We have searched for direct production of scalar top quarks at the Collider
Detector at Fermilab in 88 pb(-1) of p (p) over bar collisions at root s =
1.8 TeV. We assume the scalar top quark decays into either a bottom quark
and a chargino or a bottom quark, a lepton, and a scalar neutrino. The even
t signature for both decay scenarios is a lepton, missing transverse energy
, and at least two b-quark jets. For a chargino mass of 90 GeV/c(2) and sca
lar neutrino masses of at least 40 GeV/c(2), we find no evidence for scalar
top production and present upper limits on the production cross section in
both decay scenarios.