K-band single-chip electron spin resonance detector.

Area of Science:

• Microsystems engineering
• Spectroscopy
• Solid-state physics

Background:

• Electron spin resonance (ESR) spectroscopy is a powerful technique for studying materials with unpaired electrons.
• Miniaturization of ESR detectors is crucial for portable and high-throughput applications.
• Current ESR systems often require bulky and expensive equipment.

Purpose of the Study:

• To design and fabricate a compact, integrated detector for electron spin resonance (ESR) spectroscopy.
• To achieve high spin sensitivity using complementary metal-oxide-semiconductor (CMOS) technology.
• To demonstrate the performance of the integrated detector at room temperature and cryogenic conditions.

Main Methods:

• Fabrication of a silicon chip microsystem using conventional CMOS technology.
• Integration of an LC-oscillator and a frequency division module on a single chip.
• Characterization of the detector's performance, including spin sensitivity and sensitive volume.

Main Results:

• Successful design, fabrication, and characterization of an integrated ESR detector operating at 27 GHz.
• Achieved a room temperature spin sensitivity of approximately 10^8 spins/sqrt(Hz).
• Demonstrated operation at both room temperature and 77K, with a sensitive volume of (100 μm)^3.

Conclusions:

• The integrated ESR detector represents a significant advancement in miniaturizing spectroscopic instrumentation.
• The developed CMOS-based microsystem offers high performance and potential for widespread adoption.
• This technology paves the way for more accessible and versatile ESR spectroscopy applications.