Write head designs with refill materials on a back edge of an assist device for improved write head reliability and performance

A head gimbal assembly comprising:

• a recording head including a slider and a device connected to the slider, the device including:
• a main pole;
• a trailing shield;
• an assist device disposed between the main pole and the trailing shield;
• a first metal layer disposed at a first side to a back edge of the assist device and a side of the main pole;
• an insulator layer disposed adjacent to a second side of the first metal layer;
• and
• a metal material disposed adjacent to the insulator layer and the trailing shield;
• a load beam connected to the recording head;
• and
• a suspension connected to the load beam and configured to support the recording head.

A method for manufacturing a write head, the method comprising:

• forming a main pole;
• disposing an assist device in a gap formed between the main pole and the trailing shield;
• disposing an insulator layer adjacent to a back end of the assist device and a side of the main pole;
• disposing a metal material adjacent to the insulator layer and the trailing shield;
• and
• disposing a trailing shield adjacent to the main pole.