The US Electron-Ion Collider (EIC) is a future facility to be built at the Brookhaven National Laboratory (BNL) to study the collisions of polarized electrons with polarized protons and ions. It will provide the answers to fundamental questions on quark and gluon interactions such as: how colored partons and colorless jets travel in the nuclear medium, the properties of the state of matter in high gluon density (low-x) regime, distribution of quarks, gluons, and their spin inside a nucleon. EIC is expected to run at the luminosity of 1032-1034 cm-2 sec-1 and center-of-mass energy 20-140 GeV [1]. ATHENA (A Totally Hermetic Electron Nucleus Apparatus) is one of the detector designs provided as the response to the call for the proposal issued by the EIC Project in 2021. It consists of a tracking system with wide pseudorapidity coverage (|η|<3.5), high granularity (pixel size of inner layers ~10 μm), and low material budget (0.05% of X0 per layer) for the innermost silicon layers to achieve good tracking and vertexing performances.