Simulation study of SiH₄ microdischarges in a narrow channel

Using the Particle-in-Cell/Monte Carlo (PIC/MC) method, the behavior of SiH₄ plasma discharge in a narrow channel was studied. Simulations were carried out at a gas pressure of 5 Torr for an electrode distance of 20 mm and a narrow channel with an inner diameter of 2 mm. Most SiH₂ ⁺ ions were found to be changed into SiH₃⁺ ions due to SiH₂⁺-SiH₄ collisional charge exchange. The dominant charged species in the discharge were electrons and SiH ₃⁺ ions. The inner surface of the narrow channel greatly affected SiH₄ plasma behavior due to an accumulation of charged particles. An intense ionization rate was found for the first time in the sheath on the inner surface of the narrow channel. The largest electron and SiH ₃⁺ ion densities appeared at the edge of the plasma bulk abutting the sheath on the inner surface of the narrow channel.