SYSTEM AND METHOD FOR MASKLESS THIN FILM BATTERY FABRICATION
A method for masklessly fabricating a thin film battery, including securing a substrate to a substrate carrier of a first deposition chamber with a first clamping ring having an aperture, performing a first deposition on the substrate to form a first TFB layer, the aperture of the first clamping ring defining a footprint of the first layer, wherein areas of the substrate covered by the first clamping ring are excluded from the first blanket deposition, securing the substrate to a substrate carrier of a second deposition chamber with a second clamping ring having an aperture, and performing a second deposition on the substrate to form a second TFB layer over the first layer, the aperture of the second clamping ring defining a footprint of the second layer, wherein areas of the substrate and the first layer covered by the second clamping ring are excluded from the second blanket deposition.
This application claims priority to U.S. provisional patent application No. 62/322,415, filed Apr. 14, 2016, entitled “Volume Change Accommodating TFE Materials” and incorporated by reference herein in its entirety.
FIELDThe present embodiments relate generally to the fabrication of thin film batteries, and more particularly to the fabrication of thin film batteries using maskless deposition techniques.
BACKGROUNDSolid state Thin Film Batteries (TFB) are known to exhibit several advantages over conventional battery technologies. These advantages include superior form factors, cycle life, power capability, and safety. Still, there is a need for cost effective and high-volume manufacturing (HVM) compatible fabrication technologies to enable broad market applicability of TFBs.
An embodiment of a TFB may include a plurality of layers disposed in a vertically stacked arrangement, such layers including a positive electrode layer (e.g., a cathode) and a negative electrode layer (e.g., an anode) separated by a solid state electrolyte. These layers are commonly formed by successive deposition of the layers on a substrate using a deposition chamber. The surface area or “footprint” of a deposited layer is defined using a mask positioned above a substrate during deposition. Since one or more layers of a TFB may have a unique footprint relative to the other layers, a plurality of masks are normally necessary for fabricating a TFB.
A shortcoming associated with masked deposition techniques for fabricating TFBs is susceptibility to electrical shorting between the positive electrode and negative electrode layers during deposition, possibly leading to irreversible device failure. Additionally, implementing numerous masks during device fabrication decreases throughput and increases manufacturing costs.
Accordingly, a need remains in the art for fabrication processes and technologies for TFBs compatible with cost effective and HVM to enhance market applicability of TFBs.
With respect to these and other considerations the present disclosure is provided.
BRIEF SUMMARYAn exemplary embodiment of a system for maskless TFB fabrication in accordance with the present disclosure may include a deposition chamber adapted to deposit a first layer of the TFB on a substrate, the first deposition chamber having a first clamping ring adapted to secure the substrate to a first substrate carrier. The first clamping ring may have an aperture with a size and shape defining a footprint of the first layer, and a second deposition chamber adapted to deposit a second layer of the TFB over the first layer. The second deposition chamber may have a second clamping ring adapted to secure the substrate to a second substrate carrier, the second clamping ring having an aperture with a size and shape defining a footprint of the second layer.
An exemplary embodiment of a method for maskless TFB fabrication in accordance with the present disclosure may include securing a substrate to a substrate carrier of a first deposition chamber with a first clamping ring having an aperture. The method may further include performing a first blanket deposition on the substrate to form a first layer of the TFB, wherein the aperture of the first clamping ring defines a footprint of the first layer. Areas of the substrate covered by the first clamping ring are excluded from the first blanket deposition. The method may further include securing the substrate to a substrate carrier of a second deposition chamber with a second clamping ring having an aperture, and performing a second blanket deposition on the substrate to form a second layer of the TFB over the first layer. The aperture of the second clamping ring defines a footprint of the second layer, wherein areas of the substrate and the first layer covered by the second clamping ring are excluded from the second blanket deposition.
Another exemplary embodiment of a method for maskless TFB fabrication in accordance with the present disclosure may include securing a substrate to a substrate carrier of a first deposition chamber with a first clamping ring having an aperture. The method may further include performing a first blanket deposition on the substrate to form a positive electrode layer of the TFB, wherein the aperture of the first clamping ring defines a footprint of the positive electrode layer. Areas of the substrate covered by the first clamping ring are excluded from the first blanket deposition. The method may further include securing the substrate to a substrate carrier of a second deposition chamber with a second clamping ring having an aperture, and performing a second blanket deposition on the substrate to form a solid state electrolyte layer of the TFB over the positive electrode layer. The aperture of the second clamping ring defines a footprint of the solid state electrolyte layer, wherein areas of the substrate and the first layer covered by the second clamping ring are excluded from the second blanket deposition. The method may further include securing the substrate to a substrate carrier of a third deposition chamber with a third clamping ring having an aperture, and performing a third blanket deposition on the substrate to form a negative electrode layer of the TFB over the solid state electrolyte layer. The aperture of the third clamping ring defines a footprint of the negative electrode layer, wherein areas of the substrate, the first layer, and the second layer covered by the third clamping ring are excluded from the third blanket deposition.
