تجزیه و تحلیل حساسیت از اسلایدرهای پیکو و فمتو

The flying height sensitivity of pico and femto sliders on air bearing contour design, operating conditions and manufacturing tolerances was studied numerically. A Monte Carlo analysis was performed to evaluate the distribution of flying height, pitch angle and roll angle, assuming the selected independent variables have normal distributions. Two types of pico sliders and one type of femto sliders were modeled and simulated. The results show that flying height is strongly influenced by the contour design of the air bearing slider. The resulting distributions of flying height, pitch angle and roll angle are near Gaussian.

As the magnetic recording density in hard disk drives approaches 100 Gbit/in2, the requirements for hard disk drives become increasingly more stringent. In particular, a small and stable spacing lower than 10 nm must be maintained. For sliders flying at such low spacing, it is important that the flying height is insensitive to the manufacturing tolerances and changes in the operating conditions. This paper studies the effect of manufacturing tolerances on the flying behavior of pico and femto sliders using a finite element based air bearing simulator. Flying height was measured experimentally using a commercially available dynamic flying height tester (DFHT). Good agreement is obtained between simulation results and experimental measurements.

The sensitivity of the flying behavior of three types of sliders was studied as a function of slider design and manufacturing tolerances using the Monte Carlo analysis. The results show that: 1. The resulting distributions of flying height, pitch angle and roll angle are nearly Gaussian. 2. The design of the air bearing geometry is one of the key issues which affects the flying behavior. The design parameters in the high pressure areas are especially important. 3. The relative sensitivity for lower flying height sliders is larger than that for higher flying height sliders. Increased attention must to be exercised to control the manufacturing tolerances when the slider flying height decreases. 4. Flying height, pitch angle and roll angle are nonlinear functions of air bearing step height. 5. Flying height, pitch angle and roll angle are almost linear functions of cavity depth. Sensitivity of slider flying behavior is an important issue which involves many factors. The Monte Carlo analysis provides an effective way to study this problem. Full-size image (7 K)