Heat treatment of NFT and surrounding material
The present disclosure relates to pretreating a magnetic recording head. For a HAMR head, a NFT is present. Current can be applied to the NFT to condition the NFT. The current is applied in one of three ways: slowly ramping up the current from a starting level below a level capable of writing data to the optical laser current over a predetermined period of time, applying the current at a fixed value below the optical laser current for the predetermined period of time, or slowly ramping up the current from a starting level below a level capable of writing data to the optical laser current over the predetermined period of time while also intermittently removing the current. By conditioning the NFT in such a manner, the HAMR head can avoid thermal shock and thermal fatigue and thus increase the lifetime of the magnetic media drive.
1. A magnetic media drive, comprising:
a magnetic recording head;
a magnetic media; and
a control unit coupled to the magnetic recording head and the magnetic media, wherein the control unit is configured to:
apply laser current to the magnetic recording head, wherein the laser current is applied at a first level that is below a laser current level capable of writing data to the magnetic media, wherein the first level is applied for a first period of time;
remove the laser current applied at the first level;
apply laser current to the magnetic recording head at a second level that is greater than the first level, wherein the second level is below the laser current level capable of writing data to the magnetic media, wherein the second level is applied for a second period of time;
remove the laser current applied at the second level; and
determine whether a total predetermined period of time has passed.
2. A magnetic media drive, comprising:
a magnetic recording head;
a magnetic media; and
a control unit coupled to the magnetic recording head and the magnetic media, wherein the control unit is configured to:
apply laser current to the magnetic recording head, wherein the laser current is applied at a first level that is below a laser current level capable of writing data to the magnetic media, wherein the first level is applied for a first period of time:
remove the laser current applied at the first level;
apply laser current to the magnetic recording head at a second level that is greater than the first level, wherein the second level is below the laser current level capable of writing data to the magnetic media, wherein the second level is applied for a second period of time; and
remove the laser current applied at the second level, wherein the removing the laser current applied at the first level lasts for a third period of time, wherein removing the laser current applied at the second level lasts for a fourth period of time, and wherein the third period of time is equal to the fourth period of time.
3. The magnetic media drive of claim 2 , wherein the first period of time is equal to the second period of time, and wherein the first period of time is not equal to the third period of time.
4. The magnetic media drive of claim 1 , wherein the control unit is further configured to:
apply laser current to the magnetic recording head at a third level that is greater than the second level, wherein the third level is below the laser current level capable of writing data to the magnetic media, wherein the third level is applied for a third period of time; and
remove the laser current applied at the third level.
5. The magnetic media drive of claim 4 , wherein a difference between the first level and the second level is equal to a difference between the second level and the third level.
6. The magnetic media drive of claim 1 , wherein the control unit is further configured to determine whether LOPTI has been reached.
7. The magnetic media drive of claim 6 , wherein the control unit is further configured to increase laser current upon determining that LOPTI has not been reached.
8. The magnetic media drive of claim 6 , wherein the control unit is further configured to indicate the magnetic media drive is ready for operation upon reaching LOPTI.
9. The magnetic media drive of claim 1 , wherein the control unit is further configured to increase laser current upon determining that the total predetermined period of time has not passed.
10. The magnetic media drive of claim 1 , wherein the control unit is further configured to indicate the magnetic media drive is ready for operation upon determining the total predetermined period of time has passed.
11. The magnetic media drive of claim 1 , wherein the magnetic recording head comprises a near-field transducer (NFT).
12. A method of treating a magnetic recording head during manufacturing, comprising:
prior to a read/write operation of the magnetic recording head, applying a current to the magnetic recording head for a first period of time, wherein the current is below a current level capable of writing data to a magnetic recording media;
determining one of the following:
whether the current level capable of writing data to the magnetic recording media been reached; or
whether a predetermined period of time passed;
performing one of the following prior to a read/write operation of the magnetic recording head:
continuing to apply the current at the current level capable of writing data to the magnetic recording media for a second period of time; or
removing application of the current for a third period of time; or
increasing the current to a new current level that is below the current level capable of writing data to the magnetic recording media; and
determining the magnetic recording head is ready for read/write operations.
13. The method of claim 12 , wherein the current level capable of writing data to the magnetic recording media is reached at the predetermined period of time.
14. The method of claim 12 , wherein the current level capable of writing data to the magnetic recording media is reached after increasing the current level.
15. The method of claim 12 , wherein the current applied is constant.
16. The method of claim 12 , wherein the current is increased upon determining that LOPTI has not been reached.
17. The method of claim 12 , wherein the current is increased upon determining that the predetermined period of time has not passed.
18. The method of claim 12 , wherein current is maintained for the predetermined period of time.
19. The method of claim 12 , wherein the current is applied to a near-field transducer (NFT) of the magnetic recording head.