I would like to focus that it depends upon your interest. According to me ECE is better, because it is a core branch and have very good placement statistics in almost every college. Whereas, mechatronics is sub branch of mechanical engineering and has not been run by many institutes
So if you want to pursue B.Tech in India , then you should take ECE as it is offers by good colleges so there are high chances you met with a very good package.
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile