Operando Analysis of Electron Devices Using Nanodiamond Thin Films Containing Nitrogen-Vacancy Centers

Abstract

Operando analysis of electron devices provides key information regarding their performance enhancement, reliability, thermal management, etc. For versatile operando analysis of devices, the nitrogen-vacancy (NV) centers in diamonds are potentially useful media owing to their excellent sensitivity to multiple physical parameters. However, in single crystal diamond substrates often used for sensing applications, placing NV centers in contiguity with the active channel is difficult. This study proposes an operando analysis method using a nanodiamond thin film that can be directly formed onto various electron devices by a simple solution-based process. The results of noise analysis of luminescence of the NV centers in nanodiamonds show that the signal-to-noise ratio in optically detected magnetic resonance can be drastically improved by excluding the large 1/ f noise of nanodiamonds. Consequently, the magnetic field and increase in temperature caused by the device current could be simultaneously measured in a lithographically fabricated metal microwire as a test device. Moreover, the spatial mapping measurement is demonstrated and shows a similar profile with the numerical calculation.

Widefield quantum microscopy with nitrogen-vacancy centers in diamond: strengths, limitations, and prospects

“…82,83 Measuring temperature alongside magnetic fields in a widefield NV microscope is also of potential interest for electronics applications, enabling the in situ monitoring of Joule heating while imaging the current density in an operating device. 19,20,68,69 However, a single-crystal diamond in contact with the device of interest thermalizes rapidly and acts as a heat sink, and so these applications are often tackled using a modified version of a widefield NV microscope whereby a layer of nanodiamonds that are thermally decoupled from each other is formed onto the electronic device. 19,20,68 The temperature response of the D parameter also becomes vanishingly small at cryogenic temperatures (below 100 K), 77 which prevents in situ temperature monitoring in cryogenic widefield NV microscopy experiments.…”

“…19,20,68,69 However, a single-crystal diamond in contact with the device of interest thermalizes rapidly and acts as a heat sink, and so these applications are often tackled using a modified version of a widefield NV microscope whereby a layer of nanodiamonds that are thermally decoupled from each other is formed onto the electronic device. 19,20,68 The temperature response of the D parameter also becomes vanishingly small at cryogenic temperatures (below 100 K), 77 which prevents in situ temperature monitoring in cryogenic widefield NV microscopy experiments. 36 In contrast, magnetic field sensing with NV centers performs similarly at room and cryogenic temperatures, and does not suffer from screening effects because most materials including the diamond are magnetically transparent.…”

“…1(a). We will also discuss implementations that use nanodiamond films instead of a bulk diamond, 19,20 as well as those that employ raster scanning rather than parallel imaging with a camera. 21 Common to these NV microscopy variants is their optically limited spatial resolution, a key consideration when comparing with other microscopy techniques.…”

“…64 Applications in electronics also include probing currents in the microwave regime [65][66][67] and temperature mapping of electronic circuits. 19,20,68,69 The purpose of this Perspective is to analyze some of these applications in more detail and, considering the current state of the art of widefield NV microscopy, identify the strengths and shortcomings compared to other microscopy techniques typically used. The key features of widefield NV microscopy that are often put forward are its high magnetic sensitivity, its versatility and simplicity, its high spatial resolution, and its ability to accurately measure a sample's magnetic properties.…”

Effect of metal electrodes on optically detected magnetic resonance of nitrogen vacancy centers in diamond

“…10) As the entire ODMR spectrum provides multiple physical parameters, such as magnetic field, 11,12) electric field, 13) pressure, 14) and temperature 15,16) with ultrahigh sensitivity by the variation of the resonance frequency, 17) simultaneous multiparametric operando analysis of electronic devices can be possible with NV centers. 18) The sensitivity in measuring these physical parameters depends on the ODMR contrast and the coherence time and density of NV centers. 12) One of the concerns of the ODMR-based operando analysis of electronic devices is the effect of the existence of metal electrodes on the ODMR signal.…”