METHOD FOR PREPARING MULTI-LAYER HEXAGONAL BORON NITRIDE FILM

boron nitrideboron nitride

xrd

XRD

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

afm

AFM

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
lateral size of h-BN film	—	h-BN
thickness of h-BN film	—	h-BN
Duration	0.5–2 hours	—
Temperature	2–10 °C	—
Pressure	50–5000 Pa	—
Duration	0.5–8 hours	—
Temperature	0.25–10 °C	—
Temperature	≥ 200 °C	—
Temperature	800–1500 °C	—

Drawings

Patent drawings and their descriptions. Click a drawing to enlarge it.

FIG. 1

FIG. 1 shows a ﬂow chart of a method for preparing a multi-layer hexagonal boron nitride ﬁlm provided by the present disclosure.

FIG. 2

FIG. 2 shows a schematic diagram of a device for preparing a multi-layer hexagonal boron nitride ﬁlm using 35 Fe—B alloy as a boron-containing solid catalyst, …

FIG. 3

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 4

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

FIG. 5

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 6

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

FIG. 7

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

FIG. 8

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 9

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 10

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

FIG. 11

FIG. 11 shows an OM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 12

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 13

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

1 independent · 12 dependent

1
Independentsubstrate (insulating or semiconductor)boron-containing solid catalystnitrogen-containing gas
A method for preparing a multi-layer hexagonal boron nitride ﬁlm, comprising: in a ﬁrst operation, preparing a substrate, the substrate includes an insulating substrate or a semiconductor substrate; in a second operation, preparing a boron-containing solid catalyst, and disposing the boron-containing solid cata-lyst on the substrate; in a third operation, annealing the boron-containing solid catalyst to melt the boron-containing solid catalyst; in a fourth operation, feeding a nitrogen-containing gas and a protecting gas to an atmosphere in which the melted boron-containing solid catalyst resides, the nitrogen-containing gas reacts with the boron-contain-ing solid catalyst to form the multi-layer hexagonal boron nitride ﬁlm on a surface of the substrate, wherein in the third operation, the boron-containing solid catalyst is annealed under a protecting atmosphere and at a normal pressure condition or low pressure condition.
1. 2
  Dependent← claim 1Si₃N₄SiO₂AlNMgOAl₂O₃
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the substrate in the ﬁrst operation comprises a silicon nitride substrate, a silicon oxide substrate, an aluminum nitride substrate, a magnesium oxide substrate, or an aluminum oxide substrate.
2. 3
  Dependent← claim 1Ni-BFe-BPt-BCo-BCr-BFe-Ni-B
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the boron-containing solid catalyst in the second operation comprises at least one of a nickel-boron alloy catalyst, an iron-boron alloy catalyst, a platinum-boron alloy catalyst, and a cobalt-boron alloy catalyst, a chromium-boron alloy catalyst, an iron-nickel-boron alloy catalyst, an iron-boron-silicon alloy catalyst and a nickel-boron-silicon alloy catalyst.
3. 4
  Dependent← claim 1substrate (insulating or semiconductor)boron-containing solid catalyst
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the third operation, placing the substrate and the boron-containing solid catalyst in a closed insulation crucible or a closed semiconductor crucible, placing the crucible in a chemical vapor deposition chamber, and feeding a protecting gas into the chemical vapor deposition chamber.
4. 8
  Dependent← claim 1nitrogen-containing gasNH₃ArH₂
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas comprises nitrogen or ammonia, the protecting gas comprises argon and hydrogen, and a volume ratio of the nitrogen-containing gas to the argon and the hydrogen is 30:1:1 to 1:30:30.
5. 9
  Dependent← claim 1
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas reacts with the boron-containing solid catalyst under a normal pressure condition or low pressure condition, and a reaction time is 0.5-8 hours.
6. 10
  Dependent← claim 1substrate (insulating or semiconductor)
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein after the fourth operation, cooling the substrate with the multi-layer hexagonal boron nitride ﬁlm formed on the surface to room temperature.

Characterization

Measurements and analyses referenced in the patent, with their drawing references.

sem

SEM

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

xrd

XRD

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

afm

AFM

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
lateral size of h-BN film	—	h-BN
thickness of h-BN film	—	h-BN
Duration	0.5–2 hours	—
Temperature	2–10 °C	—
Pressure	50–5000 Pa	—
Duration	0.5–8 hours	—
Temperature	0.25–10 °C	—
Temperature	≥ 200 °C	—
Temperature	800–1500 °C	—

Drawings

Patent drawings and their descriptions. Click a drawing to enlarge it.

