ETRI inurnal, volume 16, number 1, April 1994
`
`45
`
`A Study on Modified Silicon Surface after
`
`CH F3/C2F6 Reactive Ion Etching
`
`Hyung-Ho Park, Kwang-Ho Kwon, Sang-Ewan Lee, Byung-Hwa Koak, Sahn Nahm,
`
`Hee-Tae Lee, Kyoung-Ik Cho, Oh-Joon Kwon and Young-II Kang
`
`CONTENTS
`
`ABSTRACT
`
`"
`ll
`
`'NTRODUCT‘ON
`EXPERIMENTAL
`
`III. RESULTS AND DISCUSSION
`
`lV- CONCLUSIONS
`
`The effects of reactive ion etching (RIE)
`of sro2 layer in CHF3 / czrfi on the un—
`deriying Si surface have been StUdlEd by X-
`ray photoelectron spectroscopy (XPS), sec-
`0ndary ion mass spectrometer, Rutherford
`backscattering spectroscopy, and high res-
`olutiOn tranSmissiOn electron microscopy.
`We found that two distinguishable modi—
`fied layers are formed by RlE :
`(i) a uni—
`form residue surface layer of 4 nm thick-
`ness composed entirely of carbon, fluo-
`rine, oxygen, and hydrogen with 9 different
`kinds of chemical bonds and (ii) a contam-
`inated silic0n layer of about 50 nm thick-
`ness with carbOn and fluorine atoms with—
`
`out any observable crystalline defects. To
`search the removal condition of the sil—
`
`icon surface residue, we monitored the
`changes of surface compositions for the
`etched silicon after various post treatments
`as rapid thermal anneal, Oz, NF3, SF5, and
`Cl; plasma treatments. XPS analysis re-
`vealed that NF3 treatment is most effec-
`tive. With 10 seconds exposure to NF3
`plasma, the fluorocarbon residue film de-
`composes. The remained fluorine com-
`pletely disappears after the following wet
`cleaning.
`
`IP Bridge Exhibit 2222
`IP Bridge Exhibit 2222
`TSMC v. Godo Kaisha IP Bridge 1
`TSMC v. G0d0 Kaisha IP Bridge 1
`IPR2017-01843
`IPR2017-01843
`
`

