Layer structure of solid-state battery and manufacturing method thereof

Abstract

To provide a layer structure of a solid-state battery which achieves improved battery charge capacity, and a manufacturing method thereof.SOLUTION: A layer structure (100) of a solid state battery comprises an anode current collector metal layer (110), an anode layer (120) disposed on the anode current collector metal layer, a solid electrolyte layer (140) laterally disposed on the anode layer, a cathode layer (150) disposed on the solid electrolyte layer, a cathode current collector metal layer (160), and a plurality of nanowire structures (130) comprising silicon and / or gallium nitride. The nanowire structures (130) are disposed on the anode layer (120), and the nanowire structures (130) is laterally and vertically encased by the solid electrolyte layer (140). The anode layer comprises silicon and a plurality of metal vias (224) connecting the plurality of nanowire structures to the anode current collector metal layer (110). The method of manufacturing a layer structure of a solid-state battery is also provided.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a layer structure of a solid-state battery and a method for producing the same. [Background technology]

[0002] Lithium-ion battery technology with its high charge capacity level and rechargeability has played a key role in advancing the storage of electrical energy and enabling mobile electronic devices such as portable computers and phones. Lithium-ion batteries have also been important for the resurgence of electric vehicles. However, so far, conventional lithium-ion battery technology has its own range of problems. To achieve battery improvements essentially across the board, designs of battery devices featuring solid electrolytes, as opposed to conventional liquid electrolytes, have gained prominence. Batteries with solid electrolytes are commonly referred to as solid-state batteries. Solid electrolytes, for example, reduce the risk of battery fire while requiring new battery designs in terms of morphology and materials to realize the full potential of improved performance compared to liquid electrolyte batteries. In particular, improving the charge capacity of solid-state batteries, defined as the ratio of storable charge to the weight of the battery, has not yet been adequately addressed in the prior art. In addition, material-dependent volume expansion is another problem faced by prior art solid-state batteries. Thus, there is a need for improvements in the field. Summary of the Invention [Problem to be solved by the invention]

[0003] It is an object of the present invention to provide a layered structure for a solid-state battery that alleviates at least some of the aforementioned problems and allows for improved battery charge capacity, as well as a method for manufacturing the structure. [Means for solving the problem]

[0004] According to a first aspect of the present invention, there is provided a layer structure of a solid-state battery, comprising: an anode current collector metal layer; an anode layer disposed on the anode current collector metal layer; a solid electrolyte layer disposed laterally on the anode layer; a cathode layer disposed on the solid electrolyte layer; a cathode current collector metal layer; the anode layer comprises silicon; A layer structure for a solid-state battery is provided.

[0005] The term "disposed on" may refer to having layers or structures disposed on top of one another in the vertical direction of the layer structure or stack. The vertical direction may be substantially perpendicular and perpendicular to the surface of the layer or layers within the layer structure. The term "comprising" may refer throughout this disclosure to layers and structures that at least partially comprise a particular material. This term does not exclude a layer or structure from containing impurities of other materials, nor does it exclude a layer or structure that consists essentially of the material that it is made up of.

[0006] Such a structure may alleviate some of the problems of the prior art. Silicon anodes may be advantageous, for example, for lithium-ion based batteries in increasing the charge capacity. This is because silicon atoms, which are well alloyed to form composite anode materials, are better at bonding with and thus holding more lithium atoms than the carbon atoms of conventional graphite anodes. Battery charge capacity may be recorded in units of ampere-hours or coulombs. Furthermore, the use of silicon anodes may simplify the manufacture of the layered structure of the battery and increase production, since advanced techniques and methods commonly used in microelectronics fabrication may be utilized. As such, solid-state batteries may be effectively miniaturized. Silicon anodes may be based on single crystal substrates. As such, the layered structure of the solid-state battery may be more integrally formed with silicon-based microelectronics. Thus, electronic circuits and devices integrated with solid-state batteries may be both enabled and miniaturized.

[0007] The anode layer may include gallium nitride.

