Western Digital (fremont), Inc.

Lijie Zhao

Ge Yi

Hai Sun

Dujiang Wan

Hongping Yuan

Yunfei Li

Ming Jiang

Wei Zhang

Liubo Hong

Guanghong Luo

Zhong Shi

Hugh Craig Hiner

Winnie Yu

Yanfeng Chen

Lily Yao

Hariharakeshava S Hegde

Rowena Schmidt

A mode converter for use in a Heat-assisted magnetic recording (HAMR) read head to couple or bend light (e.g., from an external laser diode) into a tapered waveguide, and subsequently, to a near field transducer is provided. The mode converter may have an ultra-sharp tip, e.g., less than 200 nm to achieve a desired optical output. Manufacturing such a mode converter involves a two-pattern transform process, where overlay control (using a first edge, such as a right edge, as a reference layer relative to which positioning of a second edge, such as a left edge, is measured) allows for aligning of the right and left edges of a tip portion of the mode converter to ultimately create the ultra-sharp tip.

Method of making an ultra-sharp tip mode converter for a HAMR head

A method for making an interferometric taper waveguide (I-TWG) with high critical dimension uniformity and small line edge roughness for a heat assisted magnetic recording (HAMR) head, wherein the method includes creating an I-TWG film stack with two hard mask layers on top of an I-TWG core layer sandwiched between two cladding layers, defining a photoresist pattern over the I-TWG film stack using deep ultraviolet lithography, transferring the pattern to the first hard mask layer using reactive ion etching (RIE), forming a temporary I-TWG pattern on the second hard mask layer using RIE, transferring the temporary pattern to the I-TWG core using RIE, refilling the cladding layer, and planarizing using chemical mechanical planarization (CMP).

Method to make interferometric taper waveguide for HAMR light delivery

Embodiments of the present invention relate to reducing the size variation on a wafer fabrication. In some embodiments, at least a portion the backfill material over features larger than a threshold size is etched or milled to provide backfill protrusions over those features. The backfill protrusions are configured to reduce the size variation across the fabrication. Embodiments of the invention may be used in fabrication of many types of devices, such as tapered wave guides (TWG), near-field transducers (NFT), MEMS devices, EAMR optical devices, optical structures, bio-optical devices, micro-fluidic devices, and magnetic writers.

Process for CMP with large feature size variation

A method of removing photoresist beneath an overlayer includes estimating a rapid temperature change for a photoresist layer to produce cracking in the overlayer. The temperature chance is estimated so that the cracking of the overlayer is sufficient to allow a liftoff solution to penetrate below the overlayer during a liftoff step. The method further includes baking the photoresist layer and chilling the photoresist layer after baking to produce the rapid temperature change. The method then includes lifting off the photoresist layer using the liftoff solution.

Method for lifting off photoresist beneath an overlayer

A shaper mask for particle flux includes a central portion extending from a body of the shaper mask along a first axis to block at least a first portion of a particle flux through the shaper mask from a first direction. The mask also includes at least one off-axis portion. Each off-axis portions extends from the body of the shaper mask along a respective second axis different from the first axis. Each off-axis portion is shaped to block a respective second portion of the particle flux traveling through the shaper mask from a second direction different from the first direction.

Mask for increased uniformity in ion beam deposition

A method of lifting off photoresist beneath an overlayer includes providing a structure including photoresist and depositing an overlayer impenetrable to a liftoff solution over the photoresist and a field region around the structure. The method also includes forming a mask over the structure and ion milling to remove the overlayer in the field region not covered by the mask. The method then includes lifting off the photoresist using the liftoff solution.

Method and apparatus for lifting off photoresist beneath an overlayer

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Pleasanton, CA, United States of America

Lijie Zhao