US20130328202A1 - Through-silicon via and fabrication method thereof - Google Patents
Through-silicon via and fabrication method thereof Download PDFInfo
- Publication number
- US20130328202A1 US20130328202A1 US13/490,472 US201213490472A US2013328202A1 US 20130328202 A1 US20130328202 A1 US 20130328202A1 US 201213490472 A US201213490472 A US 201213490472A US 2013328202 A1 US2013328202 A1 US 2013328202A1
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- layer
- imd
- tsv
- semiconductor substrate
- cap layer
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/481—Internal lead connections, e.g. via connections, feedthrough structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
- H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
- H01L23/5226—Via connections in a multilevel interconnection structure
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
- H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
- H01L23/532—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body characterised by the materials
- H01L23/53204—Conductive materials
- H01L23/53209—Conductive materials based on metals, e.g. alloys, metal silicides
- H01L23/53228—Conductive materials based on metals, e.g. alloys, metal silicides the principal metal being copper
- H01L23/53238—Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
- H01L21/768—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
- H01L21/76838—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the conductors
- H01L21/76841—Barrier, adhesion or liner layers
- H01L21/76843—Barrier, adhesion or liner layers formed in openings in a dielectric
- H01L21/76849—Barrier, adhesion or liner layers formed in openings in a dielectric the layer being positioned on top of the main fill metal
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
Definitions
- the present invention relates generally to semiconductor technology, and more particularly to a through-silicon via (TSV) for connection of stacked chips and a method for forming the same.
- TSV through-silicon via
- stack package is a vertical stand or pile of at least two chips or packages, one atop the other.
- a stack package provides advantages not only through an increase in memory capacity but also in view of a mounting density and mounting area utilization efficiency.
- a through-silicon via (TSV) has been disclosed in the art.
- the stack package using a TSV has a structure in which the TSV is formed in a chip so that chips are physically and electrically connected with each other through the TSV.
- TSV Through silicon via
- a vertical hole is defined through a predetermined portion of each chip at a wafer level.
- An insulation layer is formed on the surface of the vertical hole.
- a metal is filled into the vertical hole through an electroplating process to form a TSV. Then, the TSV is exposed through back-grinding of the backside of a wafer.
- At least two chips can be vertically stacked, one atop the other, on one of the substrates using one or more of the TSV.
- the upper surface of the substrate including the stacked chips is molded, and solder balls are mounted on the lower surface of the substrate.
- the present invention provides a through silicon via (TSV) structure including a semiconductor substrate; a first inter-metal dielectric (IMD) layer on the semiconductor substrate; a cap layer overlying the IMD layer; a conductive layer extending through the cap layer, the first IMD layer and into the semiconductor substrate; a tungsten film capping a top surface of the conductive layer; a second IMD layer overlying the cap layer and covering the tungsten film; and an interconnect feature in the second IMD layer.
- TSV through silicon via
- FIGS. 1-4 are schematic, cross-sectional diagrams showing an exemplary method for fabricating a through silicon via (TSV) in accordance with one embodiment of this invention.
- TSV through silicon via
- FIGS. 1-4 are schematic, cross-sectional diagrams showing an exemplary method for fabricating a through silicon via (TSV) in accordance with one embodiment of this invention.
- a semiconductor substrate 10 having a front side 10 a and a back side 10 b is provided. It is to be understood that the semiconductor substrate 10 may be a base layer in other cases.
- An inter-metal dielectric (IMD) layer 12 may be formed on the front side 10 a of the semiconductor substrate 10 .
- a tungsten plug 14 or tungsten local interconnect may be formed in the IMD layer 12 .
- a cap layer 16 such as a silicon nitride layer may be formed on the IMD layer 12 .
- a TSV trench 18 is then etched into the cap layer 16 , the IMD layer 12 and the semiconductor substrate 10 .
- a barrier or seed layer (not explicitly shown) may be formed inside the TSV trench 18 .
- a conductive layer 20 such as copper may be deposited into the TSV trench 18 by using, for example, electroplating or the like. Thereafter, a chemical mechanical polishing (CMP) may be performed to remove the excess conductive layer 20 outside the TSV trench 18 . At this point, a top surface of the conductive layer 20 is flush with a top surface of the cap layer 16 that may act as a polish stop during CMP.
- CMP chemical mechanical polishing
- a selective tungsten chemical vapor deposition (WCVD) process is then performed to selectively deposit a tungsten film 22 on the exposed top surface of the conductive layer 20 .