`

`46
`
`Hyung-Ho Park, et al.
`
`ETRI journal, volume 16, number 1, April 1994
`
`I.
`
`INTRODUCTION
`
`II. EXPERIMENTAL
`
`Reactive ion etching (RIB) of SiOz on Si
`
`A layer of 600 nm thick oxide was de-
`
`in a fluomcarbon plasma is a standard process
`
`posited on a chemically cleaned 0.85-1.15
`
`in the production of very large scale integrated
`
`ohm-cm, B doped (100) silicon wafer by low
`
`devices. But it can cause damage and contam-
`
`pressure chemical vapor deposition method.
`
`ination effects in exposed materials [1,2].
`
`RIE process were performed in QUAD 484
`
`In fact, plaSma species can be trapped in the
`
`silicon matrix, and residue layers can be made
`
`Dryteck system using a CHF3 / C2F5 gas mix-
`ture. RF power density was 1.203 W/cmz. The
`
`up of reactant species and reaction products.
`
`gas flow was 100 sccrn and the chamber pres-
`
`Various fluorocarbon plasma treatments
`
`sure was 700 mTorr.
`
`In this experiment, 80
`
`and their interaction with the Si or SiOz sur-
`
`seconds of silicon overetching was performed
`
`faces have been analyzed in recent years [3-5].
`
`after reaching the Si02/Si interface. The etch
`
`For removal of silicon surface residue re-
`
`end point was detected by laser interferome-
`
`sulting from the RIE, oxygen plasma ashing
`
`or downstream soft etching treatments have
`
`try. 02 plasma treatment was effectuated with
`PR stripper of Barrel type. NF3, SF5, and C12
`
`been studied [6,7]. Although oxidizing pro-
`
`plasma treatments were carried out after RIE
`
`cess is used for removing the surface residue
`
`using Applied Materials Precision 5000 sys-
`
`at present, this approach presents a problem of
`
`tem without applying a magnetic field. The
`
`consuming the silicon substrate due to oxida-
`
`gas pressure was 100 mTorr and RF power was
`
`tion and changing in the physical dimension
`
`150 watts. Post etch treated samples were im-
`
`for a cell.
`
`mersed in H2804 / H202 (4/ 1) and in 1 / 20
`
`In this study, a modified silicon surface af-
`
`buffered HF successively to investigate the wet
`
`ter RIE in CHF3 / C2F5 plasma has been inter-
`
`cleaning effect. Rapid thermal anneal (RTA)
`
`preted in detail using X-ray photoelectron Spec-
`
`treatments were carried out at nitrogen atmo—
`
`troscopy (XPS), secondary ion mass spectrom-
`
`Sphere for 1 minute. Prior to RTA treatments,
`
`eter (SIMS), Rutherford backseattering spec-
`
`the wafers were given a wet cleaning.
`
`troscopy (RBS), and high resolution transmis—
`
`The XPS experiments were performed on a
`
`sion electron microscopy (HRTEM).
`
`V. G. Scientific ESCALAB 200R spectrometer
`
`And as post etch treatments to remove sili-
`
`using Mg kor (1253.6 eV) operating at 300 W
`
`con surface residue resulting from the RIB, the
`
`radiation. Narrow scan Spectra of all regions of
`
`effects of 02, NF3, SF6, and C12 plasma treat-
`
`interest were recorded with 20 eV pass energy
`
`ments have been studied. Rapid thermal anneal
`
`in order to quantify the surface composition
`
`treatment has been also carried out.
`
`and identify the elemental bonding states. The
`
`

`

`klZ
`
`Counts
`
`96
`
`104
`102
`100
`98
`Binding Energy/9V
`
`105
`
`
`
`
`
`230 282 284 236 233 290 292 294 296
`Binding Energy/eV
`
`(a)
`
`(b)
`
`
`
`684
`
`692
`690
`688-
`686
`Binding Energy/av
`
`694
`
`(d)
`
`8000
`
`6000
`
`2000 H—L _|—l—I_
`
`M a
`
`:3
`
`63 4000
`
`528
`
`536
`534
`532
`530
`Binding EnerEY/ev
`
`538
`
`(C)
`
`E-‘f 9;. 2. Deconvolutions of narrow scan spectra with pass energy of 20 (N for reactive ion etched sample; (a) Si 2p, (b) C
`
`Is, (c) 0 Is, and (d) F 15.
`
`SIMS results were obtained with CAMECA
`
`[MS-4F by monitoring the negatively charged
`
`secondary ions using oxygen ions bombard-
`
`ment. The oxygen primary beam current was
`
`30'nA with net bombarding energy of 8 keV.
`
`For ion channeling experiments, He+ ions of
`
`The XPS analysis shows that the residue
`
`film due to exposure of silicon surface to CHF3
`
`/ C2F6 reactive ion plasma consists mainly of
`
`carbon and fluorine.
`
`1 MeV were used and backseattered ions were
`
`Fig. 1 represents narrow scan spectra of
`
`collected at the detection angle of 110 degrees
`
`Si, C, O, and F. No considerable peak shape
`
`with NBC 3SDH. The cross-sectional HRTEM
`
`change due to X-ray irradiation has been ob-
`
`analysis was carried out with Philips CM20T/
`
`STEM and operating voltage was 200 kV.
`
`served during the measurement. Their peak
`
`attributions, binding energy, full width at half
`
`maximum (FWHM), and percent of total area
`
`(contributiOns of several bonds to the integrated
`
`peak) are listed in Table 1. The Si 2p spectrum
`
`