FIG. 1

FIG. 1 shows a ﬂow chart of a method for preparing a multi-layer hexagonal boron nitride ﬁlm provided by the present disclosure.

FIG. 2

FIG. 2 shows a schematic diagram of a device for preparing a multi-layer hexagonal boron nitride ﬁlm using 35 Fe—B alloy as a boron-containing solid catalyst, …

FIG. 3

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 4

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

FIG. 5

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 6

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

FIG. 7

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

FIG. 8

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 9

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 10

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

FIG. 11

FIG. 11 shows an OM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 12

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 13

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

1 independent · 12 dependent

1
Independentsubstrate (insulating or semiconductor)boron-containing solid catalystnitrogen-containing gas
A method for preparing a multi-layer hexagonal boron nitride ﬁlm, comprising: in a ﬁrst operation, preparing a substrate, the substrate includes an insulating substrate or a semiconductor substrate; in a second operation, preparing a boron-containing solid catalyst, and disposing the boron-containing solid cata-lyst on the substrate; in a third operation, annealing the boron-containing solid catalyst to melt the boron-containing solid catalyst; in a fourth operation, feeding a nitrogen-containing gas and a protecting gas to an atmosphere in which the melted boron-containing solid catalyst resides, the nitrogen-containing gas reacts with the boron-contain-ing solid catalyst to form the multi-layer hexagonal boron nitride ﬁlm on a surface of the substrate, wherein in the third operation, the boron-containing solid catalyst is annealed under a protecting atmosphere and at a normal pressure condition or low pressure condition.
1. 2
  Dependent← claim 1Si₃N₄SiO₂AlNMgOAl₂O₃
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the substrate in the ﬁrst operation comprises a silicon nitride substrate, a silicon oxide substrate, an aluminum nitride substrate, a magnesium oxide substrate, or an aluminum oxide substrate.
2. 3
  Dependent← claim 1Ni-BFe-BPt-BCo-BCr-BFe-Ni-B
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the boron-containing solid catalyst in the second operation comprises at least one of a nickel-boron alloy catalyst, an iron-boron alloy catalyst, a platinum-boron alloy catalyst, and a cobalt-boron alloy catalyst, a chromium-boron alloy catalyst, an iron-nickel-boron alloy catalyst, an iron-boron-silicon alloy catalyst and a nickel-boron-silicon alloy catalyst.
3. 4
  Dependent← claim 1substrate (insulating or semiconductor)boron-containing solid catalyst
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the third operation, placing the substrate and the boron-containing solid catalyst in a closed insulation crucible or a closed semiconductor crucible, placing the crucible in a chemical vapor deposition chamber, and feeding a protecting gas into the chemical vapor deposition chamber.
4. 8
  Dependent← claim 1nitrogen-containing gasNH₃ArH₂
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas comprises nitrogen or ammonia, the protecting gas comprises argon and hydrogen, and a volume ratio of the nitrogen-containing gas to the argon and the hydrogen is 30:1:1 to 1:30:30.
5. 9
  Dependent← claim 1
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas reacts with the boron-containing solid catalyst under a normal pressure condition or low pressure condition, and a reaction time is 0.5-8 hours.
6. 10
  Dependent← claim 1substrate (insulating or semiconductor)
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein after the fourth operation, cooling the substrate with the multi-layer hexagonal boron nitride ﬁlm formed on the surface to room temperature.

Characterization

Measurements and analyses referenced in the patent, with their drawing references.

sem

SEM

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

xrd

XRD

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

afm

AFM

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
lateral size of h-BN film	—	h-BN
thickness of h-BN film	—	h-BN
Duration	0.5–2 hours	—
Temperature	2–10 °C	—
Pressure	50–5000 Pa	—
Duration	0.5–8 hours	—
Temperature	0.25–10 °C	—
Temperature	≥ 200 °C	—
Temperature	800–1500 °C	—

Drawings

Patent drawings and their descriptions. Click a drawing to enlarge it.

FIG. 1

FIG. 1 shows a ﬂow chart of a method for preparing a multi-layer hexagonal boron nitride ﬁlm provided by the present disclosure.

