<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mrow><mml:mrow><mml:mi mathvariant="normal">N</mml:mi></mml:mrow></mml:mrow></mml:math>
-
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mi>V</mml:mi></mml:math>
–Diamond Magnetic Microscopy Using a Double Quantum 4-Ramsey Protocol

Hart, Connor; Schloss, Jennifer; Turner, Matthew; Scheidegger, Patrick; Bauch, Erik; Walsworth, Ronald L.

doi:10.1103/physrevapplied.15.044020

Cited by 43 publications

(17 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sensitivity of NV-diamond magnetic sensors is improving every year as the technology matures [17,37]. Continued technology improvements will also further advance the capabilities of magnetic field mapping with wide-field QDM measurements.…”

Section: Discussionmentioning

confidence: 99%

Vector Magnetic Current Imaging of an 8 nm Process Node Chip and 3D Current Distributions Using the Quantum Diamond Microscope

Oliver

Martynowych

Turne

et al. 2021

International Symposium for Testing and Failure Analysis

Self Cite

View full text Add to dashboard Cite

The increasing trend for industry adoption of three-dimensional (3D) microelectronics packaging necessitates the development of new and innovative approaches to failure analysis. To that end, our team is developing a tool called the quantum diamond microscope (QDM) that leverages an ensemble of nitrogenvacancy (NV) centers in diamond for simultaneous wide fieldof- view, high spatial resolution, vector magnetic field imaging of microelectronics under ambient conditions [1,2]. Here, we present QDM measurements of two-dimensional (2D) current distributions in an 8 nm process node flip chip integrated circuit (IC) and 3D current distributions in a custom, multi-layer printed circuit board (PCB). Magnetic field emanations from the C4 bumps in the flip chip dominate the QDM measurements, but these prove to be useful for image registration and can be subtracted to resolve adjacent current traces on the micron scale in the die. Vias, an important component in 3D ICs, display only Bx and By magnetic fields due to their vertical orientation, which are challenging to detect with magnetometers that traditionally only measure the Bz component of the magnetic field (orthogonal to the IC surface). Using the multi-layer PCB, we demonstrate that the QDM's ability to simultaneously measure Bx, By, and Bz magnetic field components in 3D structures is advantageous for resolving magnetic fields from vias as current passes between layers. The height difference between two conducting layers is determined by the magnetic field images and agrees with the PCB design specifications. In our initial steps to provide further z depth information for current sources in complex 3D circuits using the QDM, we demonstrate that, due to the linear properties of Maxwell's equations, magnetic field images of individual layers can be subtracted from the magnetic field image of the total structure. This allows for isolation of signal from individual layers in the device that can be used to map embedded current paths via solution of the 2D magnetic inverse. Such an approach suggests an iterative analysis protocol that utilizes neural networks trained with images containing various classes of current sources, standoff distances, and noise integrated with prior information of ICs to subtract current sources layer by layer and provide z depth information. This initial study demonstrates the usefulness of the QDM for failure analysis and points to technical advances of this technique to come.

show abstract

Section: Discussionmentioning

confidence: 99%

Vector Magnetic Current Imaging of an 8 nm Process Node Chip and 3D Current Distributions Using the Quantum Diamond Microscope

Oliver

Martynowych

Turne

et al. 2021

International Symposium for Testing and Failure Analysis

Self Cite

View full text Add to dashboard Cite

show abstract

“…1c (see also Appendix D). This QDM uses a Heliotis HeliCam lock-in camera, described in detail in [58], to quickly acquire NV fluorescence images. Fig.…”

Section: Experimental Demonstrations Of Interferometric Strain Micros...mentioning

confidence: 99%

“…For the widefield imaging reported in this work, we used a quantum diamond microscope (QDM) apparatus and Heliotis heliCam C3 camera -both described in detail in Ref. [58]. The heliCam C3 subtracts alternating NV fluorescence exposures in hardware, and digitizes only their difference, allowing the measurement contrast to fill each pixel's 10-bit dynamic range.…”

Section: Appendix C: Confocal Microscopementioning

confidence: 99%

“…In Ref. [58], this offset was subtracted with a separate calibration measurement for each field-of=view on the diamond, in preparation to sense magnetic fields due to an additional sample signal. The strain-sensing applications addressed here typically require quickly imaging many diamond fields-ofview, and preclude a full calibration measurement at each one.…”

Section: Appendix C: Confocal Microscopementioning

confidence: 99%

See 1 more Smart Citation

High-precision mapping of diamond crystal strain using quantum interferometry

Marshall¹,

Ebadi²,

Hart³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Crystal strain variation imposes significant limitations on many quantum sensing and information applications for solid-state defect qubits in diamond. Thus, precision measurement and control of diamond crystal strain is a key challenge. Here, we report diamond strain measurements with a unique set of capabilities, including micron-scale spatial resolution, millimeter-scale field-of-view, and a two order-of-magnitude improvement in volume-normalized sensitivity over previous work [1], reaching 5(2) × 10 −8 / Hz • µm 3 (with spin-strain coupling coefficients representing the dominant systematic uncertainty). We use strain-sensitive spin-state interferometry on ensembles of nitrogen vacancy (NV) color centers in single-crystal CVD bulk diamond with low strain gradients. This quantum interferometry technique provides insensitivity to magnetic-field inhomogeneity from the electronic and nuclear spin bath, thereby enabling long NV ensemble electronic spin dephasing times and enhanced strain sensitivity. We demonstrate the strain-sensitive measurement protocol first on a scanning confocal laser microscope, providing quantitative measurement of sensitivity as well as three-dimensional strain mapping; and second on a wide-field imaging quantum diamond microscope (QDM). Our strain microscopy technique enables fast, sensitive characterization for diamond material engineering and nanofabrication; as well as diamond-based sensing of strains applied externally, as in diamond anvil cells or embedded diamond stress sensors, or internally, as by crystal damage due to particle-induced nuclear recoils.

show abstract

“…Solid-state spin systems have transitioned from physics demonstrations to promising quantum sensors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] as performance has improved through materials engineering [17][18][19][20][21][22][23][24][25], coherent control [26][27][28][29][30][31][32][33][34][35], and novel readout [36][37][38][39][40][41][42][43]. While performance now rivals atomic-based sensors [44][45][46][47][48][49], solid-state systems still maintain much of the complexity of their atomic counterparts …”

Section: Introductionmentioning

confidence: 99%