`

`Hi
`
`,‘ri‘flvi'iiii.
`
`'M‘Hil'fl")
`
`.(1. fill?” HI? I..
`
`'_'"..'
`
`‘
`
`'-.
`
`to Si with a binding energy of 532.6 eV. The
`
`0 Is binding energy of 534.8 eV seems to be
`
`resulted from the bond with a high electrOneg-
`
`ative element as fluorine. In the F Is spectrum,
`
`we also find the presence of the bond with oxy-
`
`gen at 692.1 eV.
`
`10_’
`
`10‘
`
`105 I
`
`V. ’
`
`10‘.
`
`10‘
`
`103
`
`
`
`SecondaryIonCounts
`
`
`
`Table l. Decompositions of the Si 2p, C is, O ls, and F
`ls core level distributions.
`
`
`
`
`
`
`0
`
`200
`
`400
`
`600
`
`800
`
`1000
`
`1200
`
`Depth ( angstrom)
`
`"5,12. 2. SIMS depth profile after reactive ion etching.
`
`Fig. 2 represents the depth profile of vari-
`
`ous elements measured by SIMS. It is shown
`
`can be resolved into Si-Si, Si—C, and Si—O/F.
`
`that the impurities in the ~50 nm thick sili-
`
`The binding energy of Si as 102.8 eV for Si-O
`
`con substrate mainly consists of carbon and
`
`bond means that incomplete oxidation of sili—
`
`fluorine. RBS / channeling spectra are given
`
`con occurs [8] because 103.4 eV binding en-
`
`in Fig. 3 for reactive ion etched silicou and
`
`ergy is observed for normal Si-O bond in Si02 .
`
`control samples. The control sample has been
`
`And the Si—O boud contains a small quantity of
`
`cleaned with a buffered HF solution before
`
`Si-F bond because a few fluorine is revealed
`
`RBS measurement. At 183, 236, and 273 chan-
`
`to bind to silicon in F ls spectrum. The C ls
`
`nels, peaks due to C, O, and F contaminants
`
`spectrum can be resolved into 6 chemical com-
`
`are shown for the reactive ion etched silicon.
`
`ponents which can be attributed to C—Si, C-C
`
`Increase in the silicon surface peak intensity
`
`or H, C-CF,r (x E 3), GE, C-Fz, and C—F3,
`
`for the reactive i0n etched sample may result
`
`TCSPCClively. The majority of O atoms bind
`
`from the existence of the fluorocarbon residue
`
`

`

`ETRI lournal, volume 16, number 1, April 1994
`
`Hvung—Ho Park, et al.
`
`49
`
`
`
`350
`
`150
`
`950
`
`Fig. 3,
`
`Ion channeling spectra of central sample and
`
`reactive ion etched sample.
`
`film on the reactive ion etched silicon surface
`
`or frorn silicon crystalline defects which can be
`
`produced by carbon and fluorine contaminants.
`
`The position of the silicon surface peak for the
`
`reactive ion etched sample has been shifted by
`about 2.4 keV relative to the control sample due
`to the energy loss of He+ beain during the pas-
`
`sage through the residue layer. To check any
`
`
`
`Fig. 4, Cross-sectional HRTEM image of reactive ion
`etched silicon.
`
`possible crystalline damage in the silicon sub-
`
`strate containing the impurities, cross-sectional
`
`HRTEM irriages have been taken for the re-
`
`active ion etched silicon. About 40 nm thick
`
`gold is deposited to distinguish the fluorocar-
`
`bon residue layer from epoxy which is used for
`
`cross-sectional TEM specimen preparation.
`
`Fig. 4 represents the image. The residue
`
`layer is continuous and uniform. The thickness
`
`of the residue layer is measured as ~ 4 nm using
`
`a spacing of Si (111) planes of 0.313 nm as an
`
`internal magnification standard. The interface
`
`between the residue layer and silicon substrate
`
`is sharply defined and smooth. In the substrate
`
`silicon lattice image, we can find neither point
`
`defect cluster nor distinct planar defect. From
`
`these results,
`
`the relatively high intensity of
`
`silicon Surface peak for the reactive ion etched
`
`sample compared to the control sample in ion
`
`channeling spectra (Fig. 3) can be attributed to
`
`the residue layer. Therefore we can conclude
`
`that under our experimental conditions the ma-
`
`jor modifications by RIE are the formation of
`
`a 4 nm thick fluorocarbon residue layer on the
`
`silicon surface and a ~ 50 nm thick contami-
`
`nated silicon layer which contains carbon and
`
`fluorine atoms but no crystalline defect.
`
`Angle resolved XPS has been carried out
`
`for analyzing the distribution of chemical
`
`bonds in the residue film. The angle between
`
`sample surface and detector (take—off angle)
`
`varies from 15 to 75 degree. For the decon-
`
`volution of the spectra, the binding energies
`
`and the FWHMs in Table 1 are used.
`
`

