Papers by Keyword: Mechanical Strain

Abstract: We present a detailed study of the behavior of the photoluminescence (PL) of the TS color center in 4H-SiC under controlled mechanical strain. We have investigated the TS1 line under varying strain, including its reaction to compression and tension. We use emission polarization measurements to gain access to the orientation of the underlying defects. We put our results in context with previous findings and find good agreement, corroborating the proposed microscopic model.

Abstract: This paper reports the successful substrate transfer based on standard IC processing to an alternative substrate e.g. plastic. The device on ultra-thin Si substrate using grinding backside Si and thermo-compression bonding process is proposed. Acceptable electrical performances are achieved means that the substrate transfer process is controlled well. The DC characteristics of nMOSFETs as a function of orientations and device sizes under mechanical strain are also reported. Good performance and reliability of nMOSFETs under mechanical strain is obtained. The results suggest the feasibility of substrate transfer in achieving well-performance nMOSFETs for 3D integration or SiP technologies.

Abstract: A temperature-compensating fiber Bragg grating(FBG) sensor having two different FBGs in one fiber line was applied to the real time measurement of mechanical normal strain in structures. Measurement of mechanical strains of the aluminum beam surface by the double FBG sensor was performed under various thermal conditions, which was compared with results of electrical resistance strain gage. The FBG sensor fabricated in this study could detect accurately values of mechanical strains without containing any thermal strain component.

Abstract: The purpose of the present study was to observe the response and changes of cranial suture to the distraction forces in growing goats and to examine the expression patterns of TGF-β and BMP during suture distraction.Twenty growing goats were divided into three groups: control (n=4), experimental (n=12), and sham (n=4). A pure titanium distractor was placed in the coronal suture in both the sham and experimental groups. After healing, the distractor was activated for distraction of the coronal suture at a rate of 0.5 mm/day for 8 days in the experimental group. Three animals were killed respectively, at 0，2，4 and 8 weeks after completion of suture distraction. No force was applied in the sham group. X- Ray examination was taken and the coronal suture samples were harvested and processed for histological analysis and scanning electron microscopic analysis and immunohistochemistry of TGF-β and BMP. The coronal sutures of experimental group were separated successfully. Signs of intramembranous bone formation and remodeling were found in the distracted suture，and the sutural structure almost return to its normal state at 8 weeks after end of distraction. At 0 and 2 weeks after completion of suture distraction, the collagen fiber bundles were strengthened and aligned in the direction of the distracted forces. Strong expression of BMP and TGF-β were detected in the fibroblast-like cells and the active osteoblasts. At 4 weeks after suture distraction, signs of intramembranous ossification were found in the edge areas of the distracted suture, and the positive staining of BMP and TGF-β was still noted in the osteoblasts around the newly formed bone trabeculae. This study suggests that cranial suture expansion can be achieved in growing animal by distraction osteogenesis. Mechanical strain resulted from distractor can induce the adaptive remodeling in the cranial suture of growing goats. It also suggests BMP and TGF-β may play very important roles in the process of bone formation and remodeling during suture distraction osteogenesis.

Abstract: We have designed a new four-point bending system by combination of integrate circuit and beam-deflection theory, and conducted a series of experiments concerning cell morphology and proliferation. The system was proved to be able to supply the cultured anchorage-dependent cells with cyclic uniaxial stretching strain and compressive stress easily, precisely and effectively.