cylindrical quartz synthesis column with a heating wire, the magnesium chips are supported by the baffle in the synthesis column, and the synthesis column is placed vertically; above the synthesis column, A 500ml constant pressure funnel with a stopcock is connected, and 500ml of methylcyclopentadiene monomer is added to the funnel, and the upper port of the funnel is connected to an argon cylinder; below the synthesis column, a 2000ml two-necked flask is connected, and the remaining ports of the flask are connected to a serpentine Condenser, the cooling liquid is set at 32°C, and the upper port of the condenser is connected to the tail gas absorption device; the synthesis device is purged with an air flow of 5 L/min to replace the nitrogen in the synthesis device, and the purging time is 30 minutes. After the purging is completed, the air flow is adjusted to The bubbler bubbles at a constant speed of 1 bubble per second; the voltage of the heating wire is controlled by a voltage regulator, and the temperature of the synthesis column is controlled at about 540°C through a thermocouple, and it is stable for 30 minutes; dripping at a speed of 1 drop per second Methylcyclopentadiene monomer, the mist that occurs in the receiving bottle is cooled by a condenser into the receiving bottle, and finally 360g of the reaction solution can be obtained; the reaction solution is concentrated by an atmospheric simple distillation device to obtain a crude product concentrate; Build a vacuum rectification device, put the concentrated crude product into the kettle of the rectification device, and purify the crude product by vacuum distillation under the absolute pressure of 0.1 kPa. The top temperature of the collection is between 58-63 °C Between the distillates, liquid organomagnesium compounds were obtained with a yield of about 60%.

It is determined that the melting point of the liquid organomagnesium compound is between 28-31° C., and the solidified state is a colorless and transparent crystal.

As detected by ¹ H NMR (proton nuclear magnetic resonance spectrum), the liquid organomagnesium compound obtained above does not contain organic impurities, and the organic content of the obtained liquid organomagnesium compound is above 99.9%.

Through the full element detection of ICP-OES (inductively coupled plasma optical emission spectrometer), the content of all inorganic impurities in the liquid organomagnesium compound is less than 1ppm, and the silicon impurity content is about 0.2ppm. The purity of the liquid organomagnesium compound is as high as 99.9999%. Raw material usage requirements in the semiconductor industry.

Characterizing the liquid organomagnesium compound can confirm the specific structure of the liquid organomagnesium compound.

The specific means for characterizing the liquid organomagnesium compound include ¹ H NMR (proton nuclear magnetic resonance spectrum), COZY-NMR (two-dimensional nuclear magnetic resonance correlation spectrum), HSQC-NMR (nuclear magnetic resonance heteronuclear single quantum correlation spectrum), HMBC ( heteronuclear carbon-hydrogen correlation spectrum), ¹³ C-NMR (carbon nuclear magnetic resonance spectrum) and GC-MS (gas chromatography-mass spectrometry).

The characterization results are as follows:

Characterization results of ¹ H NMR, ¹ H NMR (400MHz, C ₆ D ₆ ): δ=6.06 (1H, s, H2), 5.93 (4H, dd, J=2.69Hz, H2', H2", H4', H4"), 5.80 (4H, dd, J=2.70Hz, H4, H5, H5', H5"), 2.07 (9H, s, H6, H6', H6");

According to the characterization results of COZY-NMR, the 2.07ppm peak (H6, H6', H6") is coupled with the 5.80ppm peak (H4, H5, H5', H5"), and the 5.80ppm peak is coupled with the 5.93ppm peak (H2', H2" , H4', H4") there is coupling;

HSQC-NMR characterization results, 2.07ppm peak and 13.48ppm peak (C6, C6', C6") are coupled, 5.80ppm peak (H4, H5, H5', H5") and 106.7ppm peak (C4, C5, C5 ', C5"), 5.93ppm peak (H2', H2", H4', H4") coupled with 105.9ppm peak (C2', C2", C4', C4"), 6.06ppm peak (H2) There is coupling with the 107.1ppm peak (C2);

Characterization results of HMBC, 5.80ppm peaks (H4, H5, H5', H5") and 5.93ppm peaks (H2', H2", H4', H4") and 119.1ppm peaks (C1, C1', C2", C3', C3") and 118.9ppm peak (C3) remote coupling;

Characterization results of ¹³ C-NMR, ¹³ C NMR (125 MHz, C ₆ D ₆ ): δ=119.1 (C1, C1', C2", C3', C3"), 118.9 (C3), 107.1 (C2), 106.7 (C4, C5, C5', C5"), 105.9 (C2', C2", C4', C4"), 13.48 (C6, C6', C6");

Characterization results of GC-MS, GC-MS (EI+): 281.2 [MH]+, calculated value C ₁₈ H ₁₇ Mg ₂ : 281.1; %Mg(ICP-OES): 17.20%, calculated value: 17.20%.

Based on the above characterization and analysis of the liquid organomagnesium compound, it can be confirmed that the liquid organomagnesium compound has a structure represented by structural formula (1).

