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Моделирование структуры поверхности и численный расчет плотности тока полевого эмиссионного металлического катода.

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.-..JK 537.533
K. A .
BeCTHI1K CTI6fY. Cep. 10, 2006, Bbln. 2
H. B.
HU'K:UifjOP06,
E20P06
M O,LI;EJIlIPOBAHlIE CTPYKTYPbI IlOBEPXHOCTlI
11 -qllCJIEHHblM PAC-qET llJIOTHOCTlI TOKA
IIOJIEBOrO 9MlICClIOHHOrO METAJIJIlI-qECKOrO KATO,LI;A
1. BBe,n;eHHe.
IIoJIeBo:i1: 3MHCCHOHHbI:i1: KaTO,n; 51BJI5IeTC5I O,n;HHM H3 nepcneKTHBHbIX HC­
[lJ.
TO':IHHKOB 3JIeKTpOHOB ,n;JI5I YCKopHTeJIbHo:i1:'TexHHKH
OTCYTcTBHe npe,n;BapHTeJIbHOrO
B036Y)K,n;eHH5I 3JIeKTpOHOB, OTJIH':IaIOIII,ee nOJIeBYIO 3JIeKTpOHHYIO 3MHCCHIO (II99), ,n;eJIaeT
CTIeKTp BbIIIIe,n;IIIHX 3JIeKTpOHOB ,n;OCTaTO':lHO y3KHM H, KaK CJIe,n;cTBHe, pa36poc no CKOpOC­
TIl M He3Ha':lMTeJIbHbIM
[2J.
B TO BpeM5I KaK HMeeTC5I 60JIbIIIOe KOJIH':IeCTBO pa60T no Mo,n;eJIMpOBaHHIO HOHHoro OCT­
p UHHord 3MMTTepa Hero 3MHCCMOHHbIX H306p~eHHH
[3],
aHaJIorM':IHM Mo,n;eJIb nOJIeBOrO
~~ eKTpOHHoro KaTo,n;a B OTe':leCTBeHHo:i1: H 3apy6e)KHo:i1: JIHTepaType npe,n;CTaBJIeHa TOJIbKO
p a3pa60TKaMH rpynnbI
A. JI.
CYBopoBa
[4J.
B 3TO:i1: e,n;MHcTBeHHoH H3 npe,n;JIO)KeHHbIX MeTO­
.:IU K <popMa nOBepXHOCTH KaTo,n;a HrHopHpyeTC5I, a OCTPH:i1:HbIH 06pa3eIJ; annpoKcHMHpyeTc5I
l:IeKOTOpbIM a6cTpaKTHbIM MHororpaHHMKOM, He COOTBeTCTBYIOIII,HM peaJIbHOH cHTyau;HH
[5J.
B HaCT05lIII,e:i1: CTaTbe npe,n;JIO)KeHbI Mo,n;eJIb KPHCTaJIJIH':IeCKOH CTpyKTYPbI nOBepXHOCTH H
DOCTpoeHHe KPHCTaJIJIOrpa<pH':IeCKHX rpaHe:i1: C Pa3JIH':IHbIMH 3Ha':leHH5IMH pa60TbI BbIxo,n;a Ha
sepIIIMHe KaTo,n;a. ,II;aHHa51 Mo,n;eJIb n03BOJI5IeT BbI':IHCJIHTb pacnpe,n;eJIeHHe nJIOTHOCTM TOKa
H nJIOIII,a,n;b 3MMCCHM Hanp5lMYIO, B OTJIH':IHe OT Tpa,n;HIJ;HOHHOro no,n;xo,n;a, HCnOJIb3YIOIIJ;erO
cpe,n;HeB3BeIIIeHHoe 3Ha':leHHe pa60TbI BbIxo,n;a
2. «PH3H'IeCKaj{ Mo,n;eJIb.
[6J.
