Direct from our Donghai precision manufacturing facility: precision ground, flame-polished, and leak-tested quartzware deployed across laboratory and industrial thermal lines.
Why modern advanced biophotonics, semiconductor wafer metrology, and high-energy physics are migrating entirely from standard borosilicate glass to custom synthetic fused silica and quartz cover slips.
Standard borosilicate or soda-lime microscope coverslips contain metallic impurities (iron, boron, aluminum, titanium) that emit intense parasitic autofluorescence when irradiated with UV, violet, or short-wave laser lines (such as 266 nm, 355 nm, 405 nm, and 488 nm). In single-molecule fluorescence resonance energy transfer (smFRET) and Total Internal Reflection Fluorescence (TIRF) microscopy, background photon emissions completely bury single fluorophore photons.
As an authoritative custom quartz cover slips manufacturer, we fabricate ultraclean synthetic fused silica (JGS1 grade) substrates containing less than 0.1 ppm heavy metal contaminants. This yields a virtually non-existent fluorescent background, ensuring signal-to-noise ratios (SNR) above 15:1 for localized single-molecule detection.
Super-resolution nanoscopy platforms—including STORM, PALM, and STED—require extreme wavefront precision. Commercial cover slips with thickness variations or surface waviness cause severe spherical aberration, distorting the Point Spread Function (PSF) and limiting axial resolution.
Advanced biochemical chips and flow cells undergo aggressive cleaning cycles, including hot piranha solutions (H₂SO₄ + H₂O₂), concentrated aqua regia, and prolonged exposure to reactive silanes during self-assembled monolayer (SAM) passivation. Common optical glasses pit, etch, and leach metal ions within minutes.
Our custom quartz cover slips maintain molecular integrity across prolonged exposures to concentrated acids, organic solvents, and high-power ozone/plasma cleaning, guaranteeing clean covalent bonding surfaces for DNA tethering and lipid bilayer assembly.
Engineered to German microscope DIN / ISO 8255 standards and custom OEM geometry requirements for advanced analytical flow chambers.
| Class Designation | Nominal Thickness (μm) | Standard Tolerance | Primary Material Grade | Typical Industrial & Research Applications |
|---|---|---|---|---|
| No. 00 (Ultra-Thin) | 55 – 80 μm | ±5 μm | Synthetic Fused Silica (JGS1) | Dual-objective 4Pi microscopy, high NA immersion lens proximity |
| No. 0 | 80 – 130 μm | ±8 μm | Optical Fused Quartz (JGS2) | High-throughput DNA sequencing chips, microfluidic covers |
| No. 1 | 130 – 160 μm | ±5 μm | Synthetic Fused Silica (JGS1) | UV-Vis confocal scanning, live-cell fluorescence assays |
| No. 1.5 (Standard Flagship) | 160 – 190 μm (Nom. 170 μm) | ±3 μm (Ultra-Precise) | Synthetic Silica / Fused Quartz | Standard immersion microscope objectives (NA > 1.4), TIRF, STED |
| No. 2 | 190 – 250 μm | ±10 μm | High Purity Fused Quartz | Pressure-resistant microfluidic chambers, optical viewports |
| Quartz Slides (Standard) | 1.0 mm / 0.5 mm / 0.2 mm | ±0.02 mm | JGS1 / JGS2 / JGS3 | Spectrophotometer baselines, laser damage testing, cryostats |
Our custom quartz coverslips utilize high-purity synthetic fused silica (JGS1), maintaining >91% internal transmission starting from 190 nm through the visible spectrum and into near-infrared at 2200 nm. In contrast, standard laboratory coverslips suffer catastrophic absorption cutoffs at 340 nm. This broad transmission makes quartz indispensable for deep-UV Raman spectroscopy, two-photon microscopy, and multi-wavelength laser tweezer trapping.
With an extremely low coefficient of thermal expansion (α ≈ 5.5 × 10⁻⁷ / K), custom quartz cover slips withstand thermal differentials >1000 °C without micro-fracturing. Samples can be flash-frozen directly into liquid nitrogen (−196 °C) for cryo-fluorescence or laser-heated above 800 °C for in-situ high-temperature material phase transformation studies without optical distortion or cracking.
From cleanroom automated semiconductor scanners to quantum photonics and next-generation gene sequencing flow cells, custom quartz slips deliver uncompromising precision.
Modern high-capacity genomic sequencers operate continuous four-color laser scanning over extensive microfluidic channel arrays. Our custom-diced rectangular and circular quartz cover slips (e.g., 24×60 mm, 25×75 mm, or custom 150 mm round wafers) act as the structural observation ceiling. They resist chemical degradation from enzyme flushing, maintain precise focal depth under continuous fluid pressure, and allow pristine excitation photon transfer.