[0008] Utilizing gallium nitride in an anode layer, for example as a thin top layer of an anode layer that otherwise contains primarily silicon, may alleviate problems in the prior art. The charge capacity in a solid-state battery with gallium nitride anode material may be ∼2.5 times greater than a solid-state battery with a conventional graphite anode. The diffusion barrier for lithium ion diffusion with a gallium nitride anode may also be lower compared to the same barrier for a graphite anode. This may be advantageous for rapid battery charging.

[0009] The layer structure of the solid-state battery may further include a plurality of nanowire structures, the nanowire structures being disposed on the anode layer, and the nanowire structures being laterally and vertically enveloped by the solid-state electrolyte layer.

[0010] The term "nanowire structure", also simply referred to as nanostructure, may refer to an elongated structure having dimensions such as diameter and length on the nanometer scale, i.e., 1-100 nm. Nanowire structures may be simple and substantially straight, or may comprise at least one node along its length from which at least two separate branches extend. Such nanowire structures may be referred to as nanotrees or nanowire tree structures.

[0011] The term "transversely and longitudinally wrapped" may refer to wrapping the nanowire structure both laterally or radially and longitudinally or longitudinally. The entire nanowire structure, including all eventual branches, faces and surfaces, may be covered by the solid electrolyte material forming the solid electrolyte layer.

[0012] Adding such nanowire structures may advantageously increase the effective contact area between the anode and the solid electrolyte, thus increasing the charge capacity of the battery and potentially increasing the proportion of charge-carrying ions. For example, lithium ions may alloy with the anode material. In addition, utilizing nanowire structures may mitigate the volume expansion of some materials during the operation of the battery. For example, a bulk silicon anode may expand 300-400 percent during lithiation, i.e., in the process of charging the battery when the charge carriers are lithium ions. Nanostructures, such as nanowires, are advantageous because their volume expansion may be much less severe than that of bulk materials. The advantage of this nanostructure may be due to their more localized and distributed volume expansion compared to the expansion of the bulk layer as a unit. This reduction in the volume expansion problem may be even more relevant for solid electrolyte batteries, since solids generally have less mechanical movement than liquids. Moreover, nanostructures such as these may be fabricated by structured and well-defined methods, and even if some irregularity occurs, the effective contact area may still be increased.

[0013] Each nanowire structure in the plurality of nanowire structures may include a longitudinal trunk and a plurality of branches extending from the longitudinal trunk, and the longitudinal trunks in the plurality of nanowire structures may be disposed in a vertical direction relative to a top surface of the anode layer.

[0014] The term "vertically arranged" may refer to aligning the entire nanowire structure, and in particular the vertical trunk, such that they extend in a direction substantially perpendicular and perpendicular to the top surface of the anode layer. This direction may alternatively be understood as corresponding to the vertical direction of the layer structure. Having a tree-shaped nanowire structure with both trunks and branches may further increase the effective contact area between the anode and the solid electrolyte and the battery charge capacity. In addition, the tree-shaped nanowire structure may further reduce the volume expansion problem discussed above.

[0015] A plurality of tree-shaped nanowire structures or nanotrees may be visually compared or likened to a nanoforest.

[0016] The multiple nanowire structures may comprise silicon.

[0017] Such nanowire structures may be advantageous because they are relatively easy to form due to the large number of silicon structures and processing methods available. Because silicon nanowire structures effectively extend the anode, the same benefits of using silicon as the anode material would apply; i.e., charging capacity may be increased.

[0018] The multiple nanowire structure may include gallium nitride.

[0019] Similar to the above, gallium nitride nanowire structures extending the anode may also improve the charge capacity of solid-state batteries.

[0020] The anode layer may include a plurality of metal vias connecting the plurality of nanowire structures to the anode current collector metal layer.

[0021] In that way, a lower resistance, or more ohmic conductive path may be provided as a basis for the nanowire structure.

[0022] The solid electrolyte layer may include lithium phosphate.

[0023] Lithium phosphate or a compound containing lithium phosphate may be considered an advantageous material for the solid electrolyte layer in the layer structure of a solid-state battery. Lithium phosphate may enable the transport of lithium ions between the anode and cathode in a solid-state battery by diffusion through atomic vacancies in the lattice of the solid electrolyte material.

