Development And Applications Of Graphenebased Microfilms In The Lubrication Of High Sliding Silicon Devices

Microsystems technology is sophisticatedly integrating miniaturized components such as sensors,actuators,and signal processing over a small area using microfabrication techniques,and offers new functionalities,and performance advantages over conventional devices.Silicon is the mostly used substrate material for the manufacturing of sliding silicon-based devices.A major challenge in the development of silicon devices with contacting and sliding surfaces is the provision of effective lubrication for sliding parts.This is greatly limiting the development,and exploitation of silicon devices.This study aimed to design and investigate the graphene-based microfilms in the lubrication of sliding silicon-based devices.Graphene-based microfilms were developed by chemical vapour deposition(CVD)and were transferred on the silicon specimen using a polymethyl methacrylate(PMMA)spraying method.By calculating the different factors of film deposition like diffusion parameters,surface roughness the theoretical basis for the development of graphene microfilms in the lubrication of sliding silicon devices was established.Moreover,according to the working conditions,and principal of pin-on-disk reciprocating UMT-2 tribometer,a pin-on-disk friction-pair was designed in such a way that it mimics the sliding silicon devices.A silicon-based stationary pin of 3 mm was fixed on the upper specimen holder,and graphene-films deposited disk of 10 mm was fastened on the reciprocating lower specimen holder,and processing quality of friction-pair was characterized by scanning electron microscopy(SEM),Raman spectrometer and Atomic force microscope(AFM).Different tribological tests and surface morphology analysis were carried out to investigate the tribological performance of graphene-based microfilms using a commercially available UMT-2 tribometer,and SEM.Results show that the friction coefficient of the graphene films is associated with the number of films and roughness in the films.That's why sample with three graphene films had shown the lowest friction coefficient,and wear and sample without graphene films had shown the highest friction coefficient.Conversely,the wear is dependent on the roughness in the films and the number of films on the sample.Due to this,the sample with one graphene film was severely damaged than samples with two and three number of films.Therefore,it is concluded that these excellent tribological properties of graphene microfilms can significantly prolong the life of silicon devices,and are expected to be suitable solid lubricants for sliding silicon-based devices.This paper contains 40 figures,8 tables,and 108 references.