In deep sub-micron semiconductor defect inspection systems, deep UV light (193 nm and 248 nm) inspects wafer patterns. Quartz slips function as protective optical shields, debris barriers, and transparent reference standards. Their ultra-flat parallelism prevents optical astigmatism, while zero bubble inclusions (ISO 10110 Class 0) eliminate false positive defect triggering.
Quantum computing laboratories investigating nitrogen-vacancy (NV) center electron spins in synthetic diamonds require cover slips that perform reliably inside ultra-high vacuum (UHV) cryostats at 4 Kelvin. Fused quartz eliminates trapped gas bubbling, prevents dielectric charge buildup, and maintains laser polarization fidelity across magnetic resonance microwave excitations.
Understanding the multi-stage cold machining, chemical mechanical planarization (CMP), and laser dicing that define world-class quartz manufacturing.
High-purity plasma-melted synthetic quartz ingots undergo crystal orientation verification before multi-diamond-wire sawing. By maintaining sub-micron tension control and temperature-stabilized slurries, kerf loss is minimized and micro-crack propagation into the bulk quartz matrix is prevented.
Thin quartz plates proceed through multi-stage planetary double-sided lapping with progressively finer aluminum oxide and cerium oxide slurries. Chemical Mechanical Planarization (CMP) removes sub-surface damage, achieving super-polished finishes with Ra < 0.5 nm and parallelism < 2 arcseconds.
Traditional mechanical wheel scribing causes catastrophic edge chipping on 0.17 mm thin quartz. Southeast Quartz uses non-thermal picosecond and femtosecond laser dicing. This ensures edge chip dimensions <10 μm, prevents stress fractures, and allows custom internal micro-holes, notches, and fluidic inlet ports.
Finished slips are chemically sanitized through heated cascading deionized water, multi-frequency megasonic baths, and non-ionic surfactant stripping inside a Class 100 (ISO Class 5) cleanroom. Each cover slip is packaged with cleanroom-certified, lint-free, vacuum-sealed barrier packaging ready for immediate sterile bio-coupling.
Expanding from ultra-thin cover slips to structural plates, high-temperature furnace tubes, and heavy-duty reactor vessels.
Clear, definitive guidance on specifying tolerances, selecting material purity grades, and avoiding optical artifacts.
The differences lie in elemental purity and optical performance. Borosilicate glass contains up to 13% boron oxide and residual metallic oxides that trigger strong autofluorescence across ultraviolet and visible wavebands, severely obscuring fluorophore emissions. Furthermore, borosilicate cuts off transmission sharply below 340 nm. Fused quartz (especially synthetic JGS1 grade) offers >99.999% pure SiO₂, transmitting light down to 190 nm with practically zero autofluorescence, while supporting operating temperatures beyond 1,100 °C.
High numerical aperture (NA > 1.2 to 1.49) oil and silicone immersion objectives are calibrated precisely for a 0.170 mm cover glass thickness with refractive index nd ≈ 1.458. Even a slight deviation of ±10 μm introduces primary spherical aberration, which spreads focal energy, degrades axial resolution, and blurs single-molecule localization microscopy (SMLM). We lap and polish our standard No. 1.5H coverslips to a tightened tolerance of 170 ± 3 μm to protect diffraction-limited imaging performance.
We support fully customized geometries according to customer CAD (DWG, DXF, STEP) drawings. Beyond standard rectangular (22×22 mm, 24×50 mm, 24×60 mm) and circular (9 mm, 12 mm, 25 mm diameter) dimensions, we fabricate multi-well patterns, laser-machined micro-through-holes (down to 100 μm diameter), fluidic chamfers, step-notches, and polished bevel edges on slips ranging from 60 μm to 2.0 mm thick.
Every production run undergoes strict quality control at our Donghai facility: optical profilometry for surface microroughness (Ra), spectrophotometric verification of DUV-NIR transmission, interferometric laser wavefront testing for flatness, helium mass spectrometer leak detection (for vacuum or pressure-sealed assemblies), and cleanroom optical particle counting.
Following polishing and dicing, parts are stripped of organic and particulate residues via sulfuric acid-peroxide piranha immersion, ultrasonic deionized rinsing, and non-contact hot nitrogen drying in an ISO Class 5 cleanroom. Slips are packed in vacuum-sealed fluoropolymer / ESD-safe multi-cavity trays to prevent friction scratch damage or electrostatic dust accumulation during international air transit.
