  We present the results of a search for pair production of scalar top quarks in an R-parity violating supersymmetry scenario in 106 pb-1 of ppbar collisions at $\sqrt{s} = 1.8$ TeV collected by the Collider Detector at Fermilab. In this mode each scalar top quark decays into a tau lepton and a b quark. We search for events with two tau's, one decaying leptonically (e or mu) and one decaying hadronically, and two jets. No candidate events pass our final selection criteria. We set a 95% confidence level lower limit on the scalar top quark mass at 122 GeV/c2 for Br (stop-> tau + b) = 1. 
Search For Pair Production of Scalar Top Quarks in R-parity Violating   Decay Modes in ppbar Collisions at sqrt{s} = 1.8 TeV