Providing the material backbone for High-Power AI Infrastructure, Strategic Defense, and Quantum Metrology — grown exclusively by Microwave Plasma CVD (MPCVD), certified under the Vajra-Sāra™ protocol, and delivered with a lot-level Certificate of Analysis.
Our proprietary vetting and characterization engine. Every MPCVD substrate is evaluated against grade thresholds before receiving a Vajra-Crest designation — Raman spectroscopy, AFM surface mapping, SIMS purity analysis, and laser-flash thermal diffusivity testing.
Only MPCVD substrates that pass the full Vajra-Sāra protocol are released under the Vajra-Crest designation — the technical guarantee extended to quantum information science, power electronics, and global scientific instrumentation. Integrated picosecond laser machining enables custom geometries with ±10 µm accuracy.
All grades sourced exclusively via MPCVD.
Each lot is grade-assigned under Vajra-Sāra™ protocol.
| Parameter | Specification | Test Method | Grade |
|---|---|---|---|
| Thermal Conductivity | 1800–2000 W/m·K | Laser-flash diffusivity, ASTM E1461 | HTG |
| Surface Roughness Ra (Single Crystal) | < 1 nm | AFM, 10×10 µm scan area | HTG |
| Surface Roughness Ra (Polycrystalline) | < 5 nm | AFM, 10×10 µm scan area | STD |
| Crystal Structure | Single Crystal / PCD (MPCVD) | Raman FWHM < 2 cm⁻¹ | HTG |
| Isotopic Purity (¹²C) | > 99.99% | SIMS depth profiling | HTG |
| Nitrogen Content (Standard) | < 1 ppm | SIMS / EPR spectroscopy | STD |
| Nitrogen Content (Special Request) | < 0.05 ppm | SIMS depth profiling | HTG |
| CTE (20–300 °C) | ~1.0 × 10⁻⁶ K⁻¹ | DIL 402 pushrod dilatometer | STD |
| Substrate Diameter | Up to Ø 100 mm | Optical metrology | STD |
| Custom Geometry (Laser) | 1 mm – 10 mm, ±10 µm | Picosecond laser machining | STD |
| Thickness Tolerance | ± 5 µm | Single-point diamond turning | HTG |
| Dielectric Constant (εᵣ) | 5.7 @ 1 MHz | Impedance spectroscopy | STD |
| Breakdown Voltage | > 10 MV/cm | High-voltage probe station | STD |
| Optical Transparency | UV–IR (225 nm – 25 µm) | FTIR & UV-Vis spectroscopy | STD |
* All specifications subject to lot-level Certificate of Analysis (CoA). HTG = 1800–2000 W/m·K Ultra-Thermal Grade. Custom tolerances and isotopic enrichment available for qualified research and defense contracts.
Key intrinsic properties of MPCVD diamond substrate — matched to Si, GaN, and SiC device stacks.
During our MPCVD growth and Vajra-Sāra™ characterization process, substrates that do not achieve optical surface grade or full geometry tolerances are classified as Industrial High-Thermal Rejects. These substrates maintain ≥1400 W/m·K thermal conductivity and are fully viable for non-optical heat-spreading applications — offered at significantly reduced cost with full thermal CoA.
Industrial Rejects are available in limited quantities on a per-lot basis. Enquire via solutions@vajra-crest.com with your thermal floor requirement and geometry. Minimum order applies.
Type IIa Single-Crystal MPCVD · Purity-First Protocol
| Parameter | Symbol | Specification | Verification Method |
|---|---|---|---|
| Grade Classification | — | Quantum / Electronic Grade (Type IIa) | MPCVD Single Crystal |
| Nitrogen Content | [N] | < 5 ppb | SIMS / EPR Spectroscopy |
| Boron Content | [B] | < 1 ppb | SIMS Depth Profiling |
| Surface Roughness | Ra | < 5 nm (Super-polished) | AFM 10×10 µm |
| Crystal Orientation | — | {100} Standard · {111} on request | XRD / EBSD |
| Dislocation Density | ρd | < 105 cm−2 | Etch Pit / Birefringence Map |
Custom doping (Nitrogen/Boron) and isotopic enrichment (12C) available for specific NV-center research requirements.
Vajra-Crest provides the high-coherence "vacuum" required for next-generation quantum sensing. Our substrates are engineered to minimize paramagnetic noise, enabling unprecedented sensitivity in Magnetic Current Imaging (MCI) — where every part-per-billion of nitrogen or boron translates directly to decoherence and lost signal fidelity.
NV-center performance is governed not by the diamond itself, but by the
impurity landscape surrounding each spin. Substitutional nitrogen ([Ns0])
is the dominant paramagnetic bath; boron introduces competing spin-½ defects.
Vajra-Crest Type IIa substrates are grown under MPCVD conditions optimised
for radical impurity suppression — delivering the clean host matrix that
coherence time T2 demands.
Plasma-etched {100} surfaces eliminate sub-surface damage layers
that would otherwise scatter implanted nitrogen ions, producing a
strain-free landing zone for delta-doped NV layers.
Every substrate ships ESR-characterised and PL-mapped,
so your implantation team starts with confirmed coherence baseline data,
not assumptions.
Vajra-Crest operates precision picosecond laser machining for custom substrate geometries. The ultrashort pulse duration (<10 ps) minimises heat-affected zones, preserving the thermal and crystalline integrity of the diamond substrate at cut edges — critical for precision semiconductor and defence packaging applications.
Diamond is the only substrate that addresses the thermal wall in dense AI accelerator stacks and GaN-on-Diamond power devices. Ultra-Thermal Grade substrates deliver guaranteed 1800–2000 W/m·K — measured per lot under LFA ASTM E1461, not nominal values. Integrated picosecond laser machining produces custom heatspreader geometries at ±10 µm.
Defense-grade and institutional-grade procurement demands substrate consistency across lots, not just across samples. Every Vajra-Crest delivery carries a lot-level Certificate of Analysis under the Vajra-Sāra™ protocol — covering thermal conductivity, surface finish, purity, and crystallographic quality. Standard NDA executed at inquiry; defence-specific annexes available.
NV-center coherence time T2 is directly limited by the paramagnetic impurity landscape of the host diamond. Vajra-Crest Type IIa substrates push nitrogen below 5 ppb and boron below 1 ppb — verified by SIMS and EPR. Isotopically purified 12C (>99.999%) eliminates the 13C nuclear spin bath. Substrates ship PL-mapped and ESR-characterised.
Every substrate undergoes our proprietary spectroscopic and thermal characterization protocol before release under the Vajra-Crest designation.
Processes designed to meet international quality management standards for advanced materials, supporting procurement audit requirements.
100% lead-free and chemical-safe synthetic diamond substrates. No hazardous substances — fully compliant with EU and international environmental directives.
All materials are lab-grown via MPCVD with a transparent, traceable, and sustainable supply chain. Zero reliance on artisanal or mined diamond.
Compliant with international shipping and trade regulations for dual-use advanced materials. Documentation packages available for customs and institutional procurement.
We partner with global research facilities, quantum technology labs, and deep-tech innovators. Submissions are reviewed by our materials science team within 72 hours. All technical requirements are treated with strict confidentiality under our standard NDA framework.