when a pn junction diode is forward biased, the electrons in n-region get attracted towards the p-region. after it crosses the the juction it recombines with the holes and thereafter under the influence of the applied bias voltage, it jumps from vacancies to vacancies thereby creating movement of holes. but how does depletion region gets narrowed. there is negative ions present in p-region which should get attracted to the positive terminal of the battery. so the depletion region width should increase.?????