Onsemi said on Wednesday it would buy GT Advanced Technologies, a manufacturer of a key material used in chips for electric vehicles called silicon carbide, for $415 million in cash. The move is a major push further into electric vehicles for Onsemi, which already supplies other automotive chips such as sensors in driver safety systems. Automakers are turning to chips made from silicon carbide for the drivetrains and charging systems in electric vehicles because the material is more energy-efficient than chips made from standard silicon. But the crystalline material requires new techniques to produce and to manufacture compared to standard silicon. To make silicon carbide chips, companies like Onsemi must use raw discs called wafers. The silicon carbide versions of those wafers come from a only few key suppliers such as Cree Inc, which has shifted its strategy from LED chips used in lighting to focus on silicon carbide chips …