- the semiconductor substrate 10 may be subjected to a degassing treatment (degassing condition: 250° C.), the degassed substrate is then introduced into a chamber for the pre-treatment, and then the substrate may be heated to a pre-treating temperature of 250° C. Subsequently, 50 sccm of N2 gas and 100 sccm of H2 gas may be simultaneously introduced into the chamber and a discharge may be induced with an RF plasma generator to subject the substrate surface to a pre-treatment for 30 seconds.
- a degassing treatment degassing condition: 250° C.
- 50 sccm of N2 gas and 100 sccm of H2 gas may be simultaneously introduced into the chamber and a discharge may be induced with an RF plasma generator to subject the substrate surface to a pre-treatment for 30 seconds.
- the substrate is moved to a chamber for carrying out the selective WCVD.
- the substrate may be heated up to 250° C., and 10 sccm of WF6 and 5 sccm of SiH4 may be introduced into the chamber to thus form the tungsten film 22 on the copper surface.
- a CVD process may be carried out to deposit an IMD layer 30 such as a silicon oxide layer.
- the IMD layer 30 covers the cap layer 16 and the tungsten film 22 .
- a lithographic process and a dry etching process are performed to create interconnection structures 30 a and 30 b in the IMD layer 30 .
- the interconnection structures 30 a and 30 b may be damascened trenches.
- the interconnection structures 30 a extend the entire thickness of the IMD layer 30 and expose a portion of the tungsten film 22 .
- the interconnection structure 30 b extends through the IMD layer 30 and the cap layer 16 and exposes the top surface of the tungsten plug 14 .
- a portion of the IMD layer 12 may be exposed too.
- the substrate is then subjected to a pre-clean process for removing tungsten oxide from the exposed tungsten surfaces. For example, the exposed tungsten surfaces may be bombarded by argon.
- a copper damascene process is performed to fill the interconnection structures 30 a and 30 b with copper interconnect features 32 and 34 including but not limited to a barrier layer and a copper layer. It is advantageous to use the invention because during the pre-clean process prior to the formation of the copper interconnect features 32 and 34 , only the tungsten surfaces are exposed and therefore the damage to TSV due to argon bombardment can be avoided. The electrical performance of copper interconnect features 32 and 34 is improved.
- the structural features as set forth in FIG. 4 may include: (1) the tungsten film 22 that is selectively formed on the top surface of the conductive layer or copper layer 20 ; and (2) the copper interconnect features 32 that are in direct contact with the tungsten film 22 .
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- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
Abstract
A through silicon via (TSV) structure including a semiconductor substrate; a first inter-metal dielectric (IMD) layer on the semiconductor substrate; a cap layer overlying the IMD layer; a conductive layer extending through the cap layer, the first IMD layer and into the semiconductor substrate; a tungsten film capping a top surface of the conductive layer; a second IMD layer overlying the cap layer and covering the tungsten film; and an interconnect feature in the second IMD layer.
Description
- 1. Field of the Invention
- The present invention relates generally to semiconductor technology, and more particularly to a through-silicon via (TSV) for connection of stacked chips and a method for forming the same.
- 2. Description of the Prior Art
- Packaging technology for an integrated circuit has continuously been developed to meet the demand toward miniaturization and mounting reliability. As known in the art, stack package is a vertical stand or pile of at least two chips or packages, one atop the other. By using a stack, in the case of a memory device for example, it is possible to produce a product having a memory capacity which is two times greater than that obtainable through semiconductor integration processes.
- A stack package provides advantages not only through an increase in memory capacity but also in view of a mounting density and mounting area utilization efficiency. As an example of a stack package, a through-silicon via (TSV) has been disclosed in the art. The stack package using a TSV has a structure in which the TSV is formed in a chip so that chips are physically and electrically connected with each other through the TSV.
- Through silicon via (TSV) is typically fabricated to provide the through-via filled with a conducting material that pass completely through the silicon layer to contact and connect with the other TSVs and conductors of the bonded layers. For example, a vertical hole is defined through a predetermined portion of each chip at a wafer level. An insulation layer is formed on the surface of the vertical hole. With a seed metal layer formed on the insulation layer, a metal is filled into the vertical hole through an electroplating process to form a TSV. Then, the TSV is exposed through back-grinding of the backside of a wafer. After the wafer is sawed and is separated into individual chips, at least two chips can be vertically stacked, one atop the other, on one of the substrates using one or more of the TSV. Thereupon, the upper surface of the substrate including the stacked chips is molded, and solder balls are mounted on the lower surface of the substrate.
