Am I eligible to apply for admission in to the Ph.D after completing BCA???

No, you are not eligible to apply for admission in the Ph.D after completing BCA. For admission in the PHD course the applicant should have completed master’s degree with good academic record.

You are eligible for following courses after completing BCA:

Master Of Computer Application (MCA)
Master Degree in Computer Management (MCM)
Master in Management (MIM)/ MSc in Management
Master Of Business Administration
MSc IT
G-CAT Masters
PGDCA (Post Graduation Diploma in Computer Applications )
PGDM (Post Graduate Diploma In Management)
LAW
Mass Communication Courses
M.Com