Resistive and CTAT Temperature Sensors in a Silicon Carbide CMOS Technology

Abstract

Accurately sensing the temperature in silicon carbide (power) devices is of great importance to their reliable operation. Here, temperature sensors by resistive and CMOS structures are fabricated and characterized in an open silicon carbide CMOS technology. Over a range of 25-200°C, doped design layers have negative temperature coefficients of resistance, with a maximum change of 79%. Secondly, CMOS devices are used to implement a CTAT, which achieves a maximum sensitivity of 7.5mV/K in a temperature range of 25-165°C. The integration of readout electronics and sensors that are capable of operation in higher temperature than silicon, opens application in harsher environments.

Visible Blind Quadrant Sun Position Sensor in a Silicon Carbide Technology

“…By implementing the visible blind sun position sensor in this silicon carbide technology, future implementations can integrate CMOS readout circuitry on-chip to achieve high performance sensors that can outperform the state-of-the-art in industry. Furthermore, such opto-electronic integration enables other detector architectures, like a scalable array of active pixels [13], and even additional functionalities such as temperature sensing [14][15]. The collimating sun position sensor is implemented by alignment of a sapphire optical window to the silicon carbide device on chip level.…”

A 4H-SiC CMOS Oscillator-Based Temperature Sensor Operating from 298 K up to 573 K

“…Up to now, both unipolar and bipolar 4H-SiC IC technologies have been developed: on bipolar technology, a Bipolar Junction Transistor based on multi-epitaxial stacks is used in analog [ 4 , 5 , 6 ] and digital [ 7 ] ICs, and its performance has been demonstrated up to 873 K. The 4H-SiC Complementary Metal Oxide Semiconductor Field Effect Transistor, CMOS technology proposed by Raytheon, has been developed, and analog and digital building blocks have been fabricated [ 8 ], such as, for example, a Positive-To-Absolute-Temperature (PTAT) circuit in the range between 298 K and 573 K, and with a maximum deviation from the ideal linear curve of [ 9 ]. Recently, Fraunhofer IISB provided a 4H-SiC 2 m-CMOS technology [ 10 ] and several ICs have been proposed, like CMOS Complementary-To-Absolute-Temperature (CTAT), a sensor in the range between 298 K and 438 K and with a sensitivity of 7.5 mV/K [ 11 ], or a temperature sensor based on a p-n diode from 297 K and 873 K, with an of the voltage-temperature characteristic. Moreover, such technology is also compatible with other device structures that are useful for sensing temperature and ultraviolet radiation [ 12 ].…”

“…All the 4H-SiC-based proposed temperature sensors transduce temperature in electrical quantities, either through the difference of Gate Source Voltages ( ) between two MOSFETs [ 11 ], or through the difference of diode forward voltages [ 2 , 3 , 9 , 13 , 14 ]. However, 4H-SiC diodes with good performances have vertical structures and they are incompatible with VLSI circuits, whereas, although MOSFETs can be used, they need an integrated circuit in order to read out the voltage-temperature signal.…”