Crystallization and activation of silicon by microwave rapid annealing

A combination of the carbon-powder absorber with microwave irradiation is proposed as a rapid heat method. 2-μm-diameter carbon powders with a packing density of 0.08 effectively absorbed 2.45 GHz 1000-W-microwave and heated themselves to 1163 °C for 26 s. The present heat treatment recrystallized n-type crystalline silicon surfaces implanted with 1.0 × 10 15 -cm - 2 -boron and phosphorus atoms with crystalline volume ratios of 0.99 and 0.93, respectively, by microwave irradiation at 1000 W for 20 s. Activation and carrier generation were simultaneously achieved with a sheet resistivity of 62 Ω / sq . A high photo-induced-carrier effective lifetime of 1.0 × 10 - 4 s was also achieved. Typical electrical current-rectified characteristic and solar cell characteristic with an efficiency of 12.1 % under 100 -mW/cm 2 -air-mass- 1.5 illumination were obtained. Moreover, heat treatment with microwave irradiation at 1000 W for 22 s successfully crystallized silicon thin films with thicknesses ranging from 2.4 to 50 nm formed on quartz substrates. Nano-crystalline cluster structure with a high volume ratio of 50 % was formed in the 1.8-nm (initial 2.4-nm)-thick silicon films. Photoluminescence around 1.77 eV was observed for the 1.8-nm-thick silicon films annealed at 260 °C in 1.3 × 10 6 -Pa-H 2 O-vapor for 3 h after the microwave heating.