For areal densities in the Tb/in{sup}2 range, it will be necessary for the Head-Media Spacing (HMS) to be within 5-7nm [1]. At this level, the disk lubricant thickness is no longer a negligible part of this HMS budget, and it will have an increasingly stronger impact on read/write performance [2]. Recently, dynamic effects of lubricant displacement from shear effect of low flying sliders have been observed [3] and successfully modeled [4]. These dynamic effects are believed responsible for loss of appropriate slider/disk clearance. In this paper, we present an extension to functionalized end-groups. By introducing additional functional hydroxyl groups in the middle of the PFPE chain [5], we will demonstrate that one can achieve reduced clearance, while still achieving overall drive reliability. In a recent publication [6], we have described the synthesis of a Ztetraol multidentate, or ZTMD, whose structure is represented in Figure 1. This molecule is composed of two monomeric Ztetraol (1000 Daltons) units, coupled by a di-epoxy agent, leading to a structure similar to Ztetraol (2000 Daltons), but with four additional hydroxyl groups in the middle of the chain.
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