OCHOBHa51 ,n;JI5I II99 3aBHCHMOCTb nJIOTHOCTH TOKa OT Ha­
Ilp 51)KeHHOCTM 3JIeKTpH':IeCKOrO nOJI5I, BbI3bIBaIOIII,erO 3MMCCHIO, TeOpeTH':IeCKH paCC':IHTbIBa­
eTC5I npM cTaH,n;apTHblx <pM3M':IeCKHX npe,n;nOJIO)KeHH5IX
[7J:
1)
3HepreTM':IeCKHe 30HbI B MeTaJIJIe onHCbIBaIOTC51 npM6JIM)KeHHeM cB060,n;HbIX 3JIeK­
2)
COCT05lHHe
TPOHOB;
3JIeKTpOHHoro
ra3a
onHCbIBaeTC5I
KBaHToBo:i1:
CTaTMcTMKo:i1:
<I>epMH­
,II;HpaKa;
3)
a6COJIIOTHa51 TeMnepaTypa paBHa HyJIIO;
4)
5)
nOBepxHocTb MeTaJIJIa 51BJI51eTC5I nJIOCKOH M rJIa,n;Ko:i1: B aTOMHbIX MacIIITa6ax;
pa60Ta BbIxo,n;a 3JIeKTpOHa nOCT05lHHa no 3MHTTMpYIOIII,e:i1: nOBepXHOCTM H He 3aBHCHT
OT BHeIIIHero nOJI5I;
6)
7)
3JIeKTpH':IeCKOe nOJIe O,n;HOPO,n;HO Ha,n; 3MHTTHpyIOIII,eH nOBepXHOCTbIO;
B3aMMo,n;e:i1:cTBMe 3MHTHpOBaHHbIX 3JIeKTpOHOB C nOBepXHOCTbIO onMCbIBaeTC51 KJIaCCH­
':IeCKHM nOTeHIJ;MaJIOM H306p~eHH5I;
8)
K03<P<PHIJ;HeHT npOXO)K,n;eHH5I nOTeHIJ;MaJIbHOrO 6apbepa onpe,n;eJI5IeTC51 no MeTO,n;y
BeHIJ;eJI5I-
K paMepca - B pI1JIJII03Ha.
paMKax CTaH,n;apTHbIX npe,n;nOJIO)KeHH:i1: nOJIY':leHO aHaJIHTH'feCKOe Bblp~eHHe ,n;JI5I
B
n.l0THOCTH TOKa
[8J
AF2
j(F) = <Pt 2 (y)
3,.'l.eCb
F -
A
H
B -
nOCT05lHHble MHO)KHTeJIM,
exp
(<P3/2
)
-Bpv(y) .
t(y), v(y) -
(1)
3JIJIMnTM':IeCKHe <PyHKu;HH Hop,n;re:i1:Ma,
Hanp51)KeHHOCTb BHeIIIHero 3JIeKTpH':IeCKOrO nOJI51,
<p -
pa60Ta BbIxo,n;a MaTepHaJIa, 5lB­
.15lIOIII,MC5I Mepo:i1: 3HeprHH CB5I3H 3JIeKTpOHOB C TBep,n;bIM TeJIOM.
© K. A.
HI1KI1<pOPOB , H. B. EropoB, 2006
39
ITJIOTHOCTb TOKa
j
H Harrp5DKeHHOCTb rrOJI5I
F
rrpaKTW-IeCKH He H3Mep5IIOTC5I OrrbITHbIM
rryTeM, a 3KcnepHMeHTaJIbHble 3aBHCHMOCTH CTP05lTC5I 06bI'fHO Me1K,lI,y rrOJIHbIM TOKOM IT99
I
H Harrp5I1KeHHeM
V:
1=
J
(2)
jdS,
(5)
r,ll,e
S -
rrJIOIll,a,D,b 3MHCCHH;
(3 -
reOMeTpH'feCKHH <paKTOP rrOJI5I, 3aBHC5IIlI,HH OT <pOPMbI
KaTO,ll,a.
