  Temperature sensors with micro- and nanoscale spatial resolution have long
been explored for their potential to investigate the details of physical
systems at an unprecedented scale. In particular, the rapid miniaturization of
transistor technology, with the associated steep boost in power density, calls
for sensors that accurately monitor heating distributions. Here, we report on a
simple and scalable fabrication approach, based on directed self-assembly and
transfer printing techniques, to construct arrays of nanodiamonds containing
temperature sensitive fluorescent spin defects. The nanoparticles are embedded
within a low thermal conductivity matrix that allows for repeated use on a wide
range of systems with minimal spurious effects. Additionally, we demonstrate
access to a wide spectrum of array parameters ranging from sparser single
particle arrays to denser devices with approximately 100 % yield and stronger
photoluminescence signal, ideal for temperature measurements. With these we
experimentally reconstruct the temperature map of an operating coplanar
waveguide to confirm the accuracy of these platforms.
