The design, fabrication technology and parameters are presented for monolithic linear 16-element IR emitter bar and the 8 x 8 stack of bars. Both types of devices are based on the Si p + in + -diodes with the 0.86 x 0.86 mm 2 emitting surface integrated into a single chip and operated at well above room temperatures by the contact double injection of free charge carrier. To bypass Si electronic band structure limitation, we utilized free carrier absorption as a way to monitor material below-bandgap IR thermal emission. At a device temperature T=453 K, nearly 1.0 mW output power and 420 K apparent temperature of IR (3 to 12 µm spectral band) radiation could be achieved with ~0.8% external power efficiency and 0.1 ms rise-fall time. This represents the longer wavelengths, higher operating temperatures and output power from Si spontaneous emitters ever reported.