OCHOBHa51 TPY,ll,HOCTb , B03HHKaIOIlI,a51 rrjm rrpOBe,ll,eHHH KOJIH'feCTBeHHoro aHaJIH3a H3­
MepeHHH IT99, CB5I3aHa C HeY,lI,06uOH <pOPMOH 3MHTTepa -
3MHTTHpyIOIlI,a51 rroBepxHocTb
HaxO,ll,HTC5I B 06JIC1CTH 60JIbiliOH KpHBH3HbI, 'fTo6bI rrpH cpaBHHTeJIbHO He60JIbIlIllX Harrp5I­
1KeHH5IX C03,l1,aTb Heo6xo,ll,llMYIO ,lI,JI5I IT99 Harrp5I1KeHHOCTb rrOJI5I. ITPH pa,ll,Hyce BepIlIllHbI
6
8
4
OCTpH5I 3MHTT epa OKOJIO 10- -;- 10- M H Uarrp5I)KeHllH OKOJIO 10 3 -;- 10 B Harrp5l1KeHHOCTb
6
8
rrOJI5I Ha BepuIHue ,lI,OCTHraeT Heo6xo,ll,HMbIX 3Ha'feHHH - He MeHee npHMepHo 10 -;- 10 B/M.
B pe3YJlbTaTe HapYilialOTc5I CTaH,lI,apTHble <p1l3H'feCKHe rrpe,ll,rrOJI01KeHll51 - reOMeTpH'feCKHH
<paKTOp rrOJI5I
(3
H 3Ha'feHll51 pa60TbI BbIXO,ll,a <I> H3MeH5IIOTC5I rro 3MllTTllpYlOIlI,eH rroBepxHocTll ,
3MHTTHPYlOIlI,a5I rrOBepxHocTb
S
3aBllCllT OT rrpHJI01KeHHoro Harrp5l1KeH1l5l , CTaHOBHTC5I HeB03­
M01KHbIM rrp5lMOe orrpe,ll,eJIeHlle BeJIH'fHH, BXO,ll,5lIll,HX B
(2).
HecMoTp51 Ha TO, 'fTO MeTO,ll,llKa corrOCTaBJIeHH5I pe3YJIbTaTOB TeopllH 11 3KcrrepHMeHTa rro
<popMYJIaM
(1), (2)
C rrO,ll,CTaHOBKoH rrOCT05lHHbIX 3Ha'feHHH <I> 11
S
51BJI5IeTC5I 06Il1,errpllH5ITOH ,
ee Bp5l,ll, JIH M01KHO C'fHTaTb ,lI,OCTaTO'fHO KoppeKTHoH .
ITPH TaKOM COIIOCTaBJIeHHll Heo6xo­
,lI,llMO rrepeXO,ll,HTb OT H3MepeHHbIX Ha orrbITe BeJIH'fllH
I
11
V
K xapaKTepllCTHKaM
j
F,
H
'fTO rrpe,ll,JIaraeTC5I oCYIll,eCTBHTb C rrOMOIll,bIO MaTeMaTll'feCKOro MO,ll,eJIllpOBaHll51 peaJIbHOll
KOH<pllrypaIJ;llH rrOJIeBOrO 3JIeKTpOHHoro KaTO,ll,a, rroBepxHocTb BepIlIllHbl KOToporo COCTOHT
H3 rrJIOCKllX 06JIaCTeH, cooTBeTcTBYIOl11,l1X XOPOiliO orrpe,ll,eJIeHHbIM KPllCTaJIJIOrpa<pH'feCKHM
rpaH5IM.
3.
MaTeMaTIPlecKajl Mo.n;eJIb.
3.1. Annp01CCUMa'4UJl, fjjOPM'bt n06epX1-tOCmu U pacnpeae.l/,e1-tue 3.1/,e1Cmpu"tec­
n020 no.l/,Jl, namoaa. <I>opMa rroBepxHocTH KaTO,ll,a 11 pacrrpe,ll,eJIeHlle MaKpOCKOrrH'feCKOrO
3JIeKTpH'feCKOrO rrOJI5I y rroBepxHocTll npe,ll,CTaEJI5IIOTC5I MO,ll,eJIblO «c<pepa Ha KOHyce»
9KBllrrOTeHIJ;HaJIbHa51 rrOBepXHOCTb (pHC.
