Hot carrier internal thermionic photoemission in pulsed CO2 -laser-excited n+-p silicon junctions

Experimental and theoretical studies were carried out on the electrical response of a forward biased n⁺-p silicon junction under photoexcitation with high-intensity 60-ns laser pulses at λ=10.6 μm. The observed strong bias-dependent electrical pulses are associated to changes in the junction forward current due to the carriers of the high energy tail within the photoexcited hot-electron distribution. A thermionic emission model of hot electrons over the junction barrier account for the experimental results. According to this model and the measured electrical response, the temperature of the carriers is nearly 100 K higher than the lattice temperature, which essentially remains constant at room temperature