Silicon-rich low thermal budget silicon nitride for integrated circuits

A low-thermal budget, silicon-rich silicon nitride film may include a concentration of hydrogen in Si-H bonds being at least 1.5 times as great as a concentration of hydrogen in N-H bonds. The silicon nitride film suppresses boron diffusion in boron-doped devices when such devices are processed using high-temperature processing operations that conventionally urge boron diffusion. The low-thermal budget, silicon-rich silicon nitride film may be used to form spacers in CMOS devices, it may be used as part of a dielectric stack to prevent shorting in tightly packed SRAM arrays, and it may be used in BiCMOS processing to form a base nitride layer and/or nitride spacers isolating the base from the emitter. Furthermore the low-thermal budget, silicon-rich silicon nitride film may remain covering the CMOS structure while bipolar devices are being formed, as it suppresses the boron diffusion that results in boron penetration and boron-doped poly depletion.