Semiconductor device manufacturing: process – Coating with electrically or thermally conductive material – To form ohmic contact to semiconductive material
Reexamination Certificate
2001-11-13
2004-07-06
Le, Dung A. (Department: 2818)
Semiconductor device manufacturing: process
Coating with electrically or thermally conductive material
To form ohmic contact to semiconductive material
C438S637000, C438S672000
Reexamination Certificate
active
06759327
ABSTRACT:
BACKGROUND OF THE DISCLOSURE
1. Field of the Invention
The invention relates to the fabrication of integrated circuits, more specifically to a process for depositing dielectric layers on a substrate, and to the structures formed by the dielectric layer.
2. Description of the Related Art
Semiconductor device geometries have dramatically decreased in size since such devices were first introduced several decades ago. Since then, integrated circuits have generally followed the two year/half-size rule (often called Moore's Law), which means that the number of devices that will fit on a chip doubles every two years. Today's fabrication plants are routinely producing devices having 0.35 &mgr;m and even 0.1 &mgr;m feature sizes, and tomorrow's plants soon will be producing devices having even smaller geometries.
To further reduce the size of devices on integrated circuits, it has become necessary to use conductive materials having low resistivity and to use insulators having low dielectric constants (dielectric constants of less than 4.0) to also reduce the capacitive coupling between adjacent metal lines. One such low k material is silicon oxycarbide deposited by a chemical vapor deposition process and silicon carbide, both of which may be used as dielectric materials in fabricating damascene features.
One conductive material having a low resistivity is copper and its alloys, which have become the materials of choice for sub-quarter-micron interconnect technology because copper has a lower resistivity than aluminum, (1.7 &mgr;&OHgr;-cm compared to 3.1 &mgr;&OHgr;-cm for aluminum), a higher current and higher carrying capacity. These characteristics are important for supporting the higher current densities experienced at high levels of integration and increased device speed. Further, copper has a good thermal conductivity and is available in a highly pure state.
One difficulty in using copper in semiconductor devices is that copper is difficult to etch and achieve a precise pattern. Etching with copper using traditional deposition/etch processes for forming interconnects has been less than satisfactory. Therefore, new methods of manufacturing interconnects having copper containing materials and low k dielectric materials are being developed.
One method for forming vertical and horizontal interconnects is by a damascene or dual damascene method. In the damascene method, one or more dielectric materials, such as the low k dielectric materials, are deposited and pattern etched to form the vertical interconnects, e.g., vias, and horizontal interconnects, e.g., lines. Conductive materials, such as copper containing materials, and other materials, such as barrier layer materials used to prevent diffusion of copper containing materials into the surrounding low k dielectric, are then inlaid into the etched pattern. Any excess copper containing materials and excess barrier layer material external to the etched pattern, such as on the field of the substrate, is then removed.
However, low k dielectric materials are often porous and susceptible to interlayer diffusion of conductive materials, such as copper, which can result in the formation of short-circuits and device failure. A dielectric barrier layer material is often disposed between the copper material and surrounding the low k material to prevent interlayer diffusion. However, traditional dielectric barrier layer materials, such as silicon nitride, often have high dielectric constants of 7 or greater. The combination of such a high k dielectric material with surrounding low k dielectric materials results in dielectric stacks having a higher than desired dielectric constant.
Therefore, there remains a need for an improved process for depositing dielectric barrier layer materials with low dielectric constants for damascene applications.
SUMMARY OF THE INVENTION
Aspects of the invention generally provide a method for depositing a barrier layer material having a low dielectric constant. In one aspect, the invention provides a method for processing a substrate including depositing a barrier layer on the substrate by introducing a processing gas comprising an organosilicon compound into a processing chamber, wherein the organosilicon compound has the formula SiH
a
(CH
3
)
b
(C
6
H
5
)
c
, wherein a is 0 to 3, b is 0 to 3, and c is 1 to 4, and reacting the processing gas to deposit the barrier layer, wherein the barrier layer has a dielectric constant less than 4 and depositing a first dielectric layer adjacent the barrier layer, wherein the dielectric layer comprises silicon, oxygen, and carbon and has a dielectric constant of about 3 or less.
In another aspect, a method is provided for processing a substrate including depositing a barrier layer on the substrate by introducing a processing gas comprising an organosilicon compound into a processing chamber, wherein the organosilicon compound has the formula SiH
a
(CH
3
)
b
(C
6
H
5
)
c
, wherein a is 1 or 2, b is 1 or 2, and c is 1 or 2, and reacting the processing gas to deposit the barrier layer, wherein the barrier layer has a dielectric constant of less than 4 and depositing a dielectric layer adjacent the barrier layer, wherein the dielectric layer has a dielectric constant less than 4.