[0024] The cathode layer may include lithium cobalt oxide or other metal oxides.

[0025] Lithium cobalt oxide may be considered an advantageous material for the cathode layer.

[0026] The cathode current collector metal layer may comprise aluminum.

[0027] The aluminum may provide a low resistance or suitable ohmic conductive path to the cathode layer.

[0028] The anode current collector metal layer may comprise copper.

[0029] Copper may provide a low resistance or suitable ohmic conductive path to the anode layer and also to the nanowire structure, if present.

[0030] According to a second aspect of the present invention, there is provided a method for producing a layer structure of a solid-state battery, the method comprising the steps of: Providing an anode layer; forming a plurality of nanowire structures on the anode layer, each nanowire structure including a longitudinal trunk and a plurality of branches extending from the longitudinal trunk, the longitudinal trunks of the nanowire structures being disposed in a vertical direction relative to a top surface of the anode layer; depositing a solid electrolyte layer on the anode layer, the solid electrolyte layer laterally and vertically encapsulating the nanowire structure; depositing a cathode layer on the solid electrolyte layer; depositing a cathode current collector metal layer on the cathode layer; depositing an anode current collector metal layer on the bottom surface of the anode layer.

[0031] The term "forming" may refer to any method or technique for forming a layer or structure. The term "depositing" may refer to the use of any method or technique for forming a layer or structure by the addition of material. Examples of deposition techniques may include chemical vapor deposition (CVD), physical vapor deposition (PVD), metal organic vapor phase epitaxy (MOVPE), sputtering, evaporation, etc. Thus, the forming step may refer to depositing. It should be understood that the anode current collector metal layer is deposited on the bottom surface of the anode layer, i.e., not on or above the anode layer when considering the vertical direction of the layer structure or stack.

[0032] Such a method may be used to manufacture a layer structure of a solid-state battery according to the first embodiment. Thus, the advantages may closely correspond to those described in the first embodiment. In summary, by using existing microelectronic fabrication methods and techniques, the method may provide a relatively low-complexity method for manufacturing a layer structure of a solid-state battery. The method may enable close integration with electronic devices and miniaturization.

[0033] The method may further include etching holes through the anode layer from a bottom surface of the anode layer, and the step of depositing an anode current collector metal layer on the bottom surface of the anode layer may further include filling the holes with a material that is the same as a material of the anode current collector metal layer.

[0034] This etching and filling addition may be understood to correspond to forming a via at the base of the nanowire structure as described in the first embodiment. Similar advantages and beneficial effects therefore apply. Such backside wafer vias may be provided by plasma etching of silicon oxide or silicon nitride as a hard mask for deep reactive ion etching (DRIE) of silicon.

[0035] The method may further include aligning holes through the anode layer with the plurality of nanowire structures.

[0036] In that way, a more ideal conductive path may be obtained between the anode contact and the nanowire structure.

[0037] The step of forming a plurality of nanowire structures includes: forming a plurality of stem seed particles on an upper surface of the anode layer; epitaxially growing longitudinal stems of a plurality of nanowire structures from the plurality of stem seed particles; depositing branch seed particles on a vertical trunk; The method may include epitaxially growing a plurality of nanowire structure branches from a branch seed particle.

[0038] Forming nanowire structures by particle formation, e.g., deposition and subsequent particle-mediated epitaxy, may be an effective method for forming a primary nanowire structure, i.e., a tree-shaped nanowire structure comprising a vertical trunk, and secondary nanowire structures, i.e., branches where the primary nanowire structure serves as a base for the secondary nanowire structures.

[0039] The branches may be understood to grow substantially laterally from the longitudinal trunk, and the branch seed particles may be understood to be deposited on the radial or lateral surfaces and along the entire length of the longitudinal trunk.

[0040] Further scope of applicability of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given for purposes of illustration only. Thus, various changes and modifications within the scope of the present invention will become apparent to those skilled in the art from this detailed description.