The present embodiments will now be described more fully hereinafter with reference to the accompanying drawings, where some embodiments are shown. The subject matter of the present disclosure may be embodied in many different forms and is not to be construed as limited to the embodiments set forth herein. In the drawings, like numbers refer to like elements throughout.
The present disclosure relates to systems and methods for fabricating thin film batteries (TFBs). Particularly, the disclosed systems and methods are compatible with high throughput production and high volume manufacturing methodologies. As will be appreciated, high throughput production of TFBs includes certain challenges. For example, sputter deposition of layers of a TFB can result in electrical shorting between positive electrode and negative electrode layers of a TFB, possibly leading to irreversible device failure. Such issues can be exacerbated as higher throughput is pursued to achieve the goal of reducing the overall cost of manufacturing while maintaining the basic requirements for layers, interfaces, device stability/stress, and cell performance in TFBs. The disclosed systems and methods address and overcome these issues.
In general, the disclosed systems and methods utilize substrate clamping rings or edge exclusion rings (hereinafter collectively referred to as “clamping rings”) of different sizes (e.g., different interior areas) for achieving concentric edge exclusion regions on a substrate to selectively vary the surface area of sequentially deposited layers of a TFB. For example, as will be described in greater detail below, a substrate may be secured to a substrate carrier (e.g., a pedestal) in a deposition chamber using a first clamping ring. The first clamping ring may be separate from or integral with the substrate carrier and may have a circular, rectangular, or other shape. A blanket deposition may then be performed on the substrate to create a first layer (e.g., a positive electrode) of a TFB, with an interior area of the first clamping ring defining the surface area of “footprint” of the first layer. The first clamping ring may then be removed and the substrate may again be clamped to a substrate carrier. The substrate carrier may be the same substrate carrier used in the first deposition or a different substrate carrier in the same or a different deposition chamber, using a second clamping ring having an interior area larger than the interior area of the first clamping ring. A blanket deposition may then be performed on the substrate to create a second layer (e.g., a solid state electrolyte) of the TFB, with an interior area of the second clamping ring defining the footprint of the second layer.
Since the interior area of the second clamping ring is larger than the interior area of the first clamping ring, the second layer of the TFB may overlay, and may entirely overlap the edges of, the underlying first layer. The second clamping ring may then be removed and the substrate may again be clamped to a substrate carrier. The substrate carrier may be the same substrate carrier used in the first and/or second deposition or a different substrate carrier in the same or a different deposition chamber, using a third clamping ring having an interior area smaller than the interior area of the second clamping ring. A blanket deposition may then be performed on the substrate to create a third layer (e.g., a negative electrode) on top of the second layer. Thus, physical separation between the first and third layers of the TFB is ensured by the blanket deposition of the intermediate second layer, and electrical shorting between the first and third layers (e.g., the positive electrode and the negative electrode) is prevented. The TFB may include various other layers as further described below.
As will be appreciated, a variety of different TFB architectures can be fabricated using the processes and tooling arrangements described herein.
The positive electrode layer 16 may be LiCoO2 or a similar material. The solid state electrolyte 18 may be a lithium phosphorus oxynitride (LiPON) or similar material. The negative electrode layer 20 may include lithium or a lithium-containing material. In one non-limiting embodiment, the stack of layers 12 may have a thickness of 15 microns.
Referring to
At a block 100 of the exemplary fabrication method, and as depicted in
At block 105 of the exemplary fabrication method, a first deposition may be performed on the substrate 40 to form a first layer 48 (see
At block 110 of the exemplary fabrication method, the first clamping ring 44 may be removed from the substrate 40, releasing the substrate 40 from the substrate carrier 42. At block 115 of the method, the substrate 40 may be clamped to a substrate carrier 52 by a second clamping ring 54 as shown in
The second clamping ring 54 may define a circular aperture 56 having a diameter d2. In one non-limiting example, the diameter d2 may be larger than the diameter d1 of the aperture 46 of the first clamping ring 44 (e.g., given the same outer diameter, the second clamping ring 54 may be radially thinner than the first clamping ring 44), and may be in a range of 100 millimeters to 450 millimeters. Thus, when the substrate 40 is clamped to the substrate carrier 52, an annular gap g may be defined radially intermediate the second clamping ring 54 and a radial edge of the first layer 48 on the substrate 40. In various alternative embodiments, the second clamping ring 54 and/or the aperture 56 may have a variety of different shapes, such as rectangular, oval, triangular, irregular, etc. as may be appropriate for a particular application. The size and shape of the aperture 56 may correspond to a predetermined footprint for a second layer of a TFB to be deposited on the substrate 40. In some embodiments, the size and shape of the aperture 56 may be the same as the size and shape of the aperture 46 of the first clamping ring 44.