- In one aspect, the present invention provides a through silicon via (TSV) structure including a semiconductor substrate; a first inter-metal dielectric (IMD) layer on the semiconductor substrate; a cap layer overlying the IMD layer; a conductive layer extending through the cap layer, the first IMD layer and into the semiconductor substrate; a tungsten film capping a top surface of the conductive layer; a second IMD layer overlying the cap layer and covering the tungsten film; and an interconnect feature in the second IMD layer.
- These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
- The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate some of the embodiments and, together with the description, serve to explain their principles. In the drawings:
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FIGS. 1-4 are schematic, cross-sectional diagrams showing an exemplary method for fabricating a through silicon via (TSV) in accordance with one embodiment of this invention. - It should be noted that all the figures are diagrammatic. Relative dimensions and proportions of parts of the drawings have been shown exaggerated or reduced in size, for the sake of clarity and convenience in the drawings. The same reference signs are generally used to refer to corresponding or similar features in modified and different embodiments.
- In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific examples in which the embodiments may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice them, and it is to be understood that other embodiments may be utilized and that structural, logical and electrical changes may be made without departing from the described embodiments. The following detailed description is, therefore, not to be taken in a limiting sense, and the included embodiments are defined by the appended claims.
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FIGS. 1-4 are schematic, cross-sectional diagrams showing an exemplary method for fabricating a through silicon via (TSV) in accordance with one embodiment of this invention. As shown inFIG. 1 , asemiconductor substrate 10 having afront side 10 a and aback side 10 b is provided. It is to be understood that thesemiconductor substrate 10 may be a base layer in other cases. An inter-metal dielectric (IMD)layer 12 may be formed on thefront side 10 a of thesemiconductor substrate 10. Atungsten plug 14 or tungsten local interconnect may be formed in theIMD layer 12. Acap layer 16 such as a silicon nitride layer may be formed on theIMD layer 12. ATSV trench 18 is then etched into thecap layer 16, theIMD layer 12 and thesemiconductor substrate 10. A barrier or seed layer (not explicitly shown) may be formed inside the TSVtrench 18. Aconductive layer 20 such as copper may be deposited into the TSVtrench 18 by using, for example, electroplating or the like. Thereafter, a chemical mechanical polishing (CMP) may be performed to remove the excessconductive layer 20 outside the TSVtrench 18. At this point, a top surface of theconductive layer 20 is flush with a top surface of thecap layer 16 that may act as a polish stop during CMP. - As shown in
FIG. 2 , a selective tungsten chemical vapor deposition (WCVD) process is then performed to selectively deposit atungsten film 22 on the exposed top surface of theconductive layer 20. For example, thesemiconductor substrate 10 may be subjected to a degassing treatment (degassing condition: 250° C.), the degassed substrate is then introduced into a chamber for the pre-treatment, and then the substrate may be heated to a pre-treating temperature of 250° C. Subsequently, 50 sccm of N2 gas and 100 sccm of H2 gas may be simultaneously introduced into the chamber and a discharge may be induced with an RF plasma generator to subject the substrate surface to a pre-treatment for 30 seconds. After the pre-treatment, the substrate is moved to a chamber for carrying out the selective WCVD. For example, the substrate may be heated up to 250° C., and 10 sccm of WF6 and 5 sccm of SiH4 may be introduced into the chamber to thus form thetungsten film 22 on the copper surface. - Subsequently, as shown in
FIG. 3 , a CVD process may be carried out to deposit anIMD layer 30 such as a silicon oxide layer. The IMDlayer 30 covers thecap layer 16 and thetungsten film 22. A lithographic process and a dry etching process are performed to createinterconnection structures IMD layer 30. Theinterconnection structures interconnection structures 30 a extend the entire thickness of theIMD layer 30 and expose a portion of thetungsten film 22. Theinterconnection structure 30 b extends through theIMD layer 30 and thecap layer 16 and exposes the top surface of thetungsten plug 14. A portion of theIMD layer 12 may be exposed too. The substrate is then subjected to a pre-clean process for removing tungsten oxide from the exposed tungsten surfaces. For example, the exposed tungsten surfaces may be bombarded by argon. - As shown in
FIG. 4 , after the formation of theinterconnection recess structures interconnection structures copper interconnect features FIG. 4 may include: (1) thetungsten film 22 that is selectively formed on the top surface of the conductive layer orcopper layer 20; and (2) thecopper interconnect features 32 that are in direct contact with thetungsten film 22. - Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
Claims (6)
1. A semiconductor structure, comprising:
a semiconductor substrate;
a first inter-metal dielectric (IMD) layer on the semiconductor substrate;
a tungsten plug embedded in the IMD layer;
a cap layer overlying the IMD layer and capping the tungsten plug;
a through silicon via (TSV) comprising: a conductive layer penetrating through the cap layer, the first IMD layer and the semiconductor substrate, wherein the conductive layer has a top surface that is flush with a top surface of the cap layer; and a tungsten film capping entire said top surface of the conductive layer;
a second IMD layer overlying the cap layer and covering the tungsten film;
a first interconnect feature penetrating through the second IMD layer to electrically connect with the TSV; and
a second interconnect feature penetrating through the second IMD layer and the cap layer to electrically connect with the tungsten plug.
