5 Depth, Range, and LET_EFF Calculation

TRF0108-SEP is fabricated in TI's BiCMOS process and the die is packaged as a flip-chip. The decapped unit exposes the silicon substrate directly when packaged in the flip-chip configuration. The units used were background to 50 microns, for proper ion penetration. The effective LET (LET_EFF), depth, and range were determined with the custom RADsim - IONS application (developed at Texas Instruments and based on the latest SRIM2013 [10] models). The application accounts for energy loss in the beam port window setup and the air gap between the DUT and the heavy-ion exit port. An image of the RADsim - IONS is shown in Figure 5-1 and the ions details are presented in Table 5-1. LET_EFF values from RADsim - IONS application were used as calculated reference values while the LET_EFF values shown in Table 5-1 are based on actual beam logs.

Figure 5-1 GUI of RADsim Application Used to Determine Key Ion Parameters