Hello Shrikant,
After BCA, it is better to do MCA ,as this is the course related to your graduation study course.

M.Tech is a better choice for a B.Tech student. Now the things you have gone through in BCA, are going to be studies in an elaborated manner.

So ,it will be much helpful for you to pursue the MCA after BCA, as far as i think

ELIGIBILITY CRITERIA:

• He/ she needs to have passed bachelor degree course in computer applications (BCA) or any related fields.
• In case of merit based admission process, the candidate need to have secured a minimum aggregate marks as per the institute’s requirement in last qualifying examination.
• In case of entrance exam, the candidate is must to clear the entrance exam and subsequent rounds such as GD and PI to secure admission in MCA course