Growth processes of particles in high frequency silane plasmas are studied as a parameter of discharge frequency (3.5–28 MHz) or by modulating the amplitude of discharge voltage (125–275 V). Except for the 28 MHz case, particles tend to grow through three phases of nucleation and subsequent initial growth, rapid growth, and growth saturation. A detailed study for 6.5 MHz explains the following features: morphology of particles shows that coagulation of particles plays a crucial role in the rapid growth phase; a coagulation rate of 200 s−1 observed in the rapid growth phase is extremely high compared to a thermal collision rate of 5 s−1 between particles; coagulation almost stops when decreasing the discharge power by about one-fourth at the middle of the rapid growth phase; two size groups of particles with narrow size dispersions coexist during and after the rapid growth phase. For 28 MHz, while, as compared to 6.5 MHz, particles appear early after the initiation of discharge and their density is high by about two orders, their growth rate in the subsequent phase is quite low. To properly explain most rapid growth features, a model, taking into account coagulation between oppositely charged particles, is proposed.

Particle growth processes and the contribution of short lifetime radicals to the processes in SiH4 high frequency plasmas for a moderately high power above 0.25 W/cm2 are studied using polarization-sensitive laser light scattering, a newly developed Langmuir probe, a novel photodetachment, transmission electron microscopy, atomic force microscopy, and intracavity laser absorption methods together with a discharge modulation method. Particles are generated and grow from their nucleation phase principally around the plasma/sheath boundary near the powered electrode. Spatial profiles of the particle amount are very similar to those of production rates and densities of short lifetime radicals. The SiH2 density is low in spite of its high production rate. While the SiH2 density in the early discharge stage for 28 MHz is about one order higher than that for 6.5 MHz, the particle density for 28 MHz is two orders higher than that for 6.5 MHz. These results suggest that short lifetime radicals, in particular SiH2 radicals, not only participate mainly in the particle nucleation but also contribute numerous times to the nucleation and subsequent initial growth reactions of one particle. Moreover, photodetachment measurements showed that clusterlike particles exist even in the bulk plasma; some of them are considered to be neutral and hence they are likely to be transported to the substrate on the grounded electrode.

The effects of rapid thermal annealing (RTA) performed after source/drain (S/D) implantation on the characteristics of complementary metal-oxide-semiconductor (CMOS) transistors with a TiN metal gate were investigated thoroughly. It was shown that n-channel devices require a higher thermal budget in order to reduce junction leakage, compared to p-channel devices. It was also found that the flat-band voltage and oxide thickness are both affected by the annealing temperature, particularly for p-channel devices. In n-channel devices, the gate leakage current level is highly dependent on channel length and RTA temperatures. Further analysis indicated that the agglomeration phenomenon during the high-temperature RTA step occurs more easily as the metal gate length becomes narrower. When this happens, gate oxide integrity is degraded, resulting in an increased gate leakage of n-channel transistors.

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