Integrated Digital and Analog Circuit Blocks in a Scalable Silicon Carbide CMOS Technology

Abstract

The wide bandgap of silicon carbide (SiC) has attracted a large interest over the past years in many research fields, such as power electronics, high operation temperature circuits, harsh environmental sensing, and more. To facilitate research on complex integrated SiC circuits, ensure reproducibility, and cut down cost, the availability of a low-voltage SiC technology for integrated circuits is of paramount importance. Here, we report on a scalable and open state-of-the-art SiC CMOS technology that addresses this need. An overview of technology parameters, including MOSFET threshold voltage, subthreshold slope, slope factor, and process transconductance, is reported. Conventional integrated digital and analog circuits, ranging from inverters to a 2-bit analog-to-digital converter, are reported. First yield predictions for both analog and digital circuits show great potential for increasing the amount of integrated devices in future applications.

Esaki Diode Behavior in Highly Uniform MoS2/Silicon Carbide Heterojunctions

“…Owing to its outstanding physical properties (wide bandgap, high‐critical electric field, and thermal conductivity) [ 15 ] and high technological maturity, the 4H‐SiC polytype is nowadays the material of choice for high‐power devices, which are crucial in strategic fields (energy conversion systems, electric vehicles, and trains, ..) for modern economy and society. [ 16 ] Recently, silicon carbide is also attracting increasing interest for the fabrication of complementary metal oxide semiconductor circuits able to operate at high temperatures and in harsh or radiation environments, [ 17 ] where conventional Si devices fail. The hexagonal SiC polytypes (6H‐ and 4H‐SiC) naturally support the epitaxial growth of 2D materials with hexagonal lattice, including graphene and transition metal dichalcogenides (TMDs).…”

Visible Blind Quadrant Sun Position Sensor in a Silicon Carbide Technology

“…The photodetectors are implemented in the novel open silicon carbide CMOS technology [9][10][11] developed by Fraunhofer IISB in Germany. The fabrication process front-end-of-line (FEOL) is implemented by ion implantation, which is used for the photodetector realization.…”

“…Unfortunately, the HiTSiC technology was discontinued in 2018, which left the need for a new and open SiC CMOS technology. This need is addressed by the recent development of the SiC CMOS at Fraunhofer IISB [9][10][11]. This work reports on a quadrant sun position sensor in 4H-SiC (Figure 1), which builds on the previously reported integrated 3D optics approach [12] to aim for miniaturization of the device in the future.…”

Resistive and CTAT Temperature Sensors in a Silicon Carbide CMOS Technology

“…Fig. 1 Photograph of the multi-project four inch silicon carbide device wafer, fabricated in the Fraunhofer IISB SiC CMOS technology [20]. The field of wide bandgap semiconductors has gained increased research interest over the past decades.…”

“…A vertical p-i-n diode temperature sensor is already reported in this technology [21] and has a sensitivity of 2.3-3.4mV/K for a wide operating range and shows excellent linearity. This work reports on temperature sensing in the state-ofthe art 6 µm 4H-SiC CMOS technology [20], developed by Fraunhofer IISB. The temperature coefficient of resistance of highly doped layers is characterized up to 200 °C and compared to a circuit-based temperature sensor in a similar range.…”