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This article introduces a silicon carbide (SiC)-based high-voltage silicon-controlled rectifier (HV-SCR) for on-chip electrostatic discharge (ESD) protection. The SiC HV-SCR is formed by implanting a $\text{p}^{+}$ region into the n-well of SiC laterally diffused metal-oxide semiconductor (LDMOS) structures. Both LDMOS and HV-SCR structures were characterized using a transmission line pulse (TLP) system to investigate their ESD behaviors. The TLP measurement results show that the trigger voltage (${V}_{\text {t1}}$) of the SiC HV-SCR is $\sim 230$ V and has minor dependence on the drift length. The ${V}_{\text {t1}}$ value of the SiC LDMOS decreases from 224 to 202 V when its drift length decreases from 6 to 4 $\mu \text{m}$. TLP measurements with 500- $\Omega $ impedance were conducted to obtain an accurate holding voltage (${V}_{\text {h}}$) and failure current (${I}_{\text {t2}}$) of HV-SCR and LDMOS. Relatively high ${I}_{\text {t2}}$ (i.e., 33 mA/ $\mu \text{m}$) of the HV-SCR structure was observed, which is much stronger than the LDMOS structure (i.e., 0.2 mA/ $\mu \text{m}$). The ${V}_{\text {t1}}$ and ${V}_{\text {h}}$ values of HV-SCR were also investigated with varying gate bias voltages. Moreover, technology computer-aided design (TCAD) simulations of the SiC HV-SCR and LDMOS were carried out to further understand their ESD behaviors. [ABSTRACT FROM AUTHOR]

This paper presents functional high-temperature analog circuits in silicon carbide bipolar technology. The circuits will collectively form the analog signal conditioning block for a wireless telemetry system in an extreme environment (above 400°C). The signal conditioning block is composed of a low dc gain operational amplifier, a negative voltage charge pump (CP), an RC oscillator, and a voltage regulator. The circuits are tested up to 450°C. The measured open-loop gain for the amplifier at 450°C is 30 dB. The regulator provides approximately 9-V output at 450°C for a fixed load current of up to 18 mA and an applied reference of 4.5 V. The negative voltage CP requires an oscillating signal at its input, which is provided by the RC cross-coupled oscillator. The CP provides about −5 V at 450°C. [ABSTRACT FROM AUTHOR]

This paper describes a silicon carbide pulse width modulation (PWM) signal generator in the 1.2 μm HiTSiC CMOS process developed by Raytheon Systems Ltd. The design features a 6-b binary input, which allows for setting a system's duty cycle. The results presented in this paper utilize a field programmable gate array board in the test setup to dynamically set the duty cycle by controlling each bit. A control current is also available to give the user added flexibility for tuning the duty cycle. Experimental results show the duty cycle range of the PWM generator to be between 4.7% and 95.2% at 400 °C. Sustained operation of the circuit is demonstrated over a period of 50 h at 300 °C. Finally, the PWM generator is evaluated in the operation of a boost converter. [ABSTRACT FROM PUBLISHER]

In the last decade, significant effort has been expended toward the development of reliable, high-temperature integrated circuits. Designs based on a variety of active semiconductor devices including junction field-effect transistors and metal-oxidesemiconductor (MOS) field-effect transistors have been pursued and demonstrated. More recently, advances in low-power complementary MOS (CMOS) devices have enabled the development of highly integrated digital, analog, and mixed-signal integrated circuits. The results of elevated temperature testing (as high as 500°C) of several building block circuits for extended periods (up to 100 h) are presented. These designs, created using the Raytheon UK's HiTSiC® CMOS process, present the densest, lowest-power integrated circuit technology capable of operating at extreme temperatures for any period. Based on these results, Venus nominal temperature (470°C) transistor models and gate-level timing models were created using parasitic extracted simulations. The complete CMOS digital gate library is suitable for logic synthesis and lays the foundation for complex integrated circuits, such as a microcontroller. A 16-bit microcontroller, based on the OpenMSP 16-bit core, is demonstrated through physical design and simulation in SiC-CMOS, with an eye for Venus as well as terrestrial applications. [ABSTRACT FROM AUTHOR]