REFERENCES:
patent: 4262631 (1981-04-01), Kubacki
patent: 4532150 (1985-07-01), Endo et al.
patent: 4634601 (1987-01-01), Hamakawa et al.
patent: 4759947 (1988-07-01), Ishihara et al.
patent: 4894352 (1990-01-01), Lane et al.
patent: 5011706 (1991-04-01), Tarhay et al.
patent: 5224441 (1993-07-01), Felts et al.
patent: 5238866 (1993-08-01), Bolz et al.
patent: 5242530 (1993-09-01), Batey et al.
patent: 5465680 (1995-11-01), Loboda
patent: 5494712 (1996-02-01), Hu et al.
patent: 5554570 (1996-09-01), Maeda et al.
patent: 5607773 (1997-03-01), Ahlburn et al.
patent: 5638251 (1997-06-01), Goel et al.
patent: 5710067 (1998-01-01), Foote et al.
patent: 5711987 (1998-01-01), Bearinger et al.
patent: 5730792 (1998-03-01), Camilletti et al.
patent: 5776235 (1998-07-01), Camilletti et al.
patent: 5780163 (1998-07-01), Camilletti et al.
patent: 5818071 (1998-10-01), Loboda et al.
patent: 5876891 (1999-03-01), Takimoto et al.
patent: 5926740 (1999-07-01), Forbes et al.
patent: 5989998 (1999-11-01), Sugahara et al.
patent: 6051321 (2000-04-01), Lee et al.
patent: 6054379 (2000-04-01), Yau et al.
patent: 6060132 (2000-05-01), Lee
patent: 6068884 (2000-05-01), Rose et al.
patent: 6072227 (2000-06-01), Yau et al.
patent: 6140226 (2000-10-01), Grill et al.
patent: 6147009 (2000-11-01), Grill et al.
patent: 6159871 (2000-12-01), Loboda et al.
patent: 6242339 (2001-06-01), Aoi
patent: 6287990 (2001-09-01), Cheung et al.
patent: 6303523 (2001-10-01), Cheung et al.
patent: 6312793 (2001-11-01), Grill et al.
patent: 6340435 (2002-01-01), Bjorkman et al.
patent: 6344693 (2002-02-01), Kawahara et al.
patent: 6348725 (2002-02-01), Cheung et al.
patent: 6352945 (2002-03-01), Matsuki et al.
patent: 6383955 (2002-05-01), Matsuki et al.
patent: 6410463 (2002-06-01), Matsuki
patent: 6432846 (2002-08-01), Matsuki
patent: 6436824 (2002-08-01), Chooi et al.
patent: 6455445 (2002-09-01), Matsuki
patent: 6465366 (2002-10-01), Nemani et al.
patent: 6500773 (2002-12-01), Gaillard et al.
patent: 6555476 (2003-04-01), Olsen et al.
patent: 2002/0093075 (2002-07-01), Gates et al.
patent: 2002/0111042 (2002-08-01), Yau et al.
patent: 2002/0160626 (2002-10-01), Matsuki et al.
patent: 2003/0001282 (2003-01-01), Meynen et al.
patent: 2003/0003765 (2003-01-01), Gibson, Jr. et al.
patent: 2003/0085408 (2003-05-01), Yang et al.
patent: 2003/0089988 (2003-05-01), Matsuura
patent: 2003/0111730 (2003-06-01), Takeda et al.
patent: 2003/0129827 (2003-07-01), Lee et al.
patent: 2003/0139035 (2003-07-01), Yim et al.
patent: 199 04 311 (1999-08-01), None
patent: 1 107 303 (2001-06-01), None
patent: 1 176 226 (2002-01-01), None
patent: 09-008031 (1997-01-01), None
patent: 99/41423 (1999-08-01), None
patent: 00/19498 (2000-04-01), None
U.S. patent application No. 09/270,039, filed on Mar. 16, 1999.
Written Opinion from PCT/US99/22424, dated Apr.
Xia Li-Qun
Xu Ping
Yang Louis
Applied Materials Inc.
Le Dung A.
Moser Patterson & Sheridan
LandOfFree
Method of depositing low k barrier layers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of depositing low k barrier layers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of depositing low k barrier layers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3252512