Abstract: Methods of efficiently and accurately heating a semiconductor device in a standard (i.e. room temperature) handler are provided. In one embodiment, an infrared light source can be focused on the device to heat its chip. In another embodiment, the substrate diode in the device can be forward biased to heat the chip. Advantageously, the forward voltage of the substrate diode has a direct relationship with chip temperature. This relationship can be determined based on a characterization of an exemplary device type. Therefore, measuring the forward voltage can provide an accurate derivation of chip temperature. Heating of the device using a focused light source or substrate diode can be done immediately prior to testing, thereby providing an extremely time efficient way to test the device under high temperature conditions.