`

`
`
`I5
`
`30
`
`45
`
`60
`
`75
`
`Take-Off Angle ( °)
`
`
`
`15
`
`30
`
`45
`
`60
`
`75
`
`Take-off Angle (~°)
`
`(b)
`
`Take-off angle dependencies of observed bonding
`species; (a) Si and (b) C.
`
`decrease and those of C-Si and C-C/H increase.
`
`Si substrate
`
`impurities penetrated
`region
`
`I Si-C
`
`Schematic diagram of reactive ion etched silicon
`surface.
`
`This implies that C—Si and C—C/H bonds exist
`
`under the C-F polymer layer. Since the sample
`
`is exposed to air for transfer to analyze, we have
`
`to always consider the physisorbed 1~2 mono-
`
`layer (ML) of carbOn on the top of the sample.
`
`This physisorbed carbon causes a decrease in
`
`Fig. 5 represents the variations of chemical
`
`slope with take-off angle. Then although the
`
`contributions to silicon and carbon with take—
`
`off angle. As the angle decreases, the contribu
`
`SlOpe change of C-Si is larger than C-C/H, we
`cannot say that the C-Si bond exists under the
`
`ti0n of the surface bonding state to the observed
`
`C-C/H bonds. With oxygen and fluorine, from
`
`peak intensity increases. From the comparison
`
`the cempariSOn of the slope changes for the area
`
`of slope changes of bonding contributions with
`
`% of each bond constituents, it can be said that
`
`take-off angle,
`
`the distribution of bondings
`
`can be defined. For silicon (Fig. 5(a)), Si-C
`
`O-F bond exists on the O-Si one and F-C bond
`
`exists between F-O and F-Si ones.
`
`bonding is found to be under the 81-0 bond,
`
`From these results, the schematic descript
`
`but above the silicon substrate.
`
`In Fig. 5(b),
`
`i0n of silicon Surface after RIE can be given
`
`area % of C—CFJr and C-Fy (y=1, 2, 3) slightly
`
`in Fig. 6. The physisorbed 1-2 ML of extra
`
`

`

`Atomic%
`
`Temperature ( 0C )
`
`. Composition change of the reactive ion etched
`
`silicon surface after rapid thermal anneal.
`
`Area%
`
`Temperature ( 0C)
`
`The variation of chemical contributions for C 15
`
`with anneal temperature.
`
`carb on has not been considered. At the surface,
`
`O-F bond over C-F polymer which mainly
`
`800°C. Decrease of C-C/H bond is faund due
`
`compo ses residue layer is found. Between the
`
`to the formation of Si-C bond between carbon
`
`C—F polymer layer and the Si substrate, C—C/H,
`
`and substrate silicon above 900°C.
`
`Si-C, Si-O, and Si-F bonds exist.
`
`Depth profile results using SIMS for the
`
`Fig. 7 shows a composition change of the
`
`annealed samples at 600°C and 800°C are pre-
`
`reactive ion etched silicon surface using XPS
`
`sented in Fig. 9. In Fig. 2, we have found that
`
`after RTA treatment under nitrogen atmosphere
`
`for 1 minute. After anneal above 800°C, flu—
`
`the thickness of contaminated silicon layer is
`~ 50 nm. RTA treatment at 600°C is revealed
`
`orine remains under 1 atomic percent. This
`
`to induce in-diffusion of C and F species to ~
`
`means that above 800°C, thermal decomposi-
`
`100 nm depth, but no in-diffusion phenomenoa
`
`tion of residue layer is completed.
`
`is observed for the 800°C treated specimen.
`
`Fig. 8 shows the variation of chemical con-
`
`This seems due to the fast decomposition of the
`
`tributions for C ls with annealing temperature.
`
`C—F residue film which remains on the surface
`
`As shown in Fig. 7, area percents of C-CFx and
`
`till 600°C and plays an important role of diffu-
`
`C—Fy bonds remain constant after anneal above
`
`sion source. With 800°C annealed sample, the
`
`

