The scarcity of samples in hardware reverse engineering demands a high-success-rate sample preparation process to prevent irreversible information loss or the introduction of analytical artifacts. As semiconductor packaging shifts toward System-in-Package (SiP), chiplet, 2.5D/3D, and high-density interconnect architectures, traditional acid decapsulation and vacuum-based plasma etching are reaching their limits. These methods often risk metallization damage or die over-etching, lacking the precision required to selectively remove Epoxy Mold Compound (EMC) for exposing localized failure sites or hidden security features in advanced modules. In this context, atmospheric Microwave-Induced Plasma (MIP) addresses these challenges by providing localized and highly selective removal of EMC, underfill, and overmold materials while preserving underlying dies, interconnect structures, and metallization. Because the MIP process relies on neutral radical species rather than ion bombardment, the electrical functionality of the device remains intact. These features enable access to physically protected and security-sensitive locations without compromising operational or structural integrity.

Several case studies and repackaging workflows are presented to illustrate how MIP unlocks new possibilities for hardware reverse engineering and security assessment. Demonstrated applications include: (1) uncovering critical interconnects in 2.5D heterogeneous integration SiP architectures for physical security assessment, (2) accessing embedded EEPROM dies within a SiP on a PCB for electrical probing, (3) extracting data from damaged devices via package-level repair, and (4) enabling Known Good Die (KGD) repackaging workflows for dynamic analysis.