Formation of p-n⁺ diamond homojunctions by shallow doping of phosphorus through liquid emersion excimer laser irradiation

Abstract

We report the fabrication of p-n⁺ diamond homojunction through an innovative approach of laser irradiation in liquid-ambient. A shallow phosphorus-doped layer with a high electric conductivity is processed on top of a p-type diamond substrate to form the p-n⁺ homojunction. The current–voltage measurements at room temperature confirmed high conductivity of the induced n⁺ layer and showed exceptional rectification properties with an ideality factor of 1.07, excellent low on-resistance of 3.7 × 10⁻² Ωcm², and current density over 260 Acm⁻² at forward-biasing of 10 V. Furthermore, undetectable leakage-current provides a rectification ratio exceeding 10¹⁰ at ±6 V, promoting the junction in UV detection applications.

GRAPHICAL ABSTRACT

IMPACT STATEMENT

The process allows further selective and feasible patterned/shallow doping of diamond surfaces beyond the conventional methods, with minimal power consumption and fast production rate, providing more readily electrically contacted devices.

KEYWORDS:

• Shallow doping
• laser processing
• diamond devices
• p–n junctions
• detectors

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Supporting Information is provided for a detailed discussion regarding modeling of ablation temperature, and substrate optical and Raman characterization.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was supported by the Japan Society for the Promotion of Science (JSPS KAKENHI Grant Nos. JP19H02436 and 21K18830), and partially funded by JAEA Nuclear Energy S&T and Human Resource Development Project through concentrating wisdom [grant no. JPJA19B19210378].