Synthesis way of large particles diamond
single crystal seed crystal; (2) the epitaxial growth method is adopted to
produce large single crystal diamond. Synthesis approach to large particles
diamond single crystal seed crystal, even though it has about 6 mm of massive
domestic single crystal, you will find 10 mm or study plan, but it's rare on
the market. While Japan's sumitomo corporation available synthetic diamond
single crystal diamond tool adopted the larger particles.
Epitaxial growth strategy is employed to
develop large single crystal diamond, should cause our great attention. Many
people believe that the epitaxial growth cannot obtain diamond single crystal,
but also in natural crystal growth is a phenomenon, you start with a great deal
of small crystal bud, spent my youth within a basement, crystal sprouts grow up
step by step, gradually lessen the crystal quantity. We label this phenomenon
"geometric elimination law", we can use this to spell out the truth
that may develop into single crystal diamond thin film.
Cubic boron nitride composite and its
progression of functional materials
The actual domestic research and production
of cubic boron nitride composite strength is very weak, research institutes and
universities are limited in several, is 1 ~ 2 production enterprises. The
initial thinking about cubic boron nitride should are the cause of 25% ~ 30% of
superhard material, after decades of development also taken into account only
5% ~ 5%, it is really an unreasonable phenomenon. Not forgetting its composite
functional materials originated.
A, cubic boron nitride composite sheet of
limited to henan a business, its diameter is ф (30 ~ 35) mm, we've got the
technology must be further improved, mainly the uniformity, stability, if can
industrialization, becasue it is development prospect is going to be
considerable.
B, cubic boron nitride functional research
domestic visible should show up at jilin university. To date on the planet rich
in temperature and pressure method in laboratory within the condition of
maximum height and width of the synthesis of cubic boron nitride single crystal
is simply 3 mm. Especially a lot of the development of the crystal shape is
irregular, unfit for device research applications. With this, the researchers
conducted an operating device rich in purity flake synthesis, cubic boron
nitride single crystal is obtained nearly millimeter level surface with optical
flatness, shape rules of high purity flake cubic boron nitride single crystal.
Even as we have laid the inspiration for your further study its properties.
Cubic boron nitride crystal is really a
typical Ⅲ - V compound, its resistivity is 1010 Ω. Cm, 13
w/cm. The thermal conductivity K, can tolerate high temperature of 1200 ° C, and have
the most wide direct band gap of 6.4 eV, so also is a kind of extremely important
excellent semiconductor material, it in temperature and also power broadband
device microelectronics features a broad application prospect. Cubic boron
nitride with sphalerite structure, is among the macroscopic symmetry F43m - Td
group, also can use a second order nonlinear optical effect. It can be used to
make optical higher harmonic generator, electro-optic modulator, visible and
ultraviolet light converter, optical rectifier, optical parametric amplifier
and so forth. Cubic boron nitride as diamond is still equipped with a solid
ability to resist radiation, on the preparation of radiation devices.
Therefore, the preparation of cubic boron nitride materials research towards
the national economy in several fields, mainly in the aerospace, military and
also other harsh environmental conditions application breakthrough device has
important practical significance.
As a result of sheet, the synthesis of
cubic boron nitride crystal provided can be used as the properties of crystal
material, make us from the study of nature of cubic boron nitride is incredibly
apparent success. For instance, together with the progression of lamellar cubic
boron carbide, then can be acquired with diamond CVD method will take care of
the ideal semiconductor devices. Hence the functional sex in the cubic boron
nitride research becomes the greater important!
In the above content, there exists a lot of
work needs to be carried out in superhard materials. We very often say that the
Modern is the century of diamond, it's not just within the development and use
of abrasive, more could be the development and using functional. Our country
carries a good study atmosphere, using a large numbers of new and old combined
with continuing development of technology and science talents. We totally
believe in the long run comprehensive catch up with and surpass the advanced
world level.