Flexure of hard disk drive
A flexure includes a metal base, a circuit member, and an actuator. The circuit member includes a base insulating layer, a conductor layer, and a cover insulating layer. The conductor layer includes a second pad, and a reference hole, which is an example of a portion to be protected, in a tongue portion. A second end portion of the actuator is fixed to the second pad via an adhesive. The circuit member includes a wall portion. The wall portion is formed between the second pad and the reference hole. A height of the wall portion is greater than a height of the second pad.
1. A flexure of a disk drive comprising:
a metal base including a tongue portion on which a slider is mounted;
an actuator which moves the slider;
a circuit member along the metal base; and
an adhesive which fixes an end portion of the actuator to the tongue portion,
the circuit member comprising:
a base insulating layer formed on the metal base of the tongue portion;
a conductor layer formed on the base insulating layer;
a cover insulating layer covering the conductor layer, and including a first cover layer and a second cover layer formed on the first cover layer;
a pad on which the end portion of the actuator is arranged, and to which the adhesive is applied;
a portion to be protected for which adhesion of the adhesive is to be avoided; and
a wall portion formed between the pad and the portion to be protected, the wall portion comprising at least a part of the second cover layer, and a height of the wall portion from a surface of the metal base being greater than a height of the pad.
2. The flexure of claim 1 , wherein the portion to be protected comprises a reference hole for positioning of the slider.
3. The flexure of claim 1 , wherein the portion to be protected comprises a connecting terminal electrically connected to the slider.
4. The flexure of claim 1 , wherein:
the flexure comprises a reservoir region between the pad and the wall portion; and
the reservoir region comprises a recess in which a height of a part of the base insulating layer formed in the reservoir region is less than a height of a part of the base insulating layer formed in the wall portion.
5. The flexure of claim 1 , wherein the flexure comprises a reservoir region comprising a recess without the base insulating layer being formed between the pad and the wall portion.
6. The flexure of claim 1 , wherein a height of a part of the base insulating layer formed in the pad from the metal base is less than a height of a part of the base insulating layer formed in the wall portion.
7. The flexure of claim 1 , wherein the circuit member further comprises a reservoir region formed between the pad and the wall portion, and a surrounding portion formed at a part facing at least the reservoir region at an outer edge of the tongue portion.
8. The flexure of claim 1 , wherein:
the circuit member includes a two-layer conductive circuit portion;
the two-layer conductive circuit portion comprises a first conductor formed on the base insulating layer, a first cover layer for the two-layer conductive circuit portion covering the first conductor, a second conductor formed on the first cover layer for the two-layer conductive circuit portion, and a second cover layer for the two-layer conductive circuit portion covering the second conductor; and
the wall portion comprises a first cover layer for the wall portion, which is made of polyimide having a same chemical composition as that of the first cover layer of the two-layer conductive circuit portion, and a second cover layer for the wall portion, which is formed on the first cover layer of the wall portion, and is made of polyimide having the same chemical composition as that of the second cover layer of the two-layer conductive circuit portion.