We investigated the effect of boron dosage and post-thermal budget on the electrical properties such as capacitance-voltage (C-V), gate leakage current-voltage (I-V), and charge-to-breakdown (QBD) of metal oxide semiconductor (CMOS) capacitors with W/WNx/poly-Si1-xGex gates stack. The C-V curve of the MOS-capacitors with the W/WNx/poly-Si0.4Ge0.6 stack had a lower flatband voltage (VFB) and showed less gate depletion effect (GDE), compared with that of the W/WNx/poly-Si0.8Ge0.2 stack due to the decrease of gate electrode work function and the increase of dopant activation rate with the increase of Ge content, respectively. Although the I-V curves of MOS-capacitors with W/WNx/poly-Si1-xGex gates stack exhibited similar behaviors regardless of Ge content, the beginning of conduction in the I-V curves accelerated with the increase of Ge content due to the decrease of the gate electrode work function. The QBD of W/WNx/poly-Si0.4Ge0.6 gates stack was much higher than that of the W/WNx/poly-Si gates stack due to the reduced boron penetration in the gate oxide. We also found that annealing temperatures between 800 and 850°C has no influence on the electrical properties of MOS capacitors with W/WNx/poly-Si1-xGex gates stack.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry