Si-containing film forming precursors and methods of using the same

Methods for producing halosilazane comprise halogenating a hydrosilazane with a halogenating agent to produce the halosilazane, the halosilazane having a formula(SiHa(NR2)bXc)(n+2)Nn(SiH(2−d)Xd)(n−1),wherein each a, b, c is independently 0 to 3; a+b+c=3; d is 0 to 2 and n≥1; wherein X is selected from a halogen atom selected from F, Cl, Br or I; each R is selected from H, a C1-C6 linear or branched, saturated or unsaturated hydrocarbyl group, or a silyl group [SiR′3]; further wherein each R′ of the [SiR′3] is independently selected from H, a halogen atom selected from F, Cl, Br or I, a C1-C4 saturated or unsaturated hydrocarbyl group, a C1-C4 saturated or unsaturated alkoxy group, or an amino group [-NR1R2] with each R1 and R2 being further selected from H or a C1-C6 linear or branched, saturated or unsaturated hydrocarbyl group, provided that when c=0, d≠0; or d=0, c≠0.