In modern electronics, thermal management becomes one of the most crucial factors in the determination of the performance, quality and lifetime of devices. Especially with the development of internet of things and the digitization of worldwide information, the need for storage of giant amount of data and processing with fast speed is escalating. As a consequence, the density of devices on integrated circuit (IC) chips is becoming increasingly compact, which further reduces the size of devices even to the nanoscale and uniform power distributions and efficient thermal routing becomes more and more tricky. Moreover, novel materials and devices are emerging which may have unconventional properties such as being anisotropic or flexible so that traditional thermal management techniques may not be applicable. Therefore, it is crucial to develop more advanced thermal management strategy for modern and novel devices and to improve the efficiency of energy harvest, for example, using thermoelectrics. As materials engineering advances and microstructures become more sophisticated, more adaptable and customized measurements are required for novel materials characterization. Furthermore, development and popularization of novel electronics such as flexible and wearable devices expands the need for more adaptable thermal management techniques. Therefore, advanced techniques for integrated temperature management is needed to better characterize, monitor and control the functioning of modern devices as well as future generation of novel and wearable devices.There are two main components for integrated thermal management, passive sensing and active cooling. As the size of transistors reduces and gets close to the physical limit of the Moore's law, nanoscale thermometry or high resolution of temperature measurement down to the component-level or gate-level is desired to monitor the distributions of hot spots and optimize performance for modern computer chips, memory caches, and multicore processors. Another essential component of integrated thermal management is active cooling. Novel materials such as transverse thermoelectrics with perpendicular directions of heat flow and electrical current flow require only a single leg for full thermoelectric function, making them promising candidates for critical cooling elements in integrated thermal management. Transverse thermoelectrics and high-speed device materials like $mathrm{Ga_2O_3}$, have anisotropic crystal structure and therefore anisotropic thermal conductivity, and new characterization methods are required to accurately and rapidly measure the thermal conductivity anisotropy. Moreover, flexible fabrics are yet another high-impact conformal geometry for active cooling for thermal management. Conformal active Peltier cooling flexible fabrics would enable a whole new generation of thermal management applications.For passive sensing with high resolution thermometry, thin film thermocouples (TFTC) are of interest because they are simple for fabrication, highly accurate and fast in response, requiring no power input. However, the scalability of TFTCs is not well studied, and prior works of TFTCs are limited to either single-pair thermocouple measurements or a simple stack of TFTCs in arrays. We fabricated gthin film thermocouples (TFTC) at the microscale and used TFTCs perpendicular to each other with separation distances of 20-100 si{micro}m to create a 2D thermal gradient mapping with a single pair of TFTCs. By designing all thermocouple junctions to be local to the array, we were able to eliminate thermal fluctuation issues that plagued previous proposed TFTC array designs. The smallest detectable temperature difference is 10 mK, and the sensitivity is 0.5 mK/si{micro}m. This device can be applied for embedded thermal management systems that require high resolution and rapid-response thermal management, such as stacked three-dimensional (3D) integrated circuits.For active cooling wit
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