Oxygen, boron, and phosphorus additions to polysilicon films were followed up to 23% oxygen. Above 500 Omega/square, oxygen resulted in temperature coefficients of resistivity (TCR) magnitudes a factor of two smaller than without oxygen. For p-type films, the TCR saturated at similar to0.05% for low resistivities. Surface energy considerations show that the oxygen atoms are likely to attach to the surface of the growing grains. This explains the dependence on oxygen concentration of grain size, boron segregation, and tunneling barrier. A model for polysilicon resistivity was used to study changes with added oxygen and dopants. The potential barrier was followed down to a saturation region. The latter was found to be independent of oxygen, but to depend on carrier concentration and type according to the U-shaped trap distribution in oxygen-free films. This is also responsible for the saturation in the TCR. The f factor showed temperature-independent tunneling to gradually outweigh the temperature-dependent contribution from the potential barrier. A dopant-dependent f factor showed that dopant scattering begins to dominate over tunneling. Boron segregation in oxygen-rich films was 30-35%. Boron gave rise to a slight increase in grain size and phosphorus gave rise to a large increase. There were significantly more charged traps in films containing oxygen, where they exceeded 10(13) cm(-2).