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APRIL 2025 I SMT007 MAGAZINE 49 tion of BGAs, focusing on key variables such as the type and thickness of the X-ray filter material, the thickness of the circuit board, and the duration of the inspection process. It also examines the impact of X-ray power and voltage settings on the inspection quality. By understanding how these parameters affect the inspection outcomes, the study aims to optimize the X-ray inspection process for better accuracy and reliability. Additionally, the paper outlines strategies for mitigating radiation damage in BGAs, considering three different construction types. ese mitiga- tion techniques are crucial for preserving the integrity and functionality of DRAM during inspection. A test setup was also developed to detect changes in functional performance of the DRAM when exposed to increasing levels of radiation. Experimental Method Radiation measurement was performed using a widely used thermo-luminescent detector (TLD) with an accuracy of ±5% and a minimum reportable dose of 0.01 rad. Figure 2: BGA #1 results: (a) and (b) position of dosimeters on the BGA; (c) and (d) position of dosimeters with respect to the X-ray source; (e) TLD readings in 2D X-ray (MXI) and 3D X-ray (AXI) machines with different filters. Variability Chart for Dosimeter reading (rad) e a c b d TLDs are a useful dosimeter choice, as they are simple to use and good for measuring integrated dose applications. eir princi- ple of operation is to create "color centers" within their crystal structure when ioniz- ing radiation (the X-rays in our case) are absorbed. Subsequent heating of the TLD material releases the stored photons cre- ated by the radiation, as each color center is driven back to its lowest energy state. e results (photons = dose) from the test sample can then be referenced against a calibration table for the TLDs used 4 . e dosimeter was