The role of crystallographic texture in electromigration resistance of interconnect lines is well documented. The presence of a strong (111) fiber texture results in a more reliable interconnect structure. It is also generally accepted that grain-boundary diffusion is the primary mechanism by which electromigration failures occur. It has been difficult to this point, however, to obtain statistically reliable information of grain-boundary structure in these materials as transmission electron microscopy investigations are limited by tedious specimen preparation and small, nonrepresentative, imaging regions. The present work focuses upon characterization of texture and grain-boundary structure of interconnect lines using orientation imaging microscopy, and particularly, upon the linewidth dependence of these measures. Conventionally processed Al–1%Cu lines were investigated to determine the affects of a postpatterning anneal on boundary structure as a function of linewidth. It was observed that texture tended to strengthen slightly with decreasing linewidth subsequent to the anneal procedure. Grain morphology changed substantially as the narrow lines became near bamboo in character and the crystallographic character of the boundary plane changed as a function of linewidth. These results are contrasted with those obtained from Al–1%Cu lines, which were fabricated using the damascene process. The damascene lines show a marked weakening in texture as the linewidth decreases, accompanied by a more random misorientation distribution. A description of the competing energetics, which result in the observed microstructures, is included.

1.
S.
Vaidya
and
A. K.
Sinha
,
Thin Solid Films
75
,
253
(
1981
).
2.
A. N.
Campbell
,
R. E.
Mikawa
, and
D. B.
Knorr
,
J. Electron. Mater.
22
,
589
(
1993
).
3.
D. B.
Knorr
,
Mater. Res. Soc. Symp. Proc.
309
,
75
(
1993
).
4.
D. B.
Knorr
and
K. P.
Rodbell
,
J. Appl. Phys.
79
,
2409
(
1996
).
5.
K. T. Lee, J. A. Szpunar, and A. Morawiec, Can. Metall. Q. 34, 225 (1995).
6.
O. V.
Kononenko
,
E. D.
Ivanov
,
V. N.
Matveev
, and
I. I.
Khodos
,
Scr. Metall. Mater.
33
,
1981
(
1995
).
7.
B. L. Adams, S. I. Wright, and K. Kunze, Metall. Trans. 24, 819 (1993).
8.
N. C.
Krieger-Lassen
,
K.
Conradsen
, and
D.
Juul-Jensen
,
Scanning Microsc.
6
,
115
(
1992
).
9.
S. I. Wright, J. Comput.-Assisted Microsc. 5, 207 (1993).
10.
S.
Kordic
,
R. A. M.
Wolters
, and
K. Z.
Troost
,
J. Appl. Phys.
74
,
5391
(
1993
).
11.
D. P. Field, D. J. Dingley, M. M. Nowell, and B. L. Adams, Proc. ISTFA 21, ASM International, p. 49 (1995).
12.
J. L.
Hurd
,
K. P.
Rodbell
,
D. B.
Knorr
, and
N. L.
Koligman
,
Mater. Res. Soc. Symp. Proc.
343
,
653
(
1994
).
13.
D. L.
Barr
,
W. L.
Brown
,
M. A.
Marcus
, and
M.
Ohring
,
Mater. Res. Soc. Symp. Proc.
391
,
347
(
1995
).
14.
S.
Matthies
and
G. W.
Vinel
,
Mater. Sci. Forum
157-162
,
1641
(
1994
).
15.
J.
Pospiech
,
K.
Sztwiertnia
, and
F.
Haessner
,
Textures Microstruct.
6
,
201
(
1986
).
16.
J-W.
Zhao
,
B. L.
Adams
, and
P. R.
Morris
,
Textures Microstruct.
8&9
,
493
(
1988
).
17.
D. P.
Field
and
D. J.
Dingley
,
J. Electron. Mater.
25
,
1767
(
1996
).
18.
J. K. Mackenzie, Biometrika 45, 229 (1958).
19.
C.
Turnbull
and
R. E.
Hoffman
,
Acta Metall.
2
,
419
(
1954
).
20.
A. P.
Sutton
and
R. W.
Balluffi
,
Acta Metall.
35
,
2177
(
1987
).
21.
T.
Watanabe
,
Mater. Sci. Forum
11
,
284
(
1988
).
22.
H. J.
Frost
,
Y.
Hayashi
,
C. V.
Thompson
, and
D. T.
Walton
,
Mater. Res. Soc. Symp. Proc.
338
,
295
(
1994
).
23.
D. Gupta, in Diffusion Phenomena in Thin Films and Microelectronic Materials, edited by D. Gupta and P. S. Ho (Noyes, Park Ridge, NJ, 1988), pp. 1–72.
24.
H.
Grimmer
,
H.
Bollmann
, and
D. D.
Warrington
,
Acta Crystallogr. Sect. A
30A
,
197
(
1974
).
25.
D. G.
Brandon
,
Acta Metall.
14
,
1479
(
1966
).
26.
W.
Liu
,
M.
Bayerlein
,
H.
Mughrabi
,
A.
Day
, and
P. N.
Quested
,
Acta Metall. Mater.
40
,
1763
(
1992
).
27.
P. R. Besser, J. E. Sanchez, Jr., and D. P. Field, Mater. Res. Soc. Symp. Proc. (to be published).
28.
P. R. Besser, J. E. Sanchez, Jr., and D. P. Field, Proc. Advanced Metallization for ULSI, 1996. To be published.
29.
F. C.
Frank
,
Metall. Trans. A
19
,
403
(
1988
).
30.
A.
Morawiec
and
D. P.
Field
,
Philos. Mag. A
73
,
1113
(
1996
).
31.
M.
McLean
and
B.
Gale
,
Philos. Mag.
20
,
1033
(
1969
).
32.
J. C. M.
Li
,
J. Appl. Phys.
33
,
2958
(
1962
).
33.
W. T.
Read
and
W.
Shockley
,
Phys. Rev.
78
,
275
(
1950
).
34.
A. H.
King
and
K. E.
Harris
,
Mater. Sci. Forum
204-206
,
355
(
1996
).
35.
V.
Randle
,
Acta Crystallogr. Sect. A
50
,
588
(
1994
).
36.
V.
Singh
and
A. H.
King
,
Scr. Metall. Mater.
34
,
1723
(
1996
).
37.
D.
Wolf
,
Acta Metall. Mater.
38
,
781
(
1990
).
38.
H. Mykura, in Grain Boundary Structure and Kinetics (American Society for Metals, Metals Park, OH, 1979), p. 445.
39.
D.
Wolf
,
Acta Metall. Mater.
38
,
791
(
1990
).
40.
H. J.
Frost
,
Y.
Hayashi
,
C. V.
Thompson
, and
D. T.
Walton
,
Mater. Res. Soc. Symp. Proc.
338
,
295
(
1994
).
41.
C. C.
Wong
,
H. I.
Smith
, and
C. V.
Thompson
,
Mater. Res. Soc. Symp. Proc.
47
,
35
(
1985
).
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