1)
[9].
3JIeKTpll'feCKOrO rroJI5I, KOTopoe C03,l1,aHO 3a­
p5l1KeHHbIM opTOrOHaJIbHbIM KOHyCOM co c<pepoH Ha BepIlIHHe, rrpHHllMaeTC5I 3a 3MllTTep,
,lI,pyra51 - 3a aHO,ll,. Pacrrpe,ll,eJIeHHe rrOTeHIJ;HaJIa ,lI,aeTC5I B c<pepH'feCKOH CllCTeMe KOOp,ll,HHaT
Bblpa1KeHHeM
Vr
V = R~ (rn - a2n+lr-n-l)Pn(cosO).
B
(3) R -
paCCT05lUHe ,lI,O alIO,ll,a,
a -
pa,ll,Hyc C<pePbI,
Pn
-
(3)
<PYHKu;H5I JIe1KaH,lI,pa rrepBoro
n, npll'feM n HaX0,ll,l1TC5I1l3 YCJIOBH5I Pn(cos ( 0 ) = 0, Vo r ;::::: R/(Pn(cosO))l/n, V = 0 Ha rroBepxHocTH KOHyca 11 C<pePbI.
pO,ll,a rrOp5l,ll,Ka
rrOTeHIJ;HaJI Ha aHO,ll,e
Harrp5l1KeHHOCTb MaKpOCKOrrll'feCKoro 3JIeKTpll'feCKOrO nOJI5I paEHa
Fmacro
= Vo
(nrn
+ (n + 1)a2n+lr-n-l )2 (Pn(COS 0))2 R2nr2
(
+
1
+
40
(a2n+lr-n-l _ rn)2(n + 1)2(cos OPn(COS 0) - Pn+l(COSO))2) "2
R2nr2 sin 2 0
PaCCTo}IHHe, X
10-7 M
4
3
2
1
o
Puc. 1.
AIllIpoKCHMa~g <pOPMbl OlMHT­
-1
Tepa rrpH HCrrOJIb30BaHHH Mo,n;eJIH «c<pepa
Ha KOHyce».
a = 120 . 10- 9
0,04
M,
M,
p~HyC
=
KpHBH3HhI Bep­
239 . 10- 9
n = 0,14 (00 ~ 177°).
3MHTTepa TO
WHHbl
M,
R
=
-4
-2
o
PaCCTOHHl1e, X
2
10-7 M
HaJIl1'·u:le Ha nOBepXHOCTl1 HepOBHOCTeM aTOMHOrO MaCIIITa6a npl1BO,n;l1T K TOMy, 'ITO JIO­
KaJIbHOe ::meKTpl1'IeCKOe nOJIe F Henocpe,n;CTBeHHO Y nOBepXHOCTl1 (Ha paCCTO.HHl1l1 npl1­
9
MepHo 2 . 10- M) 'IacTO 6bIBaeT 3Ha'Il1TeJIbHO 60Jiliwe MaKpOCKOnl1'IeCKOrO nOJI.H Fmacro
[10].
KpoMe Toro, MaKpOCKOnl1'IeCKOe nOJIe peaJIbHOM nOBepxHocTH npeTepneBaeT 113MeHe­
HH.H B,n;OJIb nJIOCKHX KPHCTaJIJIOrpaq:lH'IeCKHX rpaHeM.
I1pe,n;JIaraeTC.H HCnOJIb30BaTb e,n;HHbIM HHTerpaJIbHbIM napaMeTp, xapaKTep113YIO~HM we­
pOXOBaTOCTb nOBepxHocTH Ha aTOMHOM ypOBHe H Y'IHTbIBaIO~HM JIOKaJIbHble H3MeHeHH.H
nOJI.H:
(4)
r,n;e K03<P<PHI1,l1eHT YCHJIeHH.H JIOKaJIbHOrO nOJI.H ,
.HBJI.HeTC.H no,n;rOHO'IHbIM napaMeTpoM MO­
,n;eJIH.