[0041] Therefore, this invention is not limited to the particular components of the apparatus described or the operation of the methods described, as such apparatus and methods may vary, and it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0042] It should be noted that, as used in this specification and the appended claims, the words "a," "an," "the," and "said" are intended to refer to one or more elements, unless the context clearly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, etc. Furthermore, the words "comprising," "include," "containing," and similar expressions do not exclude other elements or steps. [Brief description of the drawings]

[0043] These and other aspects of the invention will now be described in more detail with reference to the accompanying drawings, which should not be considered as limiting, but instead for purposes of illustration and understanding.

[0044] As illustrated in the figures, the dimensions of layers and regions may be exaggerated for illustrative purposes and, thus, are provided to illustrate general structures. Like reference numbers refer to like elements throughout.

[0045] [Figure 1] FIG. 1 shows a cross-sectional view of the layer structure of a solid-state battery. [Diagram 2] FIG. 2 shows a cross-sectional view of the layer structure of a solid-state battery with nanowire structures. [Diagram 3] FIG. 3 shows a cross-sectional view of the layer structure of a solid-state battery with nanowire structures and vias. [Figure 4]FIG. 4 shows a flow chart with steps for forming a layer structure of a solid-state battery. [Diagram 5] 5a-5h show cross-sectional views of the layer structure of a solid-state battery at various stages of its fabrication. [Figure 6] FIG. 6 shows a flow chart having steps for forming a nanowire structure. [Figure 7] 7a-d show cross-sectional views of nanowire structures at various stages of their formation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which presently preferred embodiments of the invention are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather these embodiments are provided for thoroughness and completeness and to fully convey the scope of the invention to those skilled in the art.

[0047] FIG. 1 shows a cross-sectional view of a layer structure 100 of a solid-state battery. an anode current collector metal layer 110; an anode layer 120 disposed on the anode current collector metal layer; a solid electrolyte layer 140 disposed laterally on the anode layer; a cathode layer 150 disposed on the solid electrolyte layer; a cathode current collector metal layer 160; The anode layer comprises silicon.

[0048] The anode current collector metal layer 110 may comprise or consist essentially of copper. The anode current collector metal layer 110 may alternatively or additionally comprise one of the following other metallic materials: gold, silver, platinum, nickel, titanium, zinc, chromium, tin, lead, manganese, cobalt, and iron. The anode current collector metal layer 110 may comprise an alloy material.

[0049] The anode layer 120 is <111> The anode layer 120 may comprise silicon. The anode layer 120 may be a crystalline silicon substrate or wafer. The anode layer 120 may comprise, or consist essentially of, gallium nitride. The anode layer 120 may comprise a thin upper sublayer of gallium nitride disposed on a lower sublayer of silicon. The anode layer 120 including GaN may be passivated with hydrogen. Lithium may be incorporated or alloyed into the anode layer 120.

[0050] The solid electrolyte layer 140 may include or consist essentially of lithium phosphate (Li3PO4). The solid electrolyte layer 140 may additionally or alternatively include or consist essentially of other materials, such as lithium iron phosphate (Li3FePO4) or lithium phosphorus oxynitride (LiPON).

[0051] Other lithium compounds may also be utilized in the solid electrolyte layer 140 .

[0052] The solid electrolyte layer 140 may feature atomic vacancies at lithium atomic lattice sites to allow conduction by diffusion of lithium ions through the solid electrolyte layer 140. The solid electrolyte layer 140 may include magnesium substitution or impurity atoms to restore charge balance within the lattice that may be lost by introducing lattice lithium vacancies.

[0053] The solid electrolyte layer 140 may have a thickness in the range of 500 to 5000 nm.

[0054] Cathode layer 150 may include or consist essentially of lithium cobalt oxide (LiCoO2). Cathode layer 150 may alternatively or additionally include other metal oxide-based materials.

[0055] The cathode current collector metal layer 160 may comprise or consist essentially of aluminum. The cathode current collector metal layer 160 may alternatively or additionally comprise one of the following other metallic materials: gold, silver, platinum, nickel, titanium, zinc, chromium, tin, lead, manganese, cobalt, and iron. The cathode current collector metal layer 160 may comprise an alloy material.

