The Initial Sliding Microfriction Properties of Polysilicon Films

Abstract

In the present study, polysilicon films were prepared to investigate the initial sliding microfriction properties using a ball-on-flat micro tribometer when samples were moved against a sapphire ball and a steel ball in ambient environment. The surface topography was measured with AFM. The experimental results indicate that the initial microfriction of polysilicon films fluctuates during a cycle period when sliding against a sapphire ball and this has limited the reliability of present microdevices, but it is stable when sliding against steel ball. This clearly shows the friction force not corresponding to the surface-roughness at low load and electronic contributions to friction should be considered at microfriction. As can be seen from the theory of the contribution to sliding friction from electronic excitations and the experiments above, the polysilicon films can be used in MEMS when sliding against a metal film to get good microfriction properties.

Evolution of Wear Characteristics and Frictional Behavior in MEMS Devices

“…In the past, investigations on tribological properties of polysilicon were conducted either using idealized test structures such as ball-on-flat test device [13,14], AFM [15][16][17][18], and pin-on-disk tester [19] or using MEMS devices [1,[20][21][22][23][24][25][26][27][28][29][30][31]. Flater et al [32] have presented a good review of literature on MEMS friction and wear properties and the some preliminary results on friction and wear behavior of a nanotractor similar to the studies in the current work.…”