Kinetic Study of Disulfide Molecular Film Deposition for Cu-EMC Adhesion Promotion

This paper presents a study of disulfide thin film onto sputtered Cu substrate. Extrinsic parameter includes solution concentration, deposition time and agitation has been investigated. Ellipsometer was used to measure the molecular film thickness. It has been discovered that agitation which prevents local concentration of disulfide solution, is crucial for success of film deposition. Without agitation, larger thickness variation has been attained (36±22Å comparing with 30±16Å). Furthermore, relatively uniform film (37±10Å for DS-A, 30±8Åfor DS-C) can be realized from low concentration (0.5μM) ethanol in 1 hr. No significant aggregates but few pinholes have been found on disulfide treated surface. An experiment procedure in obtaining uniform thin film from disulfide solution on Cu substrate has been investigated.