Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Renesas Technology Corp.

Hgst Netherlands, B.v.

Kikuo Kusukawa

Katsuro Watanabe

Norio Suzuki

Yoshio Homma

Shigeo Moriyama

Kenichi Meguro

Toshiaki Yamanaka

Natsuki Yokoyama

Shinichiro Kimura

Akio Nishida

Osamu Tsuchiya

Atsushi Ogishima

Taku Shintani

Masayuki Nagasawa

Tokuo Kure

Masahiro Moniwa

Makoto Ohkura

Hideo Sunami

Masanobu Miyao

Terunori Warabisako

ShinIchiro Kimura

Junichiro Shimizu

Takashi Kobayashi

Hitoshi Kume

Toshiyuki Mine

Kenji Takahashi

Nozomu Matsuzaki

Masataka Kato

Masato Shiimoto

Masukazu Igarashi

Yoshio Kawamura

Nobuo Yoshida

Yo Sato

Toshiaki Nishimoto

Takayoshi Ohtsu

Kazuhiko Hosomi

Takeshi Furusawa

Kouji Kataoka

Masahiko Hatatani

To uniformly determine the positional relationship between a main magnetic pole and a spin torque oscillator while independently optimizing the main magnetic pole and the spin torque oscillator. On a trailing end surface of a main magnetic pole, a step is provided at the boundary between the main magnetic pole and a gap material disposed on both sides thereof, and a spin torque oscillator is formed on the step. The spin torque oscillator is effectively separated into two regions by utilizing the step. Further, a part of the spin torque oscillator is removed so as to disable the unwanted region, thereby realizing a self-alignment type high frequency magnetic field assisted magnetic recording head structure such that the positions of the end portions of the main magnetic pole and the spin torque oscillator are aligned.

High frequency magnetic field assisted magnetic recording head

Provided are a structure of a high frequency magnetic field assisted magnetic recording head in which the positional relationship of a main magnetic pole and a spin torque oscillator in a cross-track direction is accurately determined, and in which variations are not caused in high frequency magnetic field assist characteristics, and a method of manufacturing the structure. The high frequency magnetic field assisted magnetic recording head includes a main magnetic pole, a spin torque oscillator disposed on the main magnetic pole, and an insulating side gap covering a side surface of the main magnetic pole and a side surface of the spin torque oscillator. The main magnetic pole and the spin torque oscillator are formed between both side surfaces of the side gap. Thus, a self-alignment structure of the high frequency magnetic field assisted magnetic recording head is obtained.

High frequency magnetic field assisted magnetic recording head, and method of manufacturing same

According to one embodiment, a high-frequency magnetic field-assisted magnetic recording head includes a main pole adapted for producing a writing magnetic field, a STO positioned above the main pole, a low-resistance layer positioned above the STO, and a current confinement layer positioned between the low-resistance layer and the main pole, wherein the main pole and the low-resistance layer are adapted for acting as poles for writing data to a magnetic medium in response to a flow of current to the STO positioned therebetween to generate a high-frequency magnetic field which overlaps with the writing magnetic field, and wherein the current confinement layer is adapted for controlling a current density and/or a current density distribution of the current flowing to the STO. Other magnetic recording heads and methods of production thereof are also described according to more embodiments.

Microwave-assisted magnetic recording head having a current confinement structure

A magnetoresistive head of a type including a magnetoresistive film arranged between a lower shield layer and an upper shield layer, wherein the lower shield layer has a non-magnetic layer adjacent to it and the lower shield layer and the upper shield layer are formed such that their separation at at least part of a boundary between the lower shield layer and the upper shield layer is larger than their separation in a vicinity of the magnetoresistive film, and an insulating film is arranged between the lower shield layer and the upper shield layer, wherein the lower shield layer and the non-magnetic layer adjacent thereto are formed such that they differ in height and there exists a difference in level at their boundary.

Magnetoresistive head

A magnetic sensor includes a spacer having at least a nonmagnetic metal layer inserted between the upper shield layer and the longitudinal bias layers or between the upper shield layer and the longitudinal bias layers plus the magnetoresistive film, the shortest distance between the longitudinal bias layers and the free layer of the magnetoresistive film is set smaller than the shortest distance between the longitudinal bias layers and the upper shield layer, and this arrangement ensures that the amount of magnetic flux entering the magnetoresistive film from the longitudinal bias layers is larger than that absorbed by the upper shield layer, thus realizing a magnetic sensor whose Barkhausen noise is suppressed.

