A polyester film comprises a polyester (A) composed mainly of polybutylene terephthalate and a polyester (B) composed mainly of polyethylene terephthalate, wherein a mass ratio (A/B) between the polyesters (A) and (B) is 70/30 to 55/45, a dry heat shrinkage rate (A) through heat treatment at 160 C. for 30 minutes is 20% or less in any of four directions on a film surface (0, 45, 90 and 135), a difference between a maximum value and a minimum value of these dry heat shrinkage rates is 5% or less, a dry heat shrinkage rate (B) through heat treatment at 200 C. for 15 minutes is 35% or less in any of the four directions, a difference between a maximum value and a minimum value of these dry heat shrinkage rates is 5% or less, and a thickness variation in the four directions is 10% or less.

Amino-functionalized linear and cyclic oligosiloxanes, which have at least two silicon and two oxygen atoms as well as an organoamino group and methods for making the oligosiloxanes are disclosed. Methods for depositing silicon and oxygen containing films using the organoamino-functionalized linear and cyclic oligosiloxanes are also disclosed.