Launch of Low-Nitrogen Content Substrates

Our company's primary advantage is our ability to produce large, high-purity single-crystal diamonds. We have been selling substrates, wafers, and epi-wafers for diamond device development, seed crystals for laboratory-grown diamond (LGD, artificial gemstones) manufacturing, and optical components. To produce diamond materials suitable for various applications, we have continuously focused on developing large crystals since our founding. We are pleased to announce that we will now be launching substrates and wafers of various sizes with reduced nitrogen content.

1. Introduction

Diamond possesses excellent semiconductor properties and is expected to be applicable in high-power control power devices and high-frequency, high-output devices. The manufacturing of such applications is envisioned to be done on large wafers. Since our establishment, we have been working on scaling up single-crystal diamonds, and we commercialized a 1-inch wafer in April 2025. However, until now, the nitrogen content of the single-crystal diamonds we have commercialized has been up to 8 ppm, with some exceptions. In the development of semiconductor devices, high nitrogen content can hinder a wide range of applications, and many users have requested diamond substrates with low nitrogen content.

We have already launched (111) substrates with a nitrogen content of 0.5 ppm or less. However, we had not previously sold low-nitrogen substrates for (100) substrates, which are most frequently used in device development. This is due to manufacturing reasons: the presence of a small amount of nitrogen in the reaction gas during diamond growth stabilizes the growth, suppresses the formation of defects such as polycrystals, and improves the growth rate. Therefore, we have supplied materials with a certain amount of nitrogen as products to ensure stable characteristics.

On the other hand, as diamond device development has diversified, it has become an important challenge for us to provide diamond substrates and wafers with materials that meet these development needs. We have now commercialized low-nitrogen substrates and wafers to meet these market demands.

2. Details of Newly Launched Products

Substrates and wafers for diamond device development [Photo 1]

Size: 1x1mm to 30x30mm, 1-inch wafer

Thickness: 0.03 to 4mm

Crystal plane: (100), (110), (111)

If not specified, a 3° off-angle is provided.

(111) and (110) plane substrates have size limitations.

Nitrogen content: 0.5 ppm or less

3. Applications

These can be used as substrates for power devices and high-frequency devices, as before. Due to the low nitrogen content, the pseudo-n-type characteristics will be reduced, but the withstand voltage characteristics will be equivalent to conventional products. Furthermore, in quantum device-related development, the N-V center content will be lower compared to conventional products.

When used as optical components, the transmittance at wavelengths below 500nm has improved, and the transmittance of blue and ultraviolet light has been enhanced.

As for other characteristics, the thermal conductivity is 2000W/m·K, and they can be handled in the same way as previous substrates.

Photo 1: Photographs of 10x10mm and 15x15mm substrates

Contact Information for Inquiries

EDP Inc. Sales Department

4-6-3 Kamishinden, Toyonaka-shi, Osaka 560-0085

(Email) edp.info@d-edp.jp

HP: https://www.d-edp.jp/