Unfortunately, the fact is your dog is able (and knows she is able) to jump the fence. Were you out there with her when she jumped? I wouldn't leave her outside unsupervised, if she can jump into the neighbor's yard, she can jump out too and possibly get lost, or worse.
How tall is the fence now? I'm just assuming its 4' chain link right now.
Maybe you can plant some large shrubs in front of the fence so she has more distance to cover... although that might be more expensive than making the fence higher. To make it taller, maybe you can add something on top of your current fence instead of totally replacing it. Something like trellis?
Good luck!