This paper reports the electrical, mechanical, structural and field emission properties of as grown and also boron and phosphorous incorporated tetrahedral amorphous carbon (ta-C) films, deposited using a filtered cathodic vacuum arc process. The effect of varying boron and phosphorous content (up to 2.0 at.% in to ta-C) on the conductivity (sigma(D)), activation energy (Delta E-1), hardness, microstructure, emission threshold (Eturn-ON) and emission current density (J) at 12.5 V/mu m of ta-C: B and ta-C: P films deposited at a high negative substrate bias of -300V are reported. It is observed that both boron and phosphorous incorporation leads to a nearly an order increase in sigma(D) and corresponding decrease in Delta E-1 and a slight increase in hardness as compared to as grown ta-C films. In the case of field assisted electron emission, it is observed that Eturn-ON increases and J decreases. The changes are attributed to the changes in the sp(3)/sp(2) ratio of the films due to boron and phosphorous incorporation. The effect of boron on ta-C is to give a p-type effect whereas the effect of phosphorous gives n-type doping effect. (C) 2010 Published by Elsevier B. V.