`

`ETRI Journal, volume 16, number i, April, “1995..
`
`silicon surface by XPS analysis after the treat-
`
`ments. And wet cleaning process has been ap-
`
`plied to all of the post etch treated samples.
`
`The remained fluorocarbon residue after every
`
`post etch treatments can be estimated from the
`
`changes of the fluorine and silicon composi*
`tions.
`
`Fig. 11 shows C Is (a) and F ls (b) peaks
`
`obtained after the 02 treatment. With the first
`
`1 minute exposure, the liberation of fluorine
`
`from fluorocarbon residue layer proceeds. For
`
`the C Is spectrum, the peaks corresponding
`
`to the C-Fy bondings continuously decrease
`
`and almost disappear after 10 minutes exPo—
`
`sure. The C- CFx contribution also decreases
`
`but after 2 minutes exposure, it becomes con-
`
`stant. It seems to be due to the appearance of
`
`C-0 bond which has nearly the same binding
`
`energy as C-CFX. With fluorine, according
`
`
`
`0
`
`400
`
`1200
`800
`Depth (angstrom)
`(a)
`
`1500
`
`2000
`
`E:1
`
`OUI
`
`:
`.9.
`
`E'«I
`'U
`I:
`OU
`)
`
`UU
`
`..
`
`1;,
`
`
`
`107
`
`U)
`:l
`10“
`E
`_
`O
`U 103
`O
`I—
`
`104
`
`r
`
`10
`
`b a
`
`c
`OU
`
`x 10=
`
`101
`
`o
`
`280
`
`560
`
`340
`
`1120
`
`1400
`
`to the exposure, the contribution of the F-0
`
`Depth (angstrom)
`(b)
`
`Fig.
`
`9.". Depth profile analysis using SIMS for annealed
`
`samples at (a) 600°C and (b) 800° C, for 1 minute,
`ICSpcclively.
`
`slightly increases and that of F-Si severely in—
`
`creases. The F—C bond is almost completely
`
`converted into F-Si bond above 20 minutes ex-
`
`posure to the 02 plasma. Above 10 minutes
`
`of exposure to the 02 plasma, the atomic %
`
`remains almost constant and the formation of
`
`secondary ion counts profile of carbon remains
`
`Si02 is almost saturated with 3-4 nm thickness.
`
`higher than that of fluorine. This may result
`
`These bonding states of the polymer film as
`
`from the almost remained carbon with C-C/H
`
`F—Si, C—0, and Si-O after the 02 treatment
`
`or Si-C bonds after anneal above 800°C.
`
`are found to be easily eliminated by succes-
`
`02, NF3, SF5, and C12 plasma treatments
`
`sive cleaning prooess. Through NF3, SF6, and
`
`have been carried out to remove the residue
`
`C12 treatments, no additional elements such
`
`layer as post etch treatments. Fig. 10 shows a
`
`as nitrogen, sulfur, and chlorine are detected.
`
`cumposition changes of the reactive ion etched
`
`Surface compositions drastically change after
`
`

