The influence of nitrogen and other gases on the magnetic properties of bias-sputtered Co-Cr perpendicular films for computer memory applications

Mapps, D.J.; Mahvan, N.; Akhter, M.A.

doi:10.1109/tmag.1987.1065356

Cited by 16 publications

(6 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recent experiments by Werner et al [9], however, showed that CCr increases notably with VB higher than -100 V. Furthermore, Mapps et al [8] indicated that CCr decreases with increasing N2 partial pressure in a sputtering chamber under the negative bias of -100 V.…”

Section: Introductionmentioning

confidence: 97%

“…Magnetic and crystallographic properties of CoCr sputtered films vary considerably depending on sputtering conditions: substrate temperature Ts [2], impurity gases in a sputtering chamber [3,4] , magnetic field Hs applied normal to substrates [5] and negative substrate~ bias voltage VB [6][7][8] . The hcp caxis orientation normal to the film plane is degraded by impurity gases, especially nitrogen or oxygen [4].…”

Section: Introductionmentioning

confidence: 99%

“…The hcp caxis orientation normal to the film plane is degraded by impurity gases, especially nitrogen or oxygen [4]. On the other hand, the orientation is improved by a magnetic field Hs [5] and by a moderate bias voltage VB [7,8].…”

Section: Introductionmentioning

confidence: 99%

“…Thus, Ms decreases to approach the value of bulk material with negative bias for both the substrate temperatures Ts and for all the magnetic fields Hs. As discussed by several authors, the decrease in Ms arises from the homogenization of Cr distribution, which is induced by VB through several mechanisms: i) the break of Cr-Cr clusters due to the ion-bombardment [6], ii) the suppression of the growth of intercolumnar voids [8], iii) the decrease in the oxygen gettering effect related to the resput tering of oxygen [7,13], and iv) the promotion in the surface diffusion of Cr due to the ion-assist effect [13].…”

mentioning

confidence: 99%

See 3 more Smart Citations

INFLUENCE OF EXTERNAL FIELD APPLIED DURING SPUTTERING ON THE MAGNETIC PROPERTIES OF CoCr FILMS

1989

View full text Add to dashboard Cite

This work investigates the influence of perpendicular magnetic field and negative substrate bias, applied during sputtering, on crystallographic structures and magnetic properties of CoCr films sputtered on polyimide substrates of two different temperatures; 27°C and above 150°C. The sputtering rate at the target increases with magnetic field Hs and/or bias voltage VB, while the deposition rate at the substrate decreases markedly with a bias above -100 Vowing to the resputtering of Co and Cr adhered on the film surface, depending strongly on substrate temperature Ts. The film composition, thereby, changes depending on T s , Hs and VB' The re-sputtering effect notably influences the film morphology and the magnetic proper-ties. The films, having the good orientation of c-axis and thus having the high perpendicular ani sotropy , can be obtained with perpendicular magnetic fields from 35 to 61 Oe.

show abstract

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

INFLUENCE OF EXTERNAL FIELD APPLIED DURING SPUTTERING ON THE MAGNETIC PROPERTIES OF CoCr FILMS

1989

View full text Add to dashboard Cite

show abstract

“…This is probably also for one of the reasons sample 5 which has a better Cl' content x which is smaller than that of either~sample 1 or sample 2,but with 3p or magnetization values are much poorer1ilnthat of other samples. These imply that the crystalline microstructure is an important problem which is related to vacuum pressure Pbg; the occurrence of the fcc phase shows that nitrogen still has influence on the film microstructure, [6]and deteriorates its ~1L.…”

mentioning

confidence: 99%

A STUDY ON THE PREPARATION OF LOW RATE EVAPORATED CoCr PERPENDICULAR MAGNETIZATION FILM

Guo-hong¹,

Qintang²

1989

J. Magn. Soc. Jpn.

View full text Add to dashboard Cite

Serious selective evaporation exists for CoCr films during low rate electron beam evaporation (LREBE), and causes composition discrepancies so that the ratio of x(Crwt%) of the film to X( C1.'I'1t%) of the ingot lies within a ra..'1ge 2.0-3.0. Relations of x with other experiment's factors are given. The reasons for the selective evaporation and composition discrepancies are discussed. On the bases of measured results and micrographs, comparison between the microstructures and magnetic properties of good and poor samples is made. It can be concluded, that many factors influence x and the microstructure of the film and thus also the magnetic properties of the film. Therefore, it is more complicated to control x and the microstructure than in the high rate case. However, the basic theories are similar, and it is useful for studying the basic aspects of CoCr films. In our case, good perpendicular magnetization film (PNF) "\vith I,Is better than 360 (emu/cc) , perpendicular coercivity Hep better than 600(Oe), 4&(50) arround 10(deg) can be obtained. Selective evaporation may exist during deposition, but in papers on high rate electron beam evaporation (HREBE) (1000A~s, beam power 16K'll), where very good CoCr PMFs have been reported[l), we have not seen any mention of this problem. However, if these conditions are not avaible, as in our experiments ,dth LREBE (less than 60Acrs and O.5K1'l) ,and which suffer from other crucial conditions, eg., background pressure pbg of 10E-6 to,rr; no cooling for the substrates ; a distance between ingot and substrate less than 15cm; etc., ca.'} GoCr PNF be acheived? Though the deposition rate compare to that of HREBE is low, it is still usable and is comparable with that of sputtering, but is it still can be used for studying the basic aspects of the CoCr PI·;]'? ;,'hat problems will happen during the deposition?Study of these aspects will have practical significance for the extension of perpendicular magnetic recording applications. EXPERIMENTALThe CoCr PI,IF deposition is made by a home made GlJ;!-450 EB evaporator, with pbg of (2-4)x10E-6 torr, onto glass substrates vTithout cooling. For the deposition rate Rd not to be too low, the distance between the substrates and source had to be ''1i thin 15cm. Halogen lamps were arranged for heating the substrates to desired temperature. The relative substrate temperature Ts which was monitored by a thermocouple is lower than the real substrate temperature.The CoCr percentage "\'las measured by W 5550 :ESl-IA. Film magnetization loops "\'Tere measured by LDJ'9500 ViSN. Torque curves were measured by TP.T-2 'm. Replica micrographs were made by JEM200cx Ta". XDA and Ae(50) .Tere measured by D/max-RB XDA. Film thicknesses t were measured by o(-step200.Through these measurements, it was found that selective evaporation seriously existed during LREBE, and there are many factors ,.;hich can influence the x( Crwt';:) ,deposi tion rate Rd and the microstructure of the films,eg., X(Crwt%) of the ingot and its homogenei ty,the evaporating ti...

show abstract

Microstructure of Longitudinal Media

Lü¹,

Laughlin²

2001

The Physics of Ultra-High-Density Magnetic Recording

View full text Add to dashboard Cite

The influence of nitrogen and other gases on the magnetic properties of bias-sputtered Co-Cr perpendicular films for computer memory applications

Cited by 16 publications

References 3 publications

INFLUENCE OF EXTERNAL FIELD APPLIED DURING SPUTTERING ON THE MAGNETIC PROPERTIES OF CoCr FILMS

INFLUENCE OF EXTERNAL FIELD APPLIED DURING SPUTTERING ON THE MAGNETIC PROPERTIES OF CoCr FILMS

A STUDY ON THE PREPARATION OF LOW RATE EVAPORATED CoCr PERPENDICULAR MAGNETIZATION FILM

Microstructure of Longitudinal Media

Contact Info

Product

Resources

About