The modification of the strength properties of films implanted with Sb+ ions of diazoquinone-novolac photoresist
FP9120 on monocrystalline silicon during long-term storage was investigated by the indentation method.
The dependence of microhardness on the load after implantation was nonmonotonic, due to the presence of elastic
stresses at the photoresist/silicon interface. During long-term storage, their relaxation was observed, which leads
to the disappearance of the non-monotonicity of the microhardness dependences on the load. The crosslinking
of phenol-formaldehyde resin molecules during long-term storage was also noted. This process was stimulated
by the decomposition of diazoquinone during ion implantation. During storage, the implanted photoresistive film
becomes less susceptible to elastoplastic recovery after the load is removed.