3.2. Mooe,lf,'b zeOMempuu n08epXHocmu u npucma,lf"lf,ozpaifju"tecnou aHU30­
mponuu pa6om'bl. 8'bl.XOoa. KPHCTaJIJIOrpa<pH'IeCKHe rpaHH, 06pa:3YIO~l1e nOBepXHOCTb
3MHTTepa, onpe,n;eJI.HIOTC.H no pacnOJIO)KeHHIO nOBepXHOCTHbIX aTOMOB, Ka)K,n;bIM H3 KOTOPbIX
B Mo,n;eJIH «JIOKaJIbHOrO aTOMHoro oKPY)KeHl1.H» y,n;oBJIeTBOp.HeT COOTHoweHHIO
Ni
B KOTOPOM
Ni -
i-ro nOp.H,n;Ka,
:::;
Nr ax -1
(i = 1, ... ,M),
'IHCJIO coce,n;Hl1X aTOMOB i-ro nOp.H,n;Ka,
M -
Ni ax
(5)
- MaKCl1MaJIbHOe 'IHCJIO coce,n;eH
MaKCHMaJIbHbIH nOp.H,n;oK aHaJIH311pyeMblx coce,n;eM.
Koop,n;HHaTbI nOBepxHocTHbIX aTOMOB H~yTC.H no aJIropHTMy
[11],
l1cnOJIb3yIO~eMy MO­
,n;eJIb «TOHKOM o6oJIo'IKl1.» 11 Mo,n;eJIb «nopBaHHbIX CB.H3eM» HJIH «JIOKaJIbHOrO aTOMHoro OKpy­
)KeHH.H» B npe,n;nOJIO)KeHHH l1,n;eaJIbHOH KPHCTaJIJIH'IeCKOM peWeTKl1. MCXO,n;HbIMH ,n;aHHbIMH
.HBJI.HIOTC.H cTpyKTypa peweTKH Kpl1CTaJIJIa, <popMa nOBepxHocTH H opHeHTaIIH.H Kpl1CTaJIJIa.
B
no,n;xo,n;e «nopBaHHbIX CB.H3eH» KPl1CTaJIJIOrpa<pH'IeCKa.H aHH30TpOnH.H pa60TbI BbIxo,n;a
JIHHeHHO annpOKCl1MHpyeTC.H no napaMeTpy
6t
= t-
- t+ [12],
COCTaBJI.HIO~He
KOToporo ,n;JI.H
o6'beMHO-IIeHTpHpoBaHHOH Ky6H'IeCKOH perueTKH HMeIOT Bl1,n;
_
37f(h + k + I)
b.c.c. - 8Q2(h2 + k2 + Z2)3/2 a '
t-
t+
_
b.c.c. -
{
0,472h
Q2(h 2 + k 2 + [2)3/2 a '
0,236(h + k + I)
Q2(h 2 + k 2 + Z2)3/2 a '
h - k -I
< 0,
h - k -I
~
0,
41
Q
r,n;e
h, k, 1 -
={
1,
2,
+ k + 1 = 2n, n E N,
h + k + 1 = 2n + 1, n E N,
h
l1H,LI,eKCbI Ml1JIJIepa KPl1CTaJIJIOrpa<pl1'-:leCKOii rpaHl1;
K03<p<pl1l.I,l1eHT KOppeJI.HIIl1l1 JIl1HeiiHOii perpeCCl1ll no
paBeH
6t
a -
napaMeTp peIlleTKl1.
,n;JI.H BOJIb<ppaMa np116JI11311TeJIbHO
0,9638.