`

`
`
`+wet
`
`Si
`
`+wet
`
`Si
`
`Composition changes of the reactive ion etched silicon surface after (a) 02, (b) NF3, (c) C12, and (d) SF6
`treatments.
`
`the treatments for 10 seconds, but maintain al-
`
`treatment, no fluorine is detected in the sample
`
`most constant with exposure times of 10 to 30
`
`treated using NF3 plaSma. With SF6 plasma,
`
`seconds. The effects of post etch treatments
`
`the atomic % of fluorine decreases to an half
`
`seem to be saturated within 10 seconds expo-
`
`value after the wet treatment, but with C12
`
`sure. AmOng the above three treatments, NF3
`
`treatment (Fig. 10 (b)) results in the smallest
`
`plasma it does not change.
`Fig. 12 represents the photoelectron Spec-
`
`fluorine atomic %. And after successive wet
`
`tra of fluorine after NF3, SF5, and C12 plasma
`
`

`

`10min
`
`2min
`
`1min
`
`l___4_.___.l_—_J
`280
`286
`292
`298
`
`Binding Energy / eV
`
`(a)
`
`(b)
`
`(C)
`
`l___.____|—....1—_..L___4
`68 l
`685
`689
`693
`697
`
`Binding Energy / eV
`
`Photoelectron spectra of fluorine after (a) NF3,
`
`(b) SF6 and (c) C1; plasma exposures for 10 sec-
`onds, respectively.
`
`20min
`
`same with that of just reactive ion etched sam-
`
`10min
`
`2min
`
`1 min
`
`l________l___J___.___l___._J
`681
`685
`689
`693
`697
`
`Binding Energy / eV
`
`ple. Fluorine mainly binds to carbon with a
`
`binding energy of ~ 689 eV. With SF5 plasma
`
`treatment, fluorine peak enlarges and peak po~
`
`sition moves to a low binding energy value
`
`comparing to that of C12 plasma treated sam-
`
`ple. This is due to the increase of F-Si bond
`
`contribution with a binding energy of 686.9
`
`eV. Increase of F-Si bond is clearly seen with
`
`NF3 plasma treated sample. Area of F-Si
`
`bond is nearly two times larger than that of
`
`Influence of 02 plasma treatment on (a) C Is and
`
`F—C bond. This chemical state change means
`
`(b) F 15.
`
`the decomposition of the residue layer and in-
`
`duces the easy removal of residue by succes-
`
`exposures for 10 seconds, respectively. The
`
`sive wet cleaning. These results show that NF3
`
`shape and bonds distributiOn of the fluorine
`
`plasma treatment is most effective to remove
`
`peak for C12 plasma exposure is almost the
`
`the residue layer on the reactive ion etched sil-
`
`

