High purity heat-resistant quartz crucible

In semiconductor, photovoltaic, optical coating, and laboratory high-temperature processes, the purity and heat resistance of crucibles directly determine product quality and equipment safety. The high-purity heat-resistant quartz crucible is made of ultra-high purity silicon dioxide raw material, combined with advanced arc melting or vacuum defoaming processes, and has extremely low impurity content (total impurities<20ppm), excellent thermal shock stability, and long-term temperature resistance (continuous use temperature of 1100 ℃ -1250 ℃, short-term can reach 1400 ℃). It effectively avoids the migration and contamination of materials by metal ions at high temperatures, and is an ideal load-bearing container for high demand scenarios such as crystal growth, powder sintering, and metal melting.

Frequently Asked Questions (FAQ)

Q1: How high temperature can a quartz crucible withstand? Will it rupture under rapid heating and cooling?  

A: Our high-purity quartz crucible has a softening point of about 1650 ℃, and it is recommended to work at a temperature of ≤ 1250 ℃ for a long time. Quartz material has an extremely low coefficient of thermal expansion (about 5.5 × 10 ⁻⁷/℃), excellent thermal shock resistance, and can be directly air-cooled from 1000 ℃ to room temperature without cracking. It is suitable for frequent temperature rise and fall processes.

Q2: Ordinary ceramic crucibles can contaminate samples. How high is the purity of your crucibles?  

A: Ordinary ceramics contain impurities such as Al, Na, Fe, etc., which are prone to diffusion at high temperatures. Our product has a SiO ₂ purity of ≥ 99% and a total metal impurity content of<20ppm (typical value 15ppm), especially alkali metals (K, Na)<2ppm, meeting the stringent requirements for trace pollution in semiconductor and high-purity material melting.

Q3: Can non-standard shapes, special wall thicknesses, or covered crucibles be customized?  

A: Okay. We support customization of outer diameter ranging from 10mm to 600mm and height ranging from 10mm to 800mm, with wall thickness controlled between 2-15mm. We also offer square, conical, overflow groove, observation window or sealed crucible with lid, with flexible minimum order quantity.

Q4: Will there be slag or bubbles falling off the surface of the crucible?  

A: We use vacuum arc melting and inner wall bubble free layer technology, with a dense and smooth inner surface, no visible bubbles or pores, to prevent slag from contaminating the material. At the same time, it can provide options for semi transparent or completely transparent layers on the inner wall, making it easy to observe the state of the melt.

What core needs can the product solve for you?

-Avoid high temperature pollution: solve the problems of product scrap, lattice defects, or decreased electrical performance caused by impurity infiltration.  

-Resistance to thermal shock cracking: solves the problems of crucible explosion, furnace damage, and production interruption during rapid cooling and heating.  

-Adapt to complex processes: solve the problem of standard sizes not matching special equipment or materials with special shapes.  

-Extend service life: Solve the cost and time waste caused by frequent replacement of crucibles.

Typical application scenarios

Semiconductor: silicon crystal growth, gallium arsenide synthesis, oxide crystal pulling, extremely low alkali metal, preventing carrier concentration shift

Photovoltaic: Quartz crucibles for polycrystalline silicon ingots and monocrystalline silicon pulling, large size (28-36 inches), high inner wall purity

Laboratory: High temperature ashing, XRF melt preparation, special glass melting, no cross contamination, chemically inert

Optical coating: The evaporated coating material is melted (such as MgF ₂, SiO ₂), without splashing or bubble rupture splashing

Powder metallurgy: melting of high-temperature alloys and rare earth alloys, corrosion-resistant and non stick to metals

Actual problems solved:

Problem 1: During the single crystal drawing process of photovoltaic customers, crucible crystallization leads to edge breakage

-Phenomenon: Using a regular crucible, the crystallization layer on the inner wall thickens during the later stage of crystal pulling, and the silicon solution penetrates and corrodes the crucible, resulting in uneven resistivity and even crystal breakage of the crystal rod.  

-Our solution: Provide high-purity synthetic quartz crucibles (natural quartz+synthetic quartz composite layer) with a crystallization rate reduced by over 60%.  

-Result: The yield of single crystal products increased by 12%, and the single use time of the crucible was extended from 200 hours to 280 hours.

Problem 2: A special glass research institute melted boron containing glass, but cracks appeared in the ordinary crucible and contaminated the glass liquid

-Our plan: custom shaped crucible with uniform wall thickness and arc bottom, made of high-purity fused silica, and pre fired to eliminate stress.  

-Result: The clarity of the glass liquid has been improved without any microcracks, and it can be reused more than 5 times.

Question 3: North American semiconductor equipment manufacturers require ultra clean square crucibles with chamfered edges for wafer diffusion processes

-Our solution: We provide customized square crucibles with flame polished edges and sandblasted inner surfaces after precision machining, and use double-layer PE bags and dust-free vacuum packaging.  

-Result: Passed the customer's Class 10 cleanliness test.

Customer Case (Anonymous)

Case A (Photovoltaic Monocrystalline Silicon)

-Requirement: A 32 inch large-sized quartz crucible with no bubble layer on the inner wall and a service life of over 250 hours.  

-Solution: Adopting a composite structure of high-purity synthetic inner layer and natural quartz outer layer, vacuum filtration molding, and high-temperature dehydroxylation treatment.  

-Effect: The actual crystal pulling time has reached 268 hours, and the lifespan of the crystal rod head has been increased by 15%. Six consecutive batches have been purchased.

Case B (Advanced Materials Laboratory in Universities)

-Requirement: Various small capacity (5ml-50ml) irregular crucibles for molten salt corrosion experiments, requiring resistance to rapid cooling.  

-Solution: Provide high-purity quartz material with a lid design, a wall thickness of 3mm, and can withstand repeated solidification quenching of molten salt (NaCl KCl) at 900 ℃.  

-Effect: Using 50 cycles without leakage or rupture significantly improves the reproducibility of experimental data.

Case C (Optical Coating Company)

-Requirement: When plating high refractive index film layers, splashing of the inner film material in ordinary crucibles can cause pinholes in the film layer.  

-Solution: Customized quartz crucible with mirror polished inner walls, no bubbles, and a splash proof ring with a closed mouth.  

-Effect: The pinhole density of the film layer decreased from 20 per square centimeter to 0-2, and the coating yield increased from 82% to 96%.

Whether you need standard circular crucibles, square, conical, porous crucibles, or crucibles with handles, we can produce according to the drawings and samples. Welcome to provide size, purity requirements, and operating temperature. We will provide technical solutions and quotations. Contact us immediately for sample or small batch trial support.

Luverre Quartz manufactures and sells a wide range of high quality quartz glass, including quartz tubes, quartz plates, quartz rods, quartz windows, quartz crucibles, quartz boats, quartz flanges, quartz beakers, quartz glass instruments, and more. We can meet all kinds of customized requirements for quartz glass products.