Physics; Materials testing; Ultrasonic resonance test method; MICROSTRUCTURE OF MOLECULAR SYSTEMS (PHYSICS); ULTRASCHALLMESSTECHNIK; Ultrasonic measurements; EIGENSCHAFTEN DÜNNER SCHICHTEN (PHYSIK VON MOLEKULARSYSTEMEN); ULTRASONIC MEASUREMENTS; Numerical simulation and mathematical modeling; Microstructure of molecular systems; NUMERISCHE SIMULATION UND MATHEMATISCHE MODELLRECHNUNG; NUMERICAL SIMULATION AND MATHEMATICAL MODELING; ULTRASCHALLRESONANZVERFAHREN (MATERIALPRÜFUNG); MIKROSTRUKTUR VON MOLEKULARSYSTEMEN (PHYSIK); ULTRASONIC RESONANCE TEST METHOD (MATERIALS TESTING); Physics of molecular systems; PROPERTIES OF THIN LAYERS (PHYSICS OF MOLECULAR SYSTEMS); Properties of thin layers