2. The semiconductor structure according to claim 1 wherein the cap layer comprises silicon nitride.
3. The semiconductor structure according to claim 1 wherein the first or second interconnect feature comprises copper damascene structure.
4. The semiconductor structure according to claim 1 wherein the first interconnect feature is in direct contact with the tungsten film.
5. The semiconductor structure according to claim 1 wherein the first IMD layer comprises silicon oxide.
6. The semiconductor structure according to claim 1 wherein the second IMD layer comprises silicon oxide.
Priority Applications (3)
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US13/490,472 US8587131B1 (en) | 2012-06-07 | 2012-06-07 | Through-silicon via and fabrication method thereof |
TW101126946A TWI456719B (en) | 2012-06-07 | 2012-07-26 | Through-silicon via and fabrication method thereof |
CN201210323190.1A CN103489840B (en) | 2012-06-07 | 2012-09-04 | Silicon through hole and preparation method thereof |
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US13/490,472 US8587131B1 (en) | 2012-06-07 | 2012-06-07 | Through-silicon via and fabrication method thereof |
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US8587131B1 US8587131B1 (en) | 2013-11-19 |
US20130328202A1 true US20130328202A1 (en) | 2013-12-12 |
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JP5353109B2 (en) * | 2008-08-15 | 2013-11-27 | 富士通セミコンダクター株式会社 | Manufacturing method of semiconductor device |
US9514986B2 (en) * | 2013-08-28 | 2016-12-06 | Taiwan Semiconductor Manufacturing Company, Ltd. | Device with capped through-substrate via structure |
CN105097766B (en) * | 2014-05-13 | 2017-09-15 | 旺宏电子股份有限公司 | The semiconductor structure and its manufacture method of contact structures with different form ratios |
TWI553803B (en) * | 2014-05-15 | 2016-10-11 | 旺宏電子股份有限公司 | Semiconductor structure having contact structures with different aspect ratios and manufacturing method of the semiconductor structure |
CN105895579B (en) * | 2016-06-08 | 2017-12-05 | 无锡微奥科技有限公司 | A kind of processing method of the TSV disks based on SOI substrate |
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US6258713B1 (en) * | 1999-12-03 | 2001-07-10 | United Microelectronics Corp. | Method for forming dual damascene structure |
JP2003068848A (en) * | 2001-08-29 | 2003-03-07 | Fujitsu Ltd | Semiconductor device and its manufacturing method |
US7799678B2 (en) * | 2008-01-30 | 2010-09-21 | Freescale Semiconductor, Inc. | Method for forming a through silicon via layout |
KR101458958B1 (en) * | 2008-06-10 | 2014-11-13 | 삼성전자주식회사 | Semiconductor chip, semiconductor package, and method of fabricating the semiconductor chip |
JP2010010324A (en) * | 2008-06-26 | 2010-01-14 | Toshiba Corp | Semiconductor device and method of manufacturing the same |
US8552563B2 (en) * | 2009-04-07 | 2013-10-08 | Taiwan Semiconductor Manufacturing Company, Ltd. | Three-dimensional semiconductor architecture |
JP2011228419A (en) * | 2010-04-19 | 2011-11-10 | Renesas Electronics Corp | Semiconductor integrated circuit device and method for manufacturing the same |
KR20120000748A (en) * | 2010-06-28 | 2012-01-04 | 삼성전자주식회사 | Semiconductor device and method of manufacturing the same |
US8912658B2 (en) * | 2010-10-29 | 2014-12-16 | International Business Machines Corporation | Interconnect structure with enhanced reliability |
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2012
- 2012-06-07 US US13/490,472 patent/US8587131B1/en active Active
- 2012-07-26 TW TW101126946A patent/TWI456719B/en active
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CN103489840B (en) | 2016-08-17 |
TWI456719B (en) | 2014-10-11 |
CN103489840A (en) | 2014-01-01 |
TW201351587A (en) | 2013-12-16 |
US8587131B1 (en) | 2013-11-19 |
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