{{tag>collection_az vendor_unknown type_crypto type_crypto/smartcard year_unknown tech_unknown foundry_unknown}}

SIM card from an old AT&T cell phone. No vendor logo, die copyright, or other identifying markings whatsoever.

====== Package ======

{{:azonenberg:unknown:dscf5046_cropped.jpg?500|}} {{:azonenberg:unknown:dscf5047_cropped.jpg?500|}}

====== Die carrier ======

{{:azonenberg:unknown:dscf5050_cropped.jpg?500|}} {{:azonenberg:unknown:dscf5051_cropped.jpg?500|}}

====== Die ======

Size is approximately 2000 x 1340 μm (2.68 mm<sup>2</sup>).

===== Top layer =====

{{:azonenberg:unknown:att_sim_bf_neo10x_4k.jpg?800|}}

The mesh appears pretty weak: one serpentine line zigzagging back and forth with ~850 nm pitch (probably 400-500 nm lines, consistent with the ~180 nm technology node). Since it appears there's only one net there would be no penalty for shorting adjacent lines together, or for cutting out a sizeable area and bypassing it.

{{:azonenberg:unknown:att_sim_11_bf_neo40x_annotated.jpg?600|}}

===== Next layer down =====

HF etched until mesh removal, but not imaged yet.