The following are application cases of organomagnesium compounds shown in structural formula (1):

Example 1

Adopt the organomagnesium compound shown in structural formula (1) as dopant to prepare the epitaxial wafer of light-emitting diode:

1) Put the sapphire substrate on the carrier plate in the MOCVD reaction chamber, grow a 25nm buffer layer at a temperature of 540°C and a growth pressure of 300torr, where the buffer layer is a low-temperature GaN buffer layer, and the Ga source required for growth is TMG Source (trimethylgallium), the growth atmosphere is _H atmosphere;

2) On the buffer layer, grow a 2.5 μm unintentionally doped nitride layer at a temperature of 1080°C and a growth pressure of 200torr, wherein the unintentionally doped nitride layer is an unintentionally doped GaN layer, and the required Ga The source is TMG source, and the growth atmosphere is _H2 atmosphere;

3) On the unintentionally doped nitride layer, grow a 2.5μm N-type nitride layer at a temperature of 1060°C and a growth pressure of 200torr, wherein the N-type nitride layer is an N-GaN layer, and the doping concentration of Si is 8×10 ¹⁸ cells/cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is H ₂ atmosphere;

4) On the N-type nitride layer, grow a nitride light-emitting layer under the conditions of a temperature of 750°C and a growth pressure of 250torr, wherein the nitride light-emitting layer is 9 pairs of InGaN/GaN quantum well light-emitting layers that are periodically and repeatedly grown, and the InGaN well The thickness of the layer is 3nm, the growth temperature is 750°C, the growth atmosphere is switched to _N2 atmosphere, the thickness of the GaN barrier layer is 11nm, the growth temperature is 810°C, the growth atmosphere is switched to _H2 atmosphere, and the Ga source required for growth is TEG (triethylgallium), the In source is TMIn (trimethylindium);

5) On the N-type nitride layer, grow a 40nm P-type nitride insertion layer at a temperature of 770°C and a growth pressure of 200torr, wherein the P-type nitride insertion layer is a P-GaN layer, as shown in the structural formula (1) The organomagnesium compound is used as dopant, the doping concentration of magnesium is 5×10 ¹⁹ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is N ₂ atmosphere.

6) On the P-type nitride insertion layer, grow a 25nm P-type nitride electron blocking layer at a temperature of 970° C. and a growth pressure of 200 torr, wherein the P-type nitride electron blocking layer is a P-type AlGaN layer, and the structural formula (1 ) as a dopant, the doping concentration of magnesium is 1.5×10 ²⁰ /cm ³ , the Ga source required for growth is TMG source, the Al source is TMAl (trimethylaluminum), and the growth atmosphere is _N2 atmosphere.

7) On the P-type nitride electron blocking layer, grow a P-type nitride hole layer of 50 nm under the conditions of a temperature of 970 ° C and a growth pressure of 200 torr, wherein the P-type nitride hole layer is a P-type GaN layer, and the structural formula ( 1) The organomagnesium compound shown as the dopant is used as the dopant, the magnesium doping concentration is 5×10 ¹⁹ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is switched to H ₂ atmosphere.

8) On the P-type nitride hole layer, grow a 3nm P-type nitride contact layer at a temperature of 790°C and a growth pressure of 200torr, wherein the P-type nitride contact layer is a P-type InGaN layer, and the structural formula (1) The organic magnesium compound shown is used as a dopant, the magnesium doping concentration is 2×10 ²⁰ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is switched to N ₂ atmosphere.

Fig. 1 shows the structure diagram of the light-emitting diode epitaxial wafer prepared in Example 1, which includes a sapphire substrate 1, a low-temperature GaN buffer layer 2, an unintentionally doped GaN layer 3, an N-GaN layer 4, and an InGaN/ GaN quantum well light-emitting layer 5 and multi-quantum well structure 6, wherein the multi-quantum well structure 6 includes: P-type nitride insertion layer 61, P-type nitride electron blocking layer 62, P-type nitride hole layer 63 and P-type Nitride contact layer 64 .

Comparative example 1

Epitaxial wafers of light-emitting diodes were prepared using magnesium dicene as a dopant:

The preparation process of the epitaxial wafer of the light-emitting diode in Comparative Example 1 is substantially the same as in Example 1, the difference is that solid-state magnesium dicene is used as the magnesium source dopant, and the specific preparation process is as follows:

1) Put the sapphire substrate on the carrier plate in the MOCVD reaction chamber, grow a 25nm buffer layer at a temperature of 540°C and a growth pressure of 300torr, where the buffer layer is a low-temperature GaN buffer layer, and the Ga source required for growth is TMG Source (trimethylgallium), the growth atmosphere is _H atmosphere;

2) On the buffer layer, grow a 2.5 μm unintentionally doped nitride layer at a temperature of 1080°C and a growth pressure of 200torr, wherein the unintentionally doped nitride layer is an unintentionally doped GaN layer, and the required Ga The source is TMG source, and the growth atmosphere is _H2 atmosphere;

