If you want to continue your education, it will be good if you do B.Tech after diploma. Because if you complete graduation, chances of getting good jobs increase. If you are opting for engineering, then you will directly join 2nd year. There will be jobs after Diploma. But you will be given very lower level positions with very less salary. After completing degree you can get a high salary reputed job. Now it's upto you if you want to continue your education or join a job.

once you complete your diploma,now,you have a practical knowledge on many electrical components.BE is only going to help your enhence  practical knowledge and theoritical knowledge about the subject.so after BE you can search for higher jobs as compared to just doing diploma.