At block 120 of the exemplary fabrication method, a second deposition may be performed on the substrate 40 to form a second layer 58 (see
At block 125 of the exemplary fabrication method, the second clamping ring 54 may be removed from the substrate 40, releasing the substrate 40 from the substrate carrier 52. At block 130 of the method, the substrate 40 may be clamped to a substrate carrier 62 by a third clamping ring 64 as shown in
The third clamping ring 64 may define a circular aperture 66 having a diameter d3. In one non-limiting example, the diameter d3 may be smaller than the diameter d2 of the aperture 56 of the second clamping ring 54 (e.g., given the same outer diameter, the third clamping ring 64 may be radially thicker than the second clamping ring 54), and may be in a range of 100 millimeters to 450 millimeters. Thus, when the substrate 40 is clamped to the substrate carrier 62, the third clamping ring 64 may engage an upper surface of the second layer 58. In various alternative embodiments, the third clamping ring 64 and/or the aperture 66 may have a variety of different shapes, such as rectangular, oval, triangular, irregular, etc. as may be appropriate for a particular application. The size and shape of the aperture 66 may correspond to a predetermined footprint for a third layer of a TFB to be deposited on the substrate 40. In some embodiments, the size and shape of the aperture 66 may be the same as the size and shape of the aperture 56 of the second clamping ring 54 and/or the first clamping ring 44.
At block 135 of the exemplary fabrication method, a third deposition may be performed on the substrate 40 to form a third layer 68 (see
Referring to
There are multiple advantages provided by the present embodiments. A first advantage includes facilitating the fabrication of successive, stacked TFB layers with varying footprints via maskless, blanket deposition, leading to reduced manufacturing costs and improved throughput relative to fabrication systems and methods requiring the implementation of masks during deposition. Another advantage includes enhanced throughput if the various TFB layers described above are deposited using respective, separate deposition chambers with respective clamping rings adapted for defining the respective layers. In this manner the configuration of a particular deposition chamber need not be changed in the course of fabrication. Furthermore, a deposition chamber may perform deposition of one of the TFB layers on a first substrate while another deposition chamber simultaneous performs deposition of another one of the TFB layers on another substrate.
The present disclosure is not to be limited in scope by the specific embodiments described herein. Indeed, other various embodiments of, and modifications to, the present disclosure, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings. Thus, such other embodiments and modifications are in the tended to fall within the scope of the present disclosure. Furthermore, the present disclosure has been described herein in the context of a particular implementation in a particular environment for a particular purpose, while those of ordinary skill in the art will recognize the usefulness is not limited thereto and the present disclosure may be beneficially implemented in any number of environments for any number of purposes. Thus, the claims set forth below are to be construed in view of the full breadth and spirit of the present disclosure as described herein.
Claims
1. A system for maskless thin film battery (TFB) fabrication, comprising:
- a first deposition chamber adapted to deposit a first layer of the TFB on a substrate, the first deposition chamber having a first clamping ring adapted to secure the substrate to a first substrate carrier, the first clamping ring having an aperture with a size and shape defining a footprint of the first layer; and
- a second deposition chamber adapted to deposit a second layer of the TFB over the first layer, the second deposition chamber having a second clamping ring adapted to secure the substrate to a second substrate carrier, the second clamping ring having an aperture with a size and shape defining a footprint of the second layer.
2. The system of claim 1, wherein the first deposition chamber and the second deposition chamber are the same deposition chamber.
3. The system of claim 1, wherein the first substrate carrier and the second substrate carrier are the same substrate carrier.
4. The system of claim 1, wherein the aperture of the first clamping ring has a first size and the aperture of the second clamping ring has a second size, wherein the second size is larger than the first size.
5. The system of claim 4, wherein a position of the first clamping ring relative to the substrate is concentric with a position of the second clamping ring relative to the substrate.
6. The system of claim 1, wherein the footprint defined by the aperture of the second clamping ring is adapted to entirely cover, and overlap edges of, the footprint defined by the aperture of the first clamping ring.
