  The behavior of a charged scalar field in the RN black hole space time is
studied using WKB approximation. In the present work it is assumed that matter
waves can get reflected from the event horizon. Using this effect, the Hawking
temperature and the absorption cross section for RN black hole placed in a
charged scalar field are calculated. The absorption cross section $\sigma
_{abs}$ is found to be inversely proportional to square of the Hawking
temperature of the black hole.
