Laparoscopic tool shafts and devices and methods for enhancing their rigidity in general or in specific directions are provided. In various embodiments, provided are MALDI ion sources configured to irradiate a sample on a sample surface with a pulse of laser energy at angle within 10 degrees or less of the surface normal, and a first ion optics system configured to extract sample ions in a direction within 5 degrees or less of the surface normal. A gate insulating layer may be on the capping layer to cover the region of the channel layer, and a gate may be on the gate insulating layer.