Sapphire Crystal Growing Methods Comparison

Sapphire Crystal Growing Methods Comparison
Growing Method	Advantages	Disadvantages	Application
Kyropoulos	High quality, Large size, High yield, Low cost	Complicate operation, Low consistency, low qualified yield, Not suitable for C sapphire	Rublcon (LED sapphire base)
Czochralski	Production examination easily, Good Shape	High density, iridium gold crucible, High cost, Size restriction	HoneyWell
EFG	High quality	Complicated Equipment and technology	Kyocera
TGT	Simple equipment, easy operation, high yield, C crystal	Uniformity temperature, long period, high cost	Shanghai Institute of Optics and Fine Mechanics
VGF	Simple equipment, high yield	High density	Yunnan, China
VHGF	Crystal size and shape are not restricted	Right is kept in STC	STC
HEM	High quality, large size	High requirement on equipment, complicated techniques, high cost, sapphire easier to break	Crystal System
SAPMAC	Entire crystal, annealing same location, short circle, low cost	Easily influenced by temperature fluctuation	Northeast China

All the above methods to grow sapphire can use tungsten crucible.

More details, please contact sales@chinatungsten.com.

Why Sapphire is Suitable for Infrared Transparent Window

Therefore, the materials for infrared transparent window needs to be high qualified, and should meet the basic requirements as following:
1)High mechanical strength: infrared transparent window material should have sufficient strength, so that it can withstand the high-speed movement of the pressure load.
2) High thermal stability: can withstand the impact of aerodynamic heating and high temperature caused by the change, transmittance and refractive index by the temperature changes.
3) High chemical stability: the material is exposed to the air, so that the material should be able to prevent salt solution or etching gas corrosion, and should not be easy deliquescence
4) High optical transmittance: can efficiently transmit the ultraviolet to the infrared radiation
5) High optical properties: small optical scattering and good refractive index
6) Meet requirement of large size window

Sapphire growing in tungsten crucible, is a wonderful material that can meet all the above requirements. It is suitable for television, infrared imaging and radar. Furthermore, it can meet the high requirement of hypersonic missile wave-transparent. And this is why sapphire has become an excellent choice for high-speed fighter in advanced countries, missiles and other medium wave infrared transparent window material. 

More details, please contact us by email sales@chinatungsten.com. 

Growing Process of Sapphire by Using Tungsten Crucible

The above process shows the process of growing sapphire by using tungsten crucible. CTOMS is mainly producing tungsten crucible for this purpose. If you have got any comment, please feel free to send us email sales@chinatungsten.com.

Sapphire Growth Method - Kyropoulos Method

Kyropoulos method can be shorted as KY method. This method is the first to propose to grow crystals in 1926.later on, it is widely used in the production and research of large-size crystal halogen, hydroxide and carbonate crystals. In 1960s and 1970s, it is improved by former Soviet Union Musatov for the production of sapphire crystals.

The single crystal grown by Kyropoulos method is always shaped like a pear. Its crystal diameter crucible can grow to less than the inner diameter of the small size of 10 ~ 30mm. The principle is similar to Czochralski method. Firstly, heating raw material to the melting point molten metal melt, then a single crystal of the seed (Seed Crystal, also known as seed rod) to contact the molten metal surface, began to grow on the seed crystal and solid-liquid interface and the molten metal single crystal of the same crystal structure seed, seed to a very slow speed pulled up. After then, the seed crystal will be pull up to a height and form a crystal neck, the molten metal solidification rates and stable interface seed, the seed will not pulling up, but nor make the rotation. But only the controlling of the cooling rate of the single crystal is gradually solidified from the top down, and finally solidified into a whole monocrystalline.

This method is applied tungsten crucible as vapor to grow sapphire.

