  In Witten's open cubic bosonic string field theory and Berkovits' superstring
field theory we investigate solutions of the equations of motion with
appropriate source terms, which correspond to Callan-Maldacena solution in
Born-Infeld theory representing fundamental strings ending on the D-branes. The
solutions are given in order by order manner, and we show some full order
properties in the sense of (alpha)'-expansion. In superstring case we show that
the solution is 1/2 BPS in full order.