[0056] 2 shows a layer structure of the solid-state battery 100 further comprising a plurality of nanowire structures 130. The nanowire structure 130 may be disposed on the anode layer 120. The nanowire structure 130 may be laterally and vertically enveloped by a solid-state electrolyte layer 140.

[0057] Each nanowire structure 130 in the plurality of nanowire structures may include a longitudinal trunk 132 and a plurality of branches 134 extending from the longitudinal trunk. The longitudinal trunks in the plurality of nanowire structures may be disposed perpendicular to the top surface 122 of the anode layer 120.

[0058] The nanowire structures 130 may be arranged in a hexagonal pattern on the top surface 122 of the anode layer 120. The vertical stems 132 of the nanowire structures 130 may be spaced apart from the nearest other vertical stems 132 at intervals ranging from 100 to 1000 nm. More preferably, the intervals are in the range of 250 to 750 nm. Most preferably, the intervals are in the range of 400 to 600 nm.

[0059] The nanowire structures 130 may alternatively be disposed on the anode layer 120 with each nanowire structure 130 in any orientation. Such a configuration may be less complex while still increasing the effective anode electrolyte contact area.

[0060] The longitudinal stems 132 may have a length in the range of 500 to 5000 nm. More preferably, the length is in the range of 1000 to 3000 nm. Most preferably, the length is in the range of 1500 nm to 2500 nm.

[0061] The branches 134 may have a length in the range of 50 to 500 nm. More preferably, the length is in the range of 50 to 250 nm. Most preferably, the length is in the range of 50 to 150 nm.

[0062] The nanowire structures 130 may include or consist essentially of silicon. The nanowire structures 130 have a crystal lattice orientation that corresponds to the longitudinal direction of the nanowire structures. <111> The silicon may include crystalline silicon having the following structure:

[0063] The plurality of nanowire structures may comprise or consist essentially of gallium nitride. The nanowire structure 130 has a crystal lattice orientation that corresponds to the longitudinal direction of the nanowire structure. <0001> The gallium nitride nanowire structure 130 may include crystalline gallium nitride having a hydrogen passivation layer on the surface and faces of the nanowire structure 130 to saturate unsaturated dangling bonds at the gallium nitride surface.

[0064] The nanowire structures 130 may incorporate or be alloyed with lithium alloys on their surface or in the bulk lattice.

[0065] 3 shows an anode layer 120 with a plurality of metal vias 224 connecting a plurality of nanowire structures 130 to the anode current collector metal layer 110. The metal vias 224 may comprise or consist essentially of the same material present in the anode current collector metal layer 110.

[0066] FIG. 4 shows a flow chart of a method for manufacturing a layer structure 100 of a solid-state battery. The method comprises: Providing an anode layer 120 (S1002); forming (S1004) a plurality of nanowire structures 130 on the anode layer 120, each nanowire structure 130 including a vertical trunk 132 and a plurality of branches 134 extending from the vertical trunk, the vertical trunks 132 of the nanowire structures 130 being formed perpendicular to the upper surface 122 of the anode layer 120; depositing (S1006) a solid electrolyte layer 140 on the anode layer 120, the solid electrolyte layer 140 laterally and vertically encapsulating the plurality of nanowire structures 130; depositing (S1008) a cathode layer 150 on the solid electrolyte layer 140; depositing (S1010) a cathode current collector metal layer 160 on the cathode layer 150; 10. Depositing (S1012) an anode current collector metal layer 110 on the bottom surface 326 of the anode layer 120.

[0067] The nanowire structures 130 may be formed by MOVPE or CVD methods. The method may be via seed particles. The pattern in which the nanowire structures 130 are arranged may be formed using lithography techniques such as ultraviolet lithography (UVL), electron beam lithography (EBL) and nanoimprint lithography (NIL). Pattern transfer may be achieved via etching methods.

[0068] Nanosphere lithography (NSL) is used to etch the entire vertical stem 132. It may be used in conjunction with a chlorine-based plasma etch. That way, the need for MOVPE may be avoided, at least to form the vertical trunks. The nanowire structure 130 may be passivated in-situ before, during, and after the MOVPE process. The nanowire structure 130 may be passivated with hydrogen.

