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Another key property is thermal conductivity, which indicates how easy it is to extract the heat generated by power losses in the semiconductor device and thereby prevent the operat- ing temperature of the device from rising dangerously. For semiconductor-based devices with low thermal conductiv- ity, such as silicon, it is more difficult to keep the operating temperature low. For this purpose, an operating mode known as de-rating was adopted that intentionally introduces a par- tial degradation of performance to avoid compromising the component at high temperatures. Conversely, a high thermal conductivity ensures that the device can be cooled adequately without introducing any degradation in performance.
The SiC device technology offered by GeneSiC plays a key role in achieving high levels of efficiency in numerous power applications.
SiC is capable of operating at a temperature of at least 200˚C, which is 50˚C higher than the typical junction tem- perature of silicon MOS devices. For many SiC devices, this temperature can be as high as 400˚C or higher. This prop- erty allows SiC power devices to operate efficiently even at high temperatures, avoiding performance de-rating and reduction of mean time to failure, with improvement in terms of quality and reliability.
“Our products are all made with a very advanced thermal management packaging technology; for example, all of our products, except for DO-214 [SMD] packages, are made with Ag [silver] sintering,” said Singh.
Silver sintering is a die-attach and bonding technology, which offers a void-free and strong bond with superior thermal and
electrical conductivity. Ag sintering can decrease the junction temperature (TJ) of an electronic device up to 100˚C.
Figure 2 shows an n-channel enhancement-mode GeneSiC SiC MOSFET whose VDS = 1.2 kV, RDS(on) = 20 mΩ, and ID = 65 A. The device is suitable for power applications such as EV fast charging, solar inverters, smart grids, industrial inverters and motor drives, and transportation.
SiC design considerations
Even if silicon can satisfy most of the current needs in the field of power electronics, its chemical-physical proper- ties limit its performance at high temperatures and high working voltages. To ensure proper device operation under these conditions, GeneSiC offers SiC-based devices such as MOSFETs, transistors, Schottky diodes (including those with merged-pin-Schottky, or MPS, designs), PIN diodes, and junction transistors. Over the past few years, the struc- ture and manufacturing process of SiC devices have been perfected, solving some operational and reliability aspects, including those related to the reliability of the gate oxide in SiC MOSFETs.
FIGURE 2: GENESIC 1.2-KV SiC MOSFET
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AspenCore News Coverage SiC Drives Innovation in Power Applications