3a,n;a'Ia onpe,n;eJIeHl1.H KPl1CTaJIJIOrpa<pl1'IeCKl1X rpaHeii no pacnOJIO)KeHl1IO nOBepXHOCT­
HbIX aTOMOB CBOMTC.H K pacn03HaBaHl11O 3JI~MeHTapHoii .H'IeiiKl1 11 OCJIO)KH.HeTC.H HaJIl1'Il1eM
Kpl1B113HbI nOBepXHOCTl1 KaTO,Ll,a. BOJIee npOCToe peIlleHl1e OCHOBaHO Ha TOM, 'ITO aTOMbI, l1Me­
IOIlI,l1e l1,n;eHTl1'IHOe reOMeTpl1'IeCKOe OKpY)KeHl1e, paBHoy,n;aJIeHbI OT pa3,n;eJI.HIOIlI,eii nJIOCKOCTl1
nOBepXHOCTl1 Kpl1CTaJIJIa, KaK HeTpy,n;HO nOKa3aTb.
ll,Ll,eHTl1'IHoe reOMeTpl1'IeCKOe OKpY)Ke­
Hl1e 03Ha'iaeT HaJIl1'Il1e OMHaKOBoro KOJIl1'IeCTBa 6JIl1)KaiiIlll1X coce,n;eii JIIo6oro nOp.H,n;Ka.
3
,lJ,JI.H nOJIyc<pepl1'IeCKl1X KPl1CTaJIJIOB pa,n;l1yCOM OKOJIO 1 . 10 napaMeTpOB peIlleTKl1 C
06'beMHO-IIeHTpl1pOBaHHOii Ky611'IeCKOii CTPYKTypoii ,n;OCTaTO'IHO OrpaHl1'Il1TbC.H coce,n;.HMl1,n;o
n.HTorO nop.H,LI,Ka BKJIIO'Il1TeJIbHO, TaK KaK Y'IeT coce,n;eii 60JIee BbICOKoro nop.H,n;Ka BHOCl1T
nOnpaBKl1 MeHee
1%
Ha aToMHYIO 'Il1CJIeHHOCTb rpaHeii (Pl1c.
2).
K~,n;a.H KPl1CTaJIJIOrpa<pl1'IeCKa.H rpaHb 06JIa,n;aeT nOCTO.HHHbIM 3Ha'IeHl1eM pa60TbI BbI­
xo,n;a, CJIe,Ll,OBaTeJIbHO, npn paC'IeTe no <popMYJIe
(1)
nJIOTHOCTl1 TOKa 3Ml1CCl1l1 C rpaHl1 CHl1­
MaeTC.H npOTl1BOpe'Il1e n.HToMY cTaH,n;apTHoMY <p11311'IeCKoMY npe,LI,TIOJIO)KeHl1lO.
4. IIpoBepKa a,n;eKBaTHOCTll Mo,n;eJIll Ha OCHOBe ,n;aHHbIX HaTypHoro 3Kcnep"­
MeHTa: BOJIbT-aMnepHbIe xapaKTep"CT"K" KaTo,n;a II nJIo:rn;a,n;b 3MllCCllll. 06Il1,l1ii
TOK 3Ml1CCl1l1 B c<pepl1'IeCKl1X KOOp,Ll,l1HaTaX onpe,n;eJI.HeTC.H 113 <POPMYJI
J(V) =
3,L1,eCb TO -
{27f {7f/2 AF2
<I>t2(y)
10 10
exp
(<I>3/2
)
-Bpv(y)
pa,n;l1Yc Kpl1B113HbI BepIlll1HbI 3Ml1TTepa.
(1), (2):
T6 cos()sin()dt.pd().
LIl1CJIeHHOe l1HTerpl1pOBaHl1e np0113BO­
,n;l1TC5I MeTO,Ll,OM KBa,n;paTYp Cl1MnCOHa.
IIapaMeTp nO,Ll,rOHKl1 Mo,n;eJIl1 - K03<P<P11IIl1eHT yCl1JIeHl1.H JIOKaJIbHOrO nOJI5I
r - onpe,n;eJI.H­
eTC.H 113 conOCTaBJIeHl1.H 3KCnepl1MeHTaJIbHbIX 11 Mo,n;eJIl1pyeMblx BOJIbT-aMnepHbIX xapaKTe­
Pl1CTl1K KaTo,n;a. ,lJ,JI.H BOJIb<ppaMOBoro 3JIeKTpOHHoro 3Ml1TTepa xapaKTepl1CTl1Kl1 COBna,n;aIOT
C norpeillHOCTbIO He 60JIee
,n;aHHbIM
5%
npl1 3Ha'IeHl1l1
r ""
1,5,
cooTBeTcTBYIOIlI,eM JIl1TepaTypHbIM
[10].
