Film stress management for MEMS through selective relaxation
View Patent ↗An apparatus comprising a microelectromechanical system. The microelectromechanical system includes a crystalline structural element having dislocations therein. For at least about 60 percent of adjacent pairs of the dislocations, direction vectors of the dislocations form acute angles of less than about 45 degrees.
1. A device, comprising:
A microelectromechanical system including:
A crystalline structural layer having dislocations therein, wherein for at least about 60 percent of adjacent pairs of said dislocations, direction vectors of said adjacent pairs form acute angles of less than about 45 degrees, said crystalline structural layer having a suspended portion whose major or minor surface is bent.
2. The device of claim 1 , wherein a density of said adjacent dislocations is at least two times higher in one or more defect sub-regions than in remaining regions of said crystalline structural layer.
3. The device of claim 1 , wherein at least about 80 percent of said adjacent pairs of said dislocations form said acute angles of less than about 20 degrees.
4. The device of claim 1 , wherein said crystalline structural layer includes two adjacent crystal layers, wherein said layers have bulk lattice constants that differ by more than about 0.1 percent and said dislocations include misfit dislocations located at an interface between said adjacent crystal layers.
5. The device of claim 1 , wherein said crystalline structural layer consists essentially of a single crystal layer and said dislocations include edge dislocations located in said single crystal layer.
6. The device of claim 1 , wherein said crystalline structural element has at least one bend therein.
7. The device of claim 1 , wherein a bend axis of said crystalline structural layer is substantially parallel to an average direction of said dislocations.
8. The device of claim 1 , wherein said crystalline structural layer has a substantially planar major side and a curved minor side.
9. The device of claim 1 , wherein said crystalline structural layer includes implanted atoms that are located at nucleation sites of said dislocations.
10. The device of claim 1 , wherein said microelectromechanical system forms a portion of an optoelectronic component.