[0069] The method may further include incorporating or alloying lithium into the surface or bulk lattice of the nanowire structure 130. This may be accomplished by electrochemical processing. Lithium may be deposited on the nanowire structure 130 prior to deposition of the solid electrolyte layer 140 (S1006). The lithium may be deposited by thermal evaporation.

[0070] The solid electrolyte layer 140 may be deposited (S1006) by a CVD process. The solid electrolyte layer 140 may be deposited by a PVD or sputtering process. The sputtering process may be a pulsed DC (direct current) or RF (radio frequency) based sputtering process. The solid electrolyte layer 140 may encapsulate all of the lithium deposited on the nanowire structure 130.

[0071] The cathode layer 150 may be deposited by a CVD method (S1008). The cathode current collector metal layer 160 may be deposited by a PVD method (S1010). The anode current collector metal layer 110 may be deposited by a PVD method (S1012).

[0072] 4 also shows how the method may further include etching (S3002) holes 328 through the anode layer 120 from the bottom surface 326 of the anode layer 120. In this event, the step of depositing (S1012) the anode current collector metal layer 110 on the bottom surface 326 of the anode layer 120 further includes filling the holes 328 with the same material as the anode current collector metal layer 110. The filling of the holes 328 may correspond to the vias 224 of FIG.

[0073] Also, as shown in FIG. 4, the method may further include aligning (S4002) holes 328 through the anode layer 120 with the multiple nanowire structures, i.e., aligning each hole 328 so that it corresponds to the position of one nanowire structure 130.

[0074] The holes 328 may be etched (S3002) by a reactive ion etching (RIE) process.

[0075] 5a-5h show cross-sectional views of layers and structures of a solid-state battery layer structure 100 at various stages of its fabrication.

[0076] FIG. 5a shows the anode layer 120 provided (S1002), which is the base for subsequent processing steps.

[0077] FIG. 5b shows a nanowire structure in which multiple nanowire structures 130, each having a vertical trunk 132 and branches 134, are formed (S1012), and the vertical trunks 132 of the nanowire structures 130 are formed vertically toward the top surface 122 of the anode layer 120 (S1004).

[0078] FIG. 5 c shows a solid electrolyte layer 140 deposited (S 1006 ) on the anode layer 120 so as to laterally and vertically encase the multiple nanowire structures 130 .

[0079] FIG. 5 d shows a cathode layer 150 deposited (S 1008 ) on the solid electrolyte layer 140 .

[0080] 5e shows a cathode current collector metal layer 160 deposited (S1010) on the cathode layer 150. The solid-state battery layer structure may be flipped over after step S1010 to accommodate subsequent processing steps.

[0081] FIG. 5f shows the anode current collector metal layer 110 being deposited (S1012) on the bottom surface 326 of the anode layer 120, thus completing the layer structure 100 of the solid-state battery.

[0082] 5g-h show an alternative method for completing layer structure 100 compared to the method shown in FIG. 5f.

[0083] Figure 5g shows a hole 328 that has been etched (S3002) from the bottom, through the anode layer 120 from its bottom surface 326. The hole 328 is also shown to be aligned (S4002) with the nanowire structure 130.

[0084] FIG. 5h shows the anode current collector metal layer 110 deposited (S1012) on the bottom surface 326 of the anode layer 120 and into the holes 328 through the anode layer 120, thus completing the layer structure 100 of the solid-state battery.

[0085] 6 shows a flow chart of the step of forming (S1004) a plurality of nanowire structures 130. The step (S1004) includes: forming (S2002) a plurality of stem seed particles 436 on the upper surface 122 of the anode layer 120; epitaxially growing (S2004) longitudinal stems 132 of a plurality of nanowire structures 130 from the plurality of stem seed particles 436; depositing (S2006) branch seed particles 438 on the vertical trunk 132; epitaxially growing (S2008) the branches 134 of the plurality of nanowire structures 130 from the branch seed particle 438.

