Sapphire ky crystallization furnace kyropoulos foam process Large
size crystal growth equipment for LED substrate
Kyropoulos bubble method (Ky method for short) is a melt growth
method by dipping seed crystals into molten sapphire melt and
taking them out at a controlled rate when the crucible and crystal
are reversed, repeatedly adding layers to form crystals. This
method can grow high quality, low defect density, large size
sapphire crystal, and is widely used in LED substrate and other
fields.
Technical Parameter
| Melting amount: | ≥200kg |
| Furnace cavity height: | Φ800×1200mm |
| Single crystal pulling speed range: | 0.1 ~ 20mm/h stepless speed regulation |
| Fast rise/fall of seed crystal: | 0-150mm/min stepless speed regulation |
| Seed speed range: | 1 ~ 20r/min stepless speed regulation |
| Maximum lifting stroke of seed crystal shaft: | 400mm |
| Heater power: | 120KW |
| Maximum heating temperature: | 2100℃ |
| Power supply (incoming line) : | 3-phase 380V |
| Output working current: | 0-10000A DC |
| Output working voltage: | 0-12.5V DC |
| Maximum height of the host: | 2800mm |
| Limit vacuum of furnace chamber: | ≤6.7×10-3 Pa |
| Double load cell: | 100Kg(single) |
| Weight: | about 1500Kg |
| Machine weight: | about 2000Kg |
| Main machine area: | 3800×2100mm |
| The machine covers an area of: | 4000×3100mm |
| Inlet pressure: | 0.3MPa±0.02MPa |
| Water inlet temperature: | 20 ~ 25℃ |
Working principle
The core of Kyropoulos method lies in thermal field design and seed
control. By heating the high purity aluminum oxide raw material in
the crucible, the equipment makes it melt and forms a temperature
distribution mode of high temperature in the upper part and low
temperature in the lower part. The seed crystals grow from the
center of the melt surface, with the seed crystals as the core, and
the melt crystallizes layer by layer from the crucible to the
crystal wall, finally forming a single crystal.
Product structure and characteristics
1. Thermal field design: including crucible, thermal protection layer, upper seed heat
exchanger and crucible support body, etc., to ensure uniform
crystallization of melt.
2. Seed crystal control: By precisely controlling the temperature gradient and pulling
speed of the seed crystal, high-quality crystal growth is achieved.
3. Automation system: Modern equipment is usually equipped with automatic planting
system and automatic control system, which can produce efficiently.
Technological advantage
1. High-quality crystal: Ky method can grow low defect density, large size sapphire
crystal, to meet the LED industry's demand for high-quality
substrate.
2. Relatively low cost: Compared with other methods (such as Czochralski method), Ky
method has low operational complexity and relatively controllable
cost.
3. Technological innovation: The improved Ky method (IKY) further improves the crystal yield
and reduces the production cost by optimizing the seed and neck
pulling technology.
Machine application
Kyropoulos bubble process equipment is widely used in the following
fields:
1. LED industry: Used to produce high-quality sapphire substrate to meet the needs
of LED chip manufacturing.
2. Infrared military devices: Sapphire is widely used in infrared window materials because of
its excellent optical properties.
3. Satellite space technology: Sapphire is used as a key material in satellite technology.
4. Laser window material: Used for high-performance laser window material.
Kyropoulos crystal growth equipment with its high efficiency, low
cost and high quality, in the field of sapphire crystal growth
occupies an important position, and is widely used in many
high-tech fields.
FAQ
1. Q: What are the core advantages of sapphire crystallization
furnace (Kyropoulos blister method) compared with other crystal
growth methods?
A: 1. No need to continuously pull the seed crystal: in the equal
diameter growth stage, the crystal is crystallized by natural
cooling, without relying on mechanical lifting, reducing mechanical
disturbances and defects.
2. Suitable for large size crystals: it can grow 85-120 kg sapphire
single crystal to meet industrial mass production needs, such as
LED substrate and optical window applications.
3. High yield and low defect: Optimized thermal field design (such
as segmented heaters and multi-layer heat shield), reduce
dislocation density (<1000/cm²), and yield more than 75%.
4. Energy saving and automation: fully enclosed vacuum chamber and
double-layer water cooling structure reduce energy loss, combined
with PLC control system to achieve automated operation and reduce
manual intervention.
2. Q: What is the essential difference between the working
principle of the bubble method equipment and the traditional
lifting method (such as Czochralski method)?
A: 1. Growth stage difference: lifting method: the whole process
needs to mechanically lift the seed crystal, and crystal growth is
achieved by controlling the lifting speed, which is easy to cause
defects due to mechanical vibration. Bubble growth method: only in
the necking stage to pull the seed crystal, the equal diameter
stage depends on the temperature gradient natural growth, reduce
stress and improve crystal uniformity.
2. Thermal field control: The bubble growth method adopts dual
temperature zone independent heating (side heating body + bottom
heating body), accurately regulates axial and radial temperature
gradients, and prevents bubbles and cracks. The lifting rule relies
on a single heating source, and the temperature gradient is fixed,
which is difficult to adapt to the growth of large crystals.
3. Application scenario: The bubble method is more suitable for
large size, high purity crystals (such as sapphire, calcium
fluoride), while the Tila method is mostly used for silicon,
germanium and other conventional semiconductor materials.
Tag: #Sapphire crystal furnace, #Kyropoulos bubble growth method,
#Ky growth equipment, #Sapphire crystal production, #Sapphire
wafer, #Large size crystal growth equipment, #LED substrate
