Using the particular benefits of Focused Electron Beam Irradiation (FEBI) junctions, such as on chip modification of the barrier resistivity through controlled variation of the electron fluence and annealing, we show that the conventional model for SNS junctions as derived by De Gennes can explain the their behavior in great detail. Due to the high defect concentration produced by the electron beam, the barrier material is non-superconducting and has a much higher normal state resistivity than undamaged YBa_2Cu_3O_(7-#delta#). From the exponential scaling of the critical current (I_c) with the square root of the resistance (R_n) it is shown that FEBI junctions have a dirty limit SNS character and that the carrier mass in the irradiated material is of the order of m_e.
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