`

`icon surface.
`
`CGNCiUSlONS
`
`By cross-sectional HR’I‘EM analysis, about
`
`4 nm thick residue layer is observed on the re-
`
`active ion etched silicon surface in the CHF3
`
`/ C2F5 plasma.
`
`It is found that carbon in the
`
`fining-Ho Park. en .22.
`
`53
`
`to CHF; plasmas,” J. Electrochem. Soc, vol.135,
`
`no.6, pp. 1472-1477, 1988.
`
`[4]
`
`A. S. Yapsir, G. Fortuno-Wiltshire, T. P. Gambino,
`R. H. Kastl, and C. C. Parks, “Near surface damage
`
`and contamination of silicon following electron cy—
`
`clotron resonance etching," J. Vac. Sci. Technol. A,
`
`vol.8, no.3, pp. 2939-2944, 1990.
`
`[5]
`
`T. Kuroda and H. Iwakuro, “A study of CCl2F2
`
`magnetron ion etching damage and contamination
`effects in silicon,” Japan. J. AppL Phys, vol.29,
`
`residue layer consists of 6 chemical compo-
`
`no.5, pp. 923-929, 1990.
`
`nents as C—Si, C-C/I-I, C—CFx (x 5 3), OR,
`
`[6]
`
`X. C. Mu, S.
`
`J. Fonash, G. S. Oehrlein,
`
`OR, and C-F3 using XPS, SIMS, RBS / chan-
`
`neling, and HRTEM works show that ~ 50 nm
`
`thick contaminated silicon layer which con-
`
`tains mainly carbon and fluorine, has no ob—
`
`S. N. Chakravarti, C. Parks and J. Keller, “A study
`
`of CCng/Hz reactive ion etching damage and can-
`
`tamination effects in silicon,"J. Appl. Phys, vol.59,
`
`no.8, pp. 2958-2967, 1986.
`
`[7]
`
`D. Chu, “An integrated solution for reducing ox—
`
`servable amount of defect. With rapid thermal
`
`ide etchwrelated damage," Proc. Semicon/Korea
`
`anneal, iii-diffusion phenomenon of C and F
`
`Tech. Sympa., Seoul, Nov. 9-10, 1993, pp. 175-184.
`
`into the silicon lattice is found under 800°C.
`
`[3]
`
`K. Takase, T. Igarashi, N. Miyata, K. Moriki,
`
`NF3 treatment is revealed to be the most ef-
`
`fective post-etch treatment for removing the
`
`surface residue. Fluoroearbon residue layer
`
`R. Sugino, Y. Nara. T. Ito, M. Fujisawa and T. Hat-
`
`tori, “Native oxides formed during wet chemical
`
`treatments,” Free. 215: Int. Canfi on Solid State
`
`Devices and Materials, Tokyo, Aug. 28-30, 1989,
`
`decomposes with 10 seconds exposure to NF3
`
`pp. 393-396.
`
`plasma and completely disappears with succes-
`
`sive' wet cleaning.
`
`\
`
`.....r....-..._‘.
`.
`“1 r}
`_ orgy--24”. «‘
`
`[1] J. W. Coburn, “In situ Auger electron spectroscopy
`of Si and SK); surfaces plasma etched in CF4-
`
`H2 glow discharges,” J. Appl. Phys., Vol.50, no.8,
`
`pp. 5210-5213, 1979.
`
`[2] S. J. Fonash, “An overview of dry etching damage
`and contamination effects,” J. Electrochem. 300.,
`
`vol.137, no.12, pp. 3885-3892, 1990.
`
`[3] C. Cardinaud, A. Rhounna, G. Turban, and B. Grol-
`
`leau, “Contamination of silicon Surfaces exposed
`
`

`

`Hyung-Ho Park received
`the 8.8. degree from Han-
`
`yang University
`
`in
`
`1981,
`
`the M.S. degree from Korea
`Advanced Institute of Science
`
`
`
`. . degreeinmaterialscience from
`
`and Technology and the PhD.
`
`University of Bordeaux 1, France in 1988. Since 1989 he
`
`has been with the Semiconductor Technology Division
`of Electronics
`and Telecommunication Research
`
`Institute. His research areas of interest are surface
`
`.......
`
`Sang—Hwan Lee
`
`received
`
`the BS.
`
`and MS. degree
`
`from Kyungpook National
`
`University in 1981 and 1987,
`
`respectively. He joined in the
`
`
`
`Technology
`Semiconductor
`_
`Division of Electronics and
`'I .a
`Telecommunication Research Institute in 1987. His
`
`research areas were ion MeV beam analysis and ion
`
`implantatiOn damage until 1993.
`
`He is currently
`
`re5ponsible person of. opto-electronic device packaging
`
`and interface analysis of semiconducting materials and
`
`in Semiconductor Packaging Research Section.
`
`characterization of unit process for the preparation of
`
`semiconducting devices. He is currently responsible
`
`person of X—ray photoelectron spectrosc0py, Auger
`
`electron spectroscopy and scanning electron microscopy
`in Materials and Characterization Section.
`
`received
`Kwang-Ho Kwon
`the B.S., MS. and PhD. de-
`
`a senior member of technical Staff in the Process DeveloP-
`
`grees in electrical engineering
`
`from Korea University in 1985,
`1987, and 1993. He is currently
`
`ment Section of Electronics and Telecommunication Re-
`
`search Institute. His research field includes semiconduc-
`
`tor processing of application specific integrated circuits.
`
`His current interests are dry etching technologies.
`
`Byung-Hwa Koak received
`
`the B.S.(1980) and M.S.(1982)
`
`degrees
`
`in
`
`physics
`
`from
`
`Kyunghee University.
`
`Since
`
`Electronics and Telecommuni-
`
`1985 he joined in the Semicon—
`
`ductor Technology Division of
`
`catiOn Research Institute. His research areas of interest
`
`are surface and interface analysis of semiconducting
`
`materials and characterization of unit process for the
`
`preparation of semiconducting devices. He is currently
`
`responsible person of secondary ion mass spectrometer
`in Materials and Characterization Section.
`
`

