Bosch says that its new microchips made of silicon carbide (SiC) have better electrical conductivity compared to the silicon chips used to date.
“Silicon carbide semiconductors bring more power to electric motors. For motorists, this means a 6% increase in range,” said Harald Kröger, member of the Bosch board of management. Bosch manufactures the new generation of semiconductor chips at its Reutlingen plant, 25 miles south of Stuttgart. At this plant, the company has been turning out several million microchips every day for decades.
The company says that semiconductors made of silicon carbide set new standards for switching speed, heat loss, and size. In power electronics, they ensure that 50% less energy is lost in the form of heat. This saving translates into more efficient power electronics and more energy for the electric motor and, therefore, for the battery range. In this way, Bosch says it is addressing both range anxiety with consumers and battery size for manufacturers.
The reason is that the new technology also offers further potential savings down the line: the much lower heat losses of the chips, combined with their ability to work at much higher operating temperatures, mean that manufacturers can cut back on the expensive cooling of the powertrain components. That has a positive impact on electric vehicles’ weight and cost.
Turning the circular discs of silicon or silicon carbide—the wafers—into semiconductor chips involves an elaborate manufacturing process that can last up to 14 weeks. In several chemical and physical processes, the wafers acquire ultra-fine structures that will subsequently make up the tiny chips, each of which measures just a few millimeters. Its manufacturing operations in Dresden will use wafers with a diameter of 300 mm. This means significantly more chips from a wafer, and correspondingly greater economies of scale than with semiconductors based on 150- and 200-mm technology. Bosch produces the latter in Reutlingen, where it will also manufacture the new SiC chips.
“Semiconductors are a core component of all electrical systems. They are also turning data into a coveted raw material of the future. As they are becoming increasingly important in our fields of activity, we want to continuously expand our manufacturing operations,” Kröger says. The first associates are due to start work in the spring of 2020. Bosch will operate the plant as a carbon-neutral site.