If you expect your dog to stay on his own property, be sure he enjoys it there and does not regard it as a prison. Spend time playing with your dog here. Provide a digging pit. Get him a playmate. If you don't want another dog, invite his favorite buddy over to spend the day with him.
Some dogs try to escape because they are frightened.
Observe your dog while he is confined. Sometimes loud construction noises or teasing passersby can make your dog nervous. Again, the solution is in making your dog feel secure, content and relaxed in this area. Spend time with him there and help him build his confidence about being alone. Provide him a secure hiding place in his area in the form of a dog house or crate.