There are lots of things you can try, but no guarantees offered, because kids this age just do this sometimes. However, you can try any of the following to see if it helps:
1) put a mattress on the floor in your room and tell him if he wakes up he can come sleep on the mattress but he should talk to you or make noise - if he disturbs you you'll have to take him back to his room and leave him (in the dark) until the morning by himself.
2) Keep your bedroom door locked - make sure the hall and rooms are childproof and ignore him when he wakes up. Give him all sorts of toys and ideas to soothe himself with - things he can play with alone in his room till you get up in the morning. Do not under any circumstances respond to his call until it is your wake-up time. In a few nights he'll stop wasting his time trying to get your attention at that time of night.
3) Ask a herbalist for a children's sleepy-tea mixture that can help him sleep a longer and deeper sleep.
4) Make a reward chart for him for staying in his room till you come and get him in the morning.
Good luck!
Sarah Chana