7. The system of claim 1, further comprising a third deposition chamber adapted to deposit a third layer of the TFB over the second layer, the third deposition chamber having a third clamping ring adapted to secure the substrate to a third substrate carrier, the third clamping ring having an aperture with a size and shape defining a footprint of the third layer.
8. The system of claim 7, wherein the first deposition chamber is adapted to perform a blanket deposition of a positive electrode layer, the second deposition chamber is configured to perform a blanket deposition of a solid state electrolyte layer, and the third deposition chamber is configured to perform a blanket deposition of a negative electrode layer.
9. The system of claim 7, wherein the aperture of the first clamping ring has a first size, the aperture of the second clamping ring has a second size, and the aperture of the third clamping ring has a third size, wherein the second size is larger than the first size and the third size is smaller than the second size.
10. A method for masklessly fabricating a thin film battery (TFB), comprising:
- securing a substrate to a substrate carrier of a first deposition chamber with a first clamping ring having an aperture;
- performing a first blanket deposition on the substrate to form a first layer of the TFB, wherein the aperture of the first clamping ring defines a footprint of the first layer, and wherein areas of the substrate covered by the first clamping ring are excluded from the first blanket deposition;
- securing the substrate to a substrate carrier of a second deposition chamber with a second clamping ring having an aperture; and
- performing a second blanket deposition on the substrate to form a second layer of the TFB over the first layer, wherein the aperture of the second clamping ring defines a footprint of the second layer, and wherein areas of the substrate and the first layer covered by the second clamping ring are excluded from the second blanket deposition.
11. The method of claim 10, wherein the first deposition chamber and the second deposition chamber are different deposition chambers.
12. The method of claim 10, wherein the first deposition chamber and the second deposition chamber are the same deposition chamber.
13. The method of claim 10, wherein the substrate carrier of the first deposition chamber and the substrate carrier of the second deposition chamber are the same substrate carrier.
14. The method of claim 10, wherein the aperture of the first clamping ring has a first size and the aperture of the second clamping ring has a second size, wherein the second size is larger than the first size.
15. The method of claim 10, wherein a position of the first clamping ring relative to the substrate is concentric with a position of the second clamping ring relative to the substrate.
16. The method of claim 10, wherein the second layer entirely covers, and overlaps edges of, the first layer.
17. The method of claim 10, further comprising securing the substrate to a substrate carrier of a third deposition chamber with a third clamping ring having an aperture; and
- performing a third blanket deposition on the substrate to form a third layer of the TFB over the second layer, wherein the aperture of the third clamping ring defines a footprint of the third layer, and wherein areas of the substrate, the first layer, and the second layer covered by the third clamping ring are excluded from the third blanket deposition.
18. The method of claim 17, wherein the first layer is a positive electrode layer, the second layer is a solid state electrolyte layer, and the third layer is a negative electrode layer.
19. The method of claim 17, wherein the aperture of the first clamping ring has a first size, the aperture of the second clamping ring has a second size, and the aperture of the third clamping ring has a third size, wherein the second size is larger than the first size and the third size is smaller than the second size.
20. A method for masklessly fabricating a thin film battery (TFB), comprising:
- securing a substrate to a substrate carrier of a first deposition chamber with a first clamping ring having an aperture;
- performing a first blanket deposition on the substrate to form a positive electrode layer of the TFB, wherein the aperture of the first clamping ring defines a footprint of the positive electrode layer, and wherein areas of the substrate covered by the first clamping ring are excluded from the first blanket deposition;
- securing the substrate to a substrate carrier of a second deposition chamber with a second clamping ring having an aperture;
- performing a second blanket deposition on the substrate to form a solid state electrolyte layer of the TFB over the positive electrode layer, wherein the aperture of the second clamping ring defines a footprint of the solid state electrolyte layer, and wherein areas of the substrate and the positive electrode layer covered by the second clamping ring are excluded from the second blanket deposition;
- securing the substrate to a substrate carrier of a third deposition chamber with a third clamping ring having an aperture; and
- performing a third blanket deposition on the substrate to form a negative electrode layer of the TFB over the solid state electrolyte layer, wherein the aperture of the third clamping ring defines a footprint of the negative electrode layer, and wherein areas of the substrate, positive electrode first layer, and the solid state electrolyte layer covered by the third clamping ring are excluded from the third blanket deposition.
Type: Application
Filed: Oct 31, 2016
Publication Date: Oct 19, 2017
Inventors: Dimitrios Argyris (Los Altos, CA), Byung-Sung Kwak (Portland, OR), Lizhong Sun (San Jose, CA), Giback Park (San Jose, CA)
Application Number: 15/339,168