Copolymerized polysilazane, manufacturing method therefor, composition comprising same, and method for forming siliceous film using same

A method for manufacturing a copolymerized polysilazane

• wherein the copolymerized polysilazane comprises at least a repeating unit represented by the formula (I) below and a repeating unit represented by the formula (II) below and has a NR3/SiH1,2 ratio of 0.005 to 0.3, wherein SiH1,2 represents the total amount of SiH1 and SiH2,
• wherein
• R1 and R2 each independently represents a hydrogen atom, a hydrocarbon group, a hydrocarbon group-containing silyl group, a hydrocarbon group-containing amino group, or a hydrocarbon oxy group and
• R3 represents an alkyl group, an alkenyl group, an alkoxy group, a cycloalkyl group, an aryl group, or an alkyl silyl group,
• wherein R1 and R2 represent the same meanings as above and wherein the copolymerized polysilazane has a SiH3/SiH1,2 ratio in the range of 0.05 to 0.4,
• which comprises reacting a dihalosilane compound represented by the formula (III):
• in which, R1 and R2 each independently represents a hydrogen atom, a hydrocarbon group, a hydrocarbon group-containing silyl group, a hydrocarbon group-containing amino group, or a hydrocarbon oxy group, and X represents F, Cl, Br, or I,
• with a primary amine compound represented by the formula (IV):
• R3—NH2 (IV)
• in which, R3 represents an alkyl group, an alkenyl group, an alkoxy group, a cycloalkyl group, an aryl group, or an alkyl silyl group,
• and then reacted with ammonia.