This technique is intended to improve the mobility of the carrier using strained Si. We evaluated the strain introduced in a Si substrate by a patterned SiN film that was made by slot plane antenna (SPA) on Si substrate using UV-Raman spectroscopy. We confirmed that the tensile/compressive strain was induced under a SiN film with compressive/tensile inner stress. The density of the film was evaluated using X-ray reflectometry and was proportional to the inner stress of the film. Therefore, the induced strain can be controlled by changing SiN chemical vapor deposition conditions. The density can be controlled by N/Si ratio and H concentration. The SiN inner stress can be controlled by the density. And, the SiN inner stress can control the induced strain. This is the mechanism of strain introduction. Furthermore, annealing increased the film density and changed the induced strain.