Common ground for electronic lapping guides

摘要

Embodiments described herein generally relate to connecting Electronic Lapping Guides (ELG) to a lapping controller such that the number of wire bonds from the controller to a row of read heads is minimized. When lapping the air bearing surface of the read heads, the electrical resistances of the ELGs are monitored to adjust the lapping process and set the stripe height for read sensors in the read heads. Once the resistance corresponds to the desired stripe height, the lapping process is stopped. To measure the resistance, each ELG may be electrically coupled to the same substrate—i.e., share the same common ground. The lapping controller applies a voltage potential across the ELGs using a wire bonded to a pad in the respective read head and one or more connections to the grounded substrate. This configuration avoids having to bond two wires onto each read head.

主权项

1. A device, comprising:
a substrate; and a plurality of read heads disposed on the substrate, a first one of the plurality of read heads comprising:
a read sensor configured to detect magnetic orientation changes in a magnetic media,an electronic lapping guide (ELG) configured to indicate, based on a resistance of the ELG, a stripe height of the read sensor, wherein the ELG is electrically coupled to the substrate, anda first bonding pad electrically coupled to the ELG, wherein the first bonding pad, the ELG, and the substrate are part of a current path permitting current to flow through the ELG, wherein each ELG of the plurality of read heads is coupled to two ground pads that are to be separately coupled to a lapping controller.