If there is any other question refer to tungsten crucible for sapphire growth furnace, please feel free to contact us through the following methods:
Email:sales@chinatungsten.com
Tel.:+86 592 512 9696
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Sapphire (Growing in Tungsten Crucible) for Laser Host

Sapphire crystal, growing in tungsten crucible, is an excellent laser host materials, such as titanium-doped sapphire crystal is the world's most outstanding broadband tunable laser crystal today, its tunable wavelength range of 660 ~ 1200nm. Moulton was first reported since 1982 to achieve laser oscillation since, because of its very wide tuning range and high gain, etc., which have been widely and well studied. With sapphire optical penetration range is very wide, from near-ultraviolet to mid-infrared light wavelength 0.9nm wavelength 5.5μm have good light transmittance, and within the band of 0.25 ~ 4.5μm is still more than 80% penetration rate; making large size, high integrity sapphire single crystal has been used as the matrix material US LICO (Laser interferometer gravitational observatory) project and other large interferometric device for measuring cosmic gravity waves in the preferred spectral components. Sapphire crystal used in civilian areas has also been very widely, such as in medical equipment, environmental equipment, laser equipment, chemical equipment, high vacuum test equipment, fiber guide wire plate textile industry, bar code scanners to scan window, never wear type Rado watch Mongolia and the like.

If there is any other question refer to molybdenum heating element for sapphire growth furnace, please feel free to contact us through the following methods.

Email: sales@chinatungsten.com
Tel.: +86 592 512 9696/ +86 5925129595
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Main Features for SAPMAC Methods-Sapphire and Tungsten

Main features for SAPMAC Methods, which is sapphire growth method and used tungsten as vector:

1) Put through a cold heart shoulder, to ensure that the large size of the crystal growth process of the crystal to the entire end product of genetic characteristics of a good, good material quality.
2) Through high-precision energy control with micro-pulling, so that no significant thermal disturbance in the whole process of crystal growth, significantly reduced the probability of defect initiation than other methods.
3) Since only trace pulling, reducing the temperature field perturbation. Make more uniform temperature field, so as to ensure the success rate of single crystal growth.

4) Throughout the crystal growth process, the crystal is not made crucible, it is still in the hot zone. It can precisely control the cooling rate, to reduce the thermal stress.
5) Suitable for the growth of large-size crystals, the material is more than 1.2 times the comprehensive utilization Kyropoulos law.
6) Use water as the working fluid within the heat exchanger, the crystal can be achieved in-situ annealing, short test cycle than other methods, and low cost.
7) In the crystal growth process, we can easily observe the growth of crystals.
8) Free surface crystal growth, the crucible is not mandatory, can reduce stress Crystals.
9) Can easily use the desired orientation seed and "necking" process, it helps to relatively fast rate.


If there is any other question refer to tungsten crucible for sapphire growth furnace, please feel free to contact us through the following methods:
Email:sales@chinatungsten.com
Tel.:+86 592 512 9696
Fax:+86 592 512 9797

Sapphire Grow Method- Micro-Pulling And Shoulder Expanding at Cooled Center (SAPMAC)

Micro-pulling and shoulder expanding at cooled center is a sapphire growth method, which is also called micro-pulling rotation Kyropoulos. The is an improved method based on Kyropoulos Method and Pulling Method by Institute of Composite Structures from the Harbin Institute of Technology. It is used to grow large size crystal. Crystal growing system includes control system, vacuum system, heating body, cooling system and thermal protection systems. The following a picture, which is a schematic shoulder cold heart to put the system trace Czochralski method, SAPMAC grown single crystal, the outlook is usually pear-shaped, crystal diameter crucible can grow to more than the inner diameter of the small size of 10 ~ 30mm. The seed is processed into split shape, use seed clips at the bottom of the heat exchanger. Rotating and pulling the heat exchanger can be accomplished seed fixed, crystals, and the exchange interaction between the heat exchanger, crystal and melt.

Tungsten crucible is widely used in sapphire growth furnace, including SAPMAC method.

If there is any other question refer to tungsten crucible for sapphire growth furnace, please feel free to contact us through the following methods:
Email:sales@chinatungsten.com
Tel.:+86 592 512 9696
Fax:+86 592 512 9797