Exact analytical solution to the Poisson-Boltzmann equation for semiconductor devices Elyas Shivanian, Saeid Abbasbandy and Mohammed S. Alhuthali Eur. Phys. J. Plus, 129 6 (2014) 104 Published online: 02 June 2014 DOI: 10.1140/epjp/i2014-14104-5