FIG. 2

FIG. 2 shows a schematic diagram of a device for preparing a multi-layer hexagonal boron nitride ﬁlm using 35 Fe—B alloy as a boron-containing solid catalyst, …

FIG. 3

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 4

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

FIG. 5

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 6

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

FIG. 7

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

FIG. 8

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 9

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 10

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

FIG. 11

FIG. 11 shows an OM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

FIG. 12

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

FIG. 13

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

1 independent · 12 dependent

1
Independentsubstrate (insulating or semiconductor)boron-containing solid catalystnitrogen-containing gas
A method for preparing a multi-layer hexagonal boron nitride ﬁlm, comprising: in a ﬁrst operation, preparing a substrate, the substrate includes an insulating substrate or a semiconductor substrate; in a second operation, preparing a boron-containing solid catalyst, and disposing the boron-containing solid cata-lyst on the substrate; in a third operation, annealing the boron-containing solid catalyst to melt the boron-containing solid catalyst; in a fourth operation, feeding a nitrogen-containing gas and a protecting gas to an atmosphere in which the melted boron-containing solid catalyst resides, the nitrogen-containing gas reacts with the boron-contain-ing solid catalyst to form the multi-layer hexagonal boron nitride ﬁlm on a surface of the substrate, wherein in the third operation, the boron-containing solid catalyst is annealed under a protecting atmosphere and at a normal pressure condition or low pressure condition.
1. 2
  Dependent← claim 1Si₃N₄SiO₂AlNMgOAl₂O₃
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the substrate in the ﬁrst operation comprises a silicon nitride substrate, a silicon oxide substrate, an aluminum nitride substrate, a magnesium oxide substrate, or an aluminum oxide substrate.
2. 3
  Dependent← claim 1Ni-BFe-BPt-BCo-BCr-BFe-Ni-B
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein the boron-containing solid catalyst in the second operation comprises at least one of a nickel-boron alloy catalyst, an iron-boron alloy catalyst, a platinum-boron alloy catalyst, and a cobalt-boron alloy catalyst, a chromium-boron alloy catalyst, an iron-nickel-boron alloy catalyst, an iron-boron-silicon alloy catalyst and a nickel-boron-silicon alloy catalyst.
3. 4
  Dependent← claim 1substrate (insulating or semiconductor)boron-containing solid catalyst
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the third operation, placing the substrate and the boron-containing solid catalyst in a closed insulation crucible or a closed semiconductor crucible, placing the crucible in a chemical vapor deposition chamber, and feeding a protecting gas into the chemical vapor deposition chamber.
4. 8
  Dependent← claim 1nitrogen-containing gasNH₃ArH₂
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas comprises nitrogen or ammonia, the protecting gas comprises argon and hydrogen, and a volume ratio of the nitrogen-containing gas to the argon and the hydrogen is 30:1:1 to 1:30:30.
5. 9
  Dependent← claim 1
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein in the fourth operation, the nitrogen-containing gas reacts with the boron-containing solid catalyst under a normal pressure condition or low pressure condition, and a reaction time is 0.5-8 hours.
6. 10
  Dependent← claim 1substrate (insulating or semiconductor)
  The method for preparing a multi-layer hexagonal boron nitride ﬁlm according to claim 1, wherein after the fourth operation, cooling the substrate with the multi-layer hexagonal boron nitride ﬁlm formed on the surface to room temperature.

Characterization

Measurements and analyses referenced in the patent, with their drawing references.

sem

SEM

FIG. 3 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

xrd

XRD

FIG. 4 shows an XRD spectrum of a multi-layer hexago- nal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 5 shows a TEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

tem

TEM

FIG. 6 shows a nano-beam electron diffraction image of 50 a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 7 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a 55 multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 8 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 9 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm according …

Figure references

boron nitrideboron nitride

afm

AFM

FIG. 10 shows an AFM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a B₂ multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

raman spectroscopy

Raman Spectroscopy

FIG. 12 shows a Raman spectrum of a multi-layer hex- agonal boron nitride ﬁlm prepared by the method for pre- paring a multi-layer hexagonal boron nitride ﬁlm …

Figure references

boron nitrideboron nitride

sem

SEM

FIG. 13 shows an SEM image of a multi-layer hexagonal boron nitride ﬁlm prepared by the method for preparing a multi-layer hexagonal boron nitride ﬁlm …

Figure references