APPENDIX A
            FABRICATION PROCEDURES AND TEST STRUCTURES


     This appendix contains a list of the fabrication procedures

followed-to generate the test structures measured in this study. These test structures were part of NBS-4 [67] test pattern, and include a planar four-probe collector resistor, a 100 mil square Hall effect device, a gated base-collector diode, and a gated MOS capacitor over collector structure.


A.1  Initial Si0,2 Masking:

     A.la Initial Clean Up:

            (1) Ultrasonic clean in hot DI water with small amount of

                100 Tritonex solution for 10 minutes.

            (2) Rinse in'running DI water for 5 minutes.

            (3)  Place in solution of lNH 4OH:1H202:2H 20 for 20 minutes

                 at 50 degrees C.

            (4)  Rinse in DI water for 5 minutes.

            (5)  Dip in 10 percent.HF for 10 seconds.

            (6)  Rinse in DI water for 5 minutes.

            (7)  Place in solution of lHCl:1H202 :2H 20 for 20 minutes at

                 50 degrees C.

            (8)  Rinse in DI water for 10 minutes and spin dry in N2.

     A.lb   Initial Oxidation - 350 nm at 1100 degrees C

            (1)  Push-in         5 minutes           N2 at 1000 cc/minute