3) On the unintentionally doped nitride layer, grow a 2.5μm N-type nitride layer at a temperature of 1060°C and a growth pressure of 200torr, wherein the N-type nitride layer is an N-GaN layer, and the doping concentration of Si is 8×10 ¹⁸ cells/cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is H ₂ atmosphere;

4) On the N-type nitride layer, grow a nitride light-emitting layer under the conditions of a temperature of 750°C and a growth pressure of 250torr, wherein the nitride light-emitting layer is 9 pairs of InGaN/GaN quantum well light-emitting layers that are periodically and repeatedly grown, and the InGaN well The thickness of the layer is 3nm, the growth temperature is 750°C, the growth atmosphere is switched to _N2 atmosphere, the thickness of the GaN barrier layer is 11nm, the growth temperature is 810°C, the growth atmosphere is switched to _H2 atmosphere, and the Ga source required for growth is TEG (triethylgallium), the In source is TMIn (trimethylindium);

5) On the N-type nitride layer, grow a 40nm P-type nitride insertion layer under the conditions of a temperature of 770°C and a growth pressure of 200torr, wherein the P-type nitride insertion layer is a P-GaN layer, doped with magnesium dicene agent, the doping concentration of magnesium is 5×10 ¹⁹ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is N ₂ atmosphere.

6) On the P-type nitride insertion layer, grow a 25nm P-type nitride electron blocking layer under the conditions of a temperature of 970°C and a growth pressure of 200torr, wherein the P-type nitride electron blocking layer is a P-type AlGaN layer, a magnesium dicene As a dopant, the doping concentration of magnesium is 1.5×10 ²⁰ /cm ³ , the Ga source required for growth is TMG source, the Al source is TMAl (trimethylaluminum), and the growth atmosphere is N ₂ atmosphere.

7) On the P-type nitride electron blocking layer, grow a P-type nitride hole layer of 50nm under the conditions of a temperature of 970°C and a growth pressure of 200torr, wherein the P-type nitride hole layer is a P-type GaN layer. Magnesium is used as a dopant, the magnesium doping concentration is 5×10 ¹⁹ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is switched to H ₂ atmosphere.

8) On the P-type nitride hole layer, grow a 3nm P-type nitride contact layer at a temperature of 790°C and a growth pressure of 200torr, wherein the P-type nitride contact layer is a p-type InGaN layer, made of dichloromagnesium Dopant, magnesium doping concentration is 2×10 ²⁰ /cm ³ , the Ga source required for growth is TMG source, and the growth atmosphere is switched to N ₂ atmosphere.

The luminance of the furnace outer ring of the light-emitting diode of the epitaxial wafer prepared based on different magnesium source dopants in Example 1 and Comparative Example 1 is measured, and it is found that both luminance curves are basically in the luminous wavelength range between 450-470 nanometers. Keep consistent, the maximum brightness is around 455 nanometers, and the maximum brightness value is about 300mW, which proves that the doping effect of the device prepared when using the organomagnesium compound shown in the structural formula (1) and the magnesium dicene as the dopant is equivalent.

Compared with when magnesium dicene is used as a dopant, in the case of keeping the brightness of the device equivalent, since the organomagnesium compound shown in the structural formula (1) is liquid in the working state, it has a more stable high saturation vapor pressure, and the magnesium group The distribution is uniform, and the vapor pressure is more stable at the end of the use of the magnesium source, thereby improving the use efficiency and production efficiency of gallium, reducing production costs, lower requirements on the process, and suitable for mass production of devices.

In addition, except that the organic magnesium compound shown in structural formula (1) is applied to the epitaxial layer of light-emitting diodes, other electronic devices such as transistors, lasers, detectors or solar cells all involve magnesium-doped epitaxial layers, and the epitaxial layers of these epitaxial layers Magnesium doping can also use organomagnesium compounds in this application as dopants.

So far, those skilled in the art should recognize that, although a number of exemplary embodiments of the present application have been shown and described in detail herein, without departing from the spirit and scope of the present application, the The content directly determines or derives many other variations or modifications consistent with the principles of the application. Accordingly, the scope of this application should be understood and deemed to cover all such other variations or modifications.

Claims (5)

1. An organomagnesium compound, characterized in that it has a structure represented by the following structural formula (1):

   
2. An electronic device comprising an epitaxial layer doped with magnesium atoms, characterized in that the magnesium atoms are provided by the organomagnesium compound according to claim 1.
3. The electronic device according to claim 2, wherein the epitaxial layer is an Al _a In _b Ga _1-ab N layer, wherein, 0≤a≤1, 0≤b≤1, 0≤a+b≤ 1, and the values of a and b are constant, change linearly or nonlinearly.
4. The electronic device according to claim 3, characterized in that the doping concentration of magnesium atoms in the Al _a In _b Ga _1-ab N layer is 1×10 ¹⁸ /cm ³ to 5×10 ²⁰ /cm between ³ .
5. The electronic device according to claim 2, wherein the electronic device is a light emitting diode, a transistor, a laser, a detector or a solar cell.

Images