Use of deposition pressure to control residual stress in polycrystalline SiC films

Abstract

Transformer coupled plasma etching of 3C-SiC films using fluorinated chemistry for microelectromechanical systems applications Growth of cubic SiC thin films on Si(001) by high vacuum chemical vapor deposition using 1,3-disilabutane and an investigation of the effect of deposition pressure Residual stress and texture in poly-SiC films grown by low-pressure organometallic chemical-vapor deposition

Control of buckling in large micromembranes using engineered support structures

“…The degree of buckling depends on the length/thickness ratio of a membrane structure: if the ratio is 100 or larger buckling can be significant even for low values of compressive stress (on the order of several tens of MPa). To reduce the effect of the internal stress, stress-reduction techniques based on the optimization of the deposition conditions [8], postdeposition annealing [9], stress-compensation by a deposition of another film [4], and ion implantation [9], [10] have been investigated. These are however material-specific solutions, and therefore cannot be applied in all situations.…”

Diaphragm-based microsystems using thin film silicon carbide

“…The residual stress in as-deposited 3C-SiC films are in the 100MPa to 300MPa range. Poly-SiC films with very low tensile stress can be realized in as-deposited films [3] while amorphous films require only a very short (~8 min) anneal to achieve near zero stress [4]. In terms of electrical properties, single crystalline and polycrystalline films exhibit n-type conductivity at levels suitable for electrostatic actuation while amorphous films are insulating.…”

“…The residual stress in these films is tensile regardless of processing conditions. Production of polycrystalline SiC (poly-SiC) films is performed by low pressure CVD (LPCVD) using a conventional horizontal tube furnace [3]. Dichlorosilane and acetylene are used as precursor gases while doping is performed using ammonia.…”

Micro‐ and nanomechanical structures for silicon carbide MEMS and NEMS

“…One of the principal attributes of the system is the ability to control the residual stress in the resulting films during the deposition process. This can be achieved by proper regulation of either the flow rate of DCS or chamber pressure [78,79]. Residual stresses can be problematic for MEMS if severe, since they can lead to unwanted deformation of suspended structures.…”

“…The sensors utilized lowstress poly-SiC thin film membranes deposited using the process detailed in Ref. [78]. The residual stress in the film was less than 50 MPa.…”