  We use the lattice model of directed walks to investigate the conformational
as well as the adsorption properties of a semiflexible homopolymer chain
immersed in a good solvent in two and three dimensions. To account for the
stiffness in the chain we have introduced energy barrier for each bend in the
walk and have calculated the persistent length as a function of this energy.
For the adsorption on an impenetrable surface perpendicular to the preferred
direction of the walk we have solved the model exactly and have found the
critical value of the surface attractions for the adsorption in both two and
three dimensions. We have also enumerated all the possible walks on square and
cubic lattices for the number of steps N <= 30 for two-dimensions and N <= 20
for three dimensions and have used ratio method for extrapolation. The
transition located using this method is in excellent agreement with the results
found from the analytical method.
