Although i am also in process of writing my SOP and no expert in this domain, but after reading your essay i have few points to make:
->Specifically mention your current aim i.e M.S or PHD or MS leading to Phd in first paragraph itself
->Adhere to word limit .Your essay is 1500 words long. Admission committee at many universities are very strict about word limit.
->Rather than generically mentioning XX university, search departmental website, shortlist one of two professor working in your area.Provide a brief mention how you connect to them through your work.
->It is good thing that you have mentioned how MEMS fascinates you, it would be good idea to mention what are the areas on which research can be extended.