Magnetic sensor having a free layer containing a single magnetic domain

A high output, magnetoresistive head with a CPP structure is disclosed which reduces or prevents deformation near the air bearing surface of the read element portion layer at the time of air bearing surface processing. In the CPP structure magnetoresistive head, the deformation near the air bearing surface as a result of mechanical polishing during the air bearing surface processing can be reduced by forming deformation prevention layers having a higher shear modulus than the first ferromagnetic layer, and a second ferromagnetic layer between a magnetoresistive film and at least one of a lower shield layer and an upper shield layer.

CPP-type magnetic head with less deformation and a magnetic recording/reproducing system using the same

A magnetoresistive head of CPP structure in which an insulating protective filmcovers at least part of the boundary between the lower shield layerand the non-magnetic filmadjacent thereto so as to reduce the area of the lower shield layer which is exposed on the surface of the substrate when the magnetoresistive film is patterned. This construction minimizes damage that occurs when the magnetoresistive film is patterned and also reduces the fraction defective due to current leakage across the upper and lower shields.

A high output, magnetoresistive head with a CPP structure is disclosed which reduces or prevents deformation near the air bearing surface of the read element portion layer at the time of air bearing surface processing. In the CPP structure magnetoresistive head, the deformation near the air bearing surface as a result of mechanical polishing during the air bearing surface processing can be reduced by forming deformation prevention layers having a higher shear modulus than a first ferromagnetic layer, and a second ferromagnetic layer between a magnetoresistive film and at least one of a lower shield layer and an upper shield layer.

In order to polish an insulating film, a cerium oxide polishing agent (ceria slurry) is used. The ceria slurry is composed of cerium oxide powder containing Na, Ca, Fe, and Cr concentration of which is less than 10 ppm. Fragile inorganic and organic insulating films formed at relatively low temperatures can be polished without degrading the characteristics of the semiconductor element due to Na diffusion.

Polishing agent and polishing method

The CPP structure magnetoresistive head has a structure such that a first lead line is electrically connected to a lead contact portion attached to a lower shield layer the width of which is either equal to or shorter than the maximum length of the lower shield layer in the track direction, or the height of which is either equal to or shorter than the maximum length of the lower shield layer in the stripe height direction. With the structures above, it is possible to prevent that a bump is generated on the upper shield layer by the first lead line, and that a magnetic domain is formed by the bump, which is a cause of noise generation. Further, it is possible to avoid overlapping between the lead line and the upper shield layer.

Magnetic head and a magnetic disk drive

There was a problem that sharpening of a substrate and localized increase in the thickness of a gate oxide film become more remarkable as the thickness of the gate oxide film is increased to degrade the gate withstand voltage at the surface edge of shallow groove isolation structure. In the present invention, a bird's beak is disposed at the surface edge of a shallow isolation structure GROX11 just below gate electrode POLY11 and in contact with the gate insulation film HOX1 to form the gate insulation film HOX1 previously. This can ensure normal gate withstand voltage of the MOS transistor and favorable device isolation withstand voltage and increased integration degree simultaneously.

Semiconductor device having groove isolation structure and gate oxide films with different thickness

In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, then insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved. At the same time, upon chemical mechanical polishing, a silicon substrate can be prevented from being exposed at the central portion of the memory mat portion and the insulating film can be prevented from being left on the silicon nitride film near the outer periphery, thereby making it possible to form elements having uniform electrical characteristics on all active regions of the memory mat portion.

Method of manufacturing semiconductor devices

In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, the insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved. At the same time, upon chemical mechanical polishing, a silicon substrate can be prevented from being exposed at the central portion of the memory mat portion and the insulating film can be prevented from being left on the silicon nitride film near the outer periphery, thereby making it possible to form elements having uniform electrical characteristics on all active regions of the memory mat portion.

Growing community of inventors

Yoshikawa, Japan

Kikuo Kusukawa