`

`ETRI lournal, volume 16, number 1, April 1994
`
`Hyung—Ho Park, at al.
`
`57
`
`
`
`Sahn Nahm received the BS.
`
`degree from Korea University
`
`in 1983, and the PhD. degree in
`
`material engineering from Uni-
`
`versity of Maryland, USA in
`1990. He worked as Post Doc—
`
`toral Researcher in University
`
`Kyoung—Ik Cho received the
`
`BS. degree in materials sci-
`ence from Ulsan Institute of
`
`Technology in 1979, and the
`
`M.S. and PhD. degrees in ma- terials science and engineering
`
`In‘ ,3. \
`
`from Korea Advanced Institute
`
`of Maryland from Jan. 1991 to Dec. 1991. Since 1992
`
`of Science and Technology, in 1981 and 1991, respec-
`
`he has worked in the Semiconductor Technology Divi-
`sion of Electronics and Telecommunication Research In-
`
`tively. He joined the Electronics and Telecommunica—
`
`tion Research Institute (ETRI), Taejon in 1981. He is
`
`stitute. His interesting field of research is structural anal—
`
`currently a head of Materials and Characterization Sec-
`
`ysis of semiconducting materials, especially thin film and
`hetero-epitaxial multilayers. Now he is in charge of trans—
`
`mission electron microscope, X—ray diffraction and TEM
`Sample preparation labs in Mate rials and Characterization
`Section.
`
`tion in Semiconductor Technology Division at ETRI. His
`research interests include characterization of semiann-
`
`ducting materials, heteroepitaxy of semiconductor thin
`
`films, and structural analyses of heterointerfaces,
`
`flee-Tee Lee
`
`received the
`
`B.S. degree from National Cen-
`
`tral Vocational Training Insti-
`tute in 1978. Since 1981 he
`
`Technology Division of Elec- tronics and Telecommunica—
`
`has joined the Semiconductor
`
`tion Research institute. His research area of interest is
`
`
`
`Young-II Kang received the
`
`BS. degree in Electrical En-
`
`gineering from Seoul National
`
`University in 1966 and the M.S.
`
`degree from Fairleigh Dickson
`University in 1989. He joined
`Fairchild Semiconductor Ko-
`
`rea as a process engineer in 1969 and moved to Semicon-
`
`ductor Technology Division of. Electronics and Telecom—
`
`optical semiconducting device fabrication. He is cur—
`
`munication Research Institute.(ETRI) in 1979. He has
`
`rently working on optical device package.
`
`
`
`Oh-Joon Kwon
`
`received
`
`the 8.5. and M.S. degrees
`
`in electronic engineering from
`Kyungpook National Univer-
`
`sity in 1977 and 1989, respec—
`
`lively. He joined the Elec-
`tronics and Telecommunica—
`
`tion Research institute in 1977. He has worked in the
`
`areas of semiconductor process integration and character—
`
`izatiOn of semiconducting materials. He is now working
`on the development of microwave devices.
`
`worked in semiconductor process integration area for
`
`the most of his working time in both of Fairchild and
`
`ETRI. His current interests are failure analysis, new de-
`
`vice structure and process integratiOn. He is now working
`
`for the new antifused programmable read only memory
`
`device that can be implemented easily in the conventional
`
`c0mplementary metal oxide semiconduct0r process and
`
`can be easily integrated in the application specific inte—
`grated circuit families.
`
`