Characterization of SiCN thin films: Experimental and theoretical investigations

Review—Silicon Nitride and Silicon Nitride-Rich Thin Film Technologies: Trends in Deposition Techniques and Related Applications

“…Alternatively, the pre-adsorption reactions in the case of PA-CVD or PE-CVD could produce more active reactant species, leading to higher surface reaction rates at shorter surface diffusion lengths, potentially producing less contaminated SiN x films but with poorer step coverage and lower etch resistance. 107 Although a significant body of research in thermal CVD SiN x can be found in the literature prior to 2010, 73,105,106,[111][112][113][114][115] there are very few recent reports (within the last five years) on the topic, due most likely to the high thermal budget required for dissociation and reaction of the Si and N chemistries, except for 34 included the use of pulsed RF generated by modulating a continuous 200Hz low-frequency wave signal generator with 50% duty cycle in the PE-CVD reaction of SiH 4 and NH 3 at 150…”

“…It was determined that the bare Si=N sites were more energetically favorable than their NH/SiH and NH/SiNH 2 counterparts to react with the Si or Cl atoms from the source precursors. It was also concluded that the reaction energy was lower for Si 2 Cl 6 than SiH 4 . These findings led to the identification of a 3 step PE-ALD process to attain the most energetically favorable surface sites during the Si source PE-ALD substrate exposure step.…”

“…82 Another investigation 11 also explored the role of a N 2 plasma pre-treatment prior to the SiH 4 exposure step on Si substrates and found that atomic N and N + are the central reactant species that adsorb to the Si surface to form Si-N. The latter then act as reactive adsorption spots for SiH 4 at N dangling bond sites, generating adsorbed SiH x and NH x species. Further adsorption is excluded until subsequent exposure to the N 2 plasma, leading to a repetition of the previous N species adsorption cycle.…”

“…Traditionally, SiN x deposition, particularly in IC devices, utilized Si-and N-rich precursors such as SiH 4 and N 2 in relatively high-energy environments (>700…”

“…15,16 In an analogous manner, SiN x and SiC y thin films are successfully incorporated into active optical and optoelectronic devices due to their wide bandgap (2.3 eV for SiC y and 5.1 eV for SiN x ), and elevated electrical breakdown voltage, including panel displays, lighting, and light-emitting devices. 4,[17][18][19] In this respect, both types of Si-based coatings are employed as permeation barriers and encapsulation layers in light-emitting devices (LEDs), and organic LEDs (OLEDs), [20][21][22][23] as well as in the fabrication of various planar optical systems and optical waveguides. 24 Additionally, SiN x C y and SiN x coatings are used or suggested as passivation layers in flexible electroluminescent devices.…”