9KCnepl1MeHTaJIbHOe 3Ha'IeHl1e nJIOIll,a,n;l1 3Ml1CCl1l1
A
,LI,JI5I BOJIb<ppaMoBoro KaTO,Ll,a no­
JIY'IeHO 113 3Ml1CC110HHOrO 11306pa)KeHl1.H (cnpaBa OT KPl1BOii Ha pl1C.
3)
COrJIaCHO <popMYJIe
[6]
r,n;e pa,Ll,l1Yc Kpl1B113HbI T BepIlll1HbI 3KCnepl1MeHTaJIbHOrO OCTpl1.H OIIeHl1BaeTC5I 113 Hanp.H)Ke­
5
Hl1.H, Heo6xo,n;l1MOrO ,n;JI.H nOJIY'IeHl1.H o6Il1,ero 3Ml1CC110HHOrO TOKa:
paCCT05lHl1e Me)K,Ll,Y IIeHTpaMl1
(211)
11
(121) (
l1JIl1
(211)
11
(121))
J = 1 . 10-
A [13];
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Summary
Nikiforov K. A., Egorov N. V. The simulation of surface structure and current density calculation
of a field emission metal cathode.
The computer model of a field electron emission metal cathode (radius of curvature near 100
nm) is proposed. Crystal surface is assumed to be ideal. Lattice geometry for given emitter shape
is calculated in "thin shell" and "broken bonds" models. The model "sphere on cone" is used for
cathode shape and macroelectric field distribution. Local field enhancement factor is the fitting
parameter of a model. Local work function values are found in the "broken bonds" approach from
atom packing density in the local area of the surface. Model current density, total emission current,
emission area and simulated field emission images are compared with experimental results.
JIMTepaTypa
r.
1. Eeopo6 H. E., Kapno6 A.
,LJ;HaI'HOCTH'leCKHe HH<pOPMaIIHOHHo-3KcnepTHble CHCTeMbl.
CfI6.: J-bp,-BO C.-IIeTep6. YH-Ta, 2002. 472 c.
44
2. MooU'l-tOc A. ABTO-, TepMO- H BTOPWIHO-3JIeKTpOHHMI 3MHCCHOHHaa crreKTpoCKOIllla I I1ep.
c aHrJI. r. H. <Dypcea. M.: HayKa, 1990. 320 c.
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9HeproaToMH3,n;aT, 1990. 296 c.
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11. Hu'X:urjiopo6 K. A. Mo,n;eJIHpOBaHHe KPHCTaJIJIH'leCKOn CTpyKTYPbI rroBepxHocTH MeTaJIJIH­
qeCKOro KaTo,n;a I I I1pou;eccbI yrrpaBJIeHHa H YCTon'lHBOcTb: Tpy,lI;bI XXXV Hay'l. KOH<pepeH:o;HH
<PaKYJIbTeTa I1M- I1Y. CI16., 2004. C . 244-247.
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transitional metals I I Phys. Stat. Sol. A. 2001. Vol. 183. P . 307- 322.
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missionsmikroskopen sowie Methoden zur Bestimmung desSpitzenradius, der Spitzenform, der
VergroBerung und des Auflosungsvermogens I I Z. Angew. Phys. 1954. Bd 6. S. 341-346.
14. PYOHU'll,'X:UU JI. A . 0 pa60Te Bblxo,n;a 3JIeKTpOHa H ,n;OHopHo-aKu;errTopHhlx cBoncTBax He­
H,n;eaJIbHbIX HJIH rrOKpbITbIX a,n;'laCTHu;aMH rroBepXHocTen MeTaJIJIOB I I IbB. AH CCCP. Cep. <pH3 .
1982. T. 26. C. 1240-1246.
CTaTMI 110CTYI1HJ1a B peAaK~luo 11 AeKa6pB 2005 r.
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