Nano-porous　silicon　oxide　film　with　low　dielectric　constant,　compositing　with　aluminum　can　greatly　reduce　the　resistance　loss,　it　is　the　most　promising　of　the　new　generation　of　low　dielectric　material.　In　nano-electronics,　the　mechanical　properties　of　the　low　dielectric　film　can　be　controlled　by　its　porosity　and　pore　size.　The　elastic　modulus　is　a　required　parameter　in　device　designs.　However,　the　traditional　methods　can　not　characterize　the　elastic　modulus　at　the　nano-scale.　Herein,　using　plasma　enhanced　chemical　vapor　deposition　(PECVD)　method,　hexamethyldisiloxane　(HMDSO)　is　as　monomer　and　oxygen　as　a　reaction　gas,　meanwhile　a　small　amount　of　organic　material　is　added,　the　silicon　oxide　film　is　deposited　on　the　glass　substrate　surface　with　glow　discharge　plasma,　then　the　film　is　heat-treated　at　a　high　temperature,　so　organic　components　such　hydrogen　bonds　are　removed　and　the　pores　are　formed　(hereafter　refer　to　nano-porous　silicon　oxide　film)　to　reduce　the　dielectric　constant.　The　results　show　that　the　refractive　index　of　the　silicon　oxide　film　is　reduced　with　heat　treatment,　wherein　when　the　discharge　power　is　100　W,　ratio　of　oxygen　to　monomer　is　1:4,　the　discharge　time　is　10min,　the　refractive　index　of　the　film　is　minimized　after　the　heat　treatment,　the　dielectric　constant　is　1.885.　At　the　same　time,　using　ultrasonic　atomic　force　microscopy　system　(UAFM)　the　elastic　modulus　of　the　nano-porous　silicon　oxide　film　is　tested　with　non-destructive.　Silicon　oxide　nano-film　as　a　reference　sample,　elastic　properties　silicon　oxide　films　with　heat-treated　is　detected　experimentally.　Indentation　modulus　of　silicon　oxide　nano-film　after　heat　treatment　is　35.24　GPa.　Comparing　to　the　silicon　oxide　nano-film　with　78.8　GPa　indentation　modulus,　it　reduces　42.94　GPa　for　nano-porous　silicon　oxide　film.　©　2018　Journal　of　Mechanical　Engineering.