[0086] The trunk and branch seed particles 436, 438 may be, for example, gold seed particles. The trunk and branch seed particles 436, 438 may include other materials besides gold, such as, for example, silver, palladium, cobalt, bismuth, and platinum. The trunk and branch seed particles 436, 438 may be deposited using aerosol deposition. The deposition or formation of multiple seed particles 436, 438 may be formed on their respective surfaces or structures, preferably with or without mutual alignment. The trunk seed particles 436 may be formed using lithography-based patterning techniques. Such techniques may include forming a layer of gold on the anode layer 120 by electroplating, deposition, or sputtering followed by lithography-based patterning, such as resist coating, exposure, and etching steps to achieve a well-defined pattern of the trunk seed particles 436 remaining on the top surface 122 of the anode layer 120.

[0087] The nanowire structure 130 may be grown using seed particles mediated epitaxy. Essentially, this may mean that the crystalline nanowire structure 130 is epitaxially grown from the seed particles 436, 438. The seed particles 436, 438 may first absorb precursor gases.

[0088] 7a-d are cross-sectional or side views of nanowire structures 130 at different stages of their formation.

[0089] FIG. 7 a shows a plurality of stem seed particles 436 formed (S 2002 ) on the top surface 122 of the anode layer 120 .

[0090] FIG. 7b shows vertical stems 132 that have been epitaxially grown (S2004).

[0091] FIG. 7 c shows branch seed particles 438 deposited (S 2006 ) on the vertical trunk 132 .

[0092] FIG. 7d shows the epitaxially grown (S2008) branch 134.

[0093] Additionally, variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

Claims

1. an anode current collector metal layer (110); an anode layer (120) disposed on the anode current collector metal layer; a solid electrolyte layer (140) disposed laterally on said anode layer; a cathode layer (150) disposed on the solid electrolyte layer; a cathode current collector metal layer (160); a plurality of nanowire structures (130) comprising silicon and / or gallium nitride, the nanowire structures (130) disposed on the anode layer (120), the nanowire structures (130) being laterally and vertically enveloped by the solid electrolyte layer (140); the anode layer comprises silicon and a plurality of metal vias (224) connecting the plurality of nanowire structures to the anode current collector metal layer (110); A layer structure (100) of a solid-state battery.

2. 10. The layer structure of the solid-state battery of claim 1, wherein the anode layer comprises gallium nitride.

3. 3. The layer structure of a solid-state battery of claim 1, wherein each nanowire structure in the plurality of nanowire structures comprises a vertical trunk (132) and a plurality of branches (134) extending from the vertical trunk, the vertical trunks of the plurality of nanowire structures being disposed perpendicular to the top surface (122) of the anode layer.

4. 4. The layer structure of a solid-state battery according to claim 1, wherein the solid electrolyte layer comprises lithium phosphate.

5. 5. A layer structure of a solid-state battery according to claim 1, wherein the cathode layer comprises lithium cobalt oxide or another metal oxide.

6. 6. The layer structure of a solid-state battery according to claim 1, wherein the cathode current collector metal layer comprises aluminum.

7. 7. The layer structure of a solid-state battery according to claim 1, wherein the anode current collector metal layer comprises copper.

8. A method for manufacturing a layer structure (100) for a solid-state battery, the method comprising the steps of: Providing (S1002) an anode layer (120) comprising silicon; forming (S1004) a plurality of nanowire structures (130) including silicon and / or gallium nitride on the anode layer, the nanowire structures (130) being formed vertically on the top surface (122) of the anode layer; depositing (S1006) a solid electrolyte layer (140) on the anode layer, the solid electrolyte layer laterally and vertically encapsulating the plurality of nanowire structures; depositing (S1008) a cathode layer (150) on the solid electrolyte layer; depositing (S1010) a cathode current collector metal layer (160) on the cathode layer; Etching (S3002) holes (328) through the anode layer (120) from a bottom surface (326) of the anode layer; depositing (S1012) an anode current collector metal layer (110) on the bottom surface (326) of the anode layer and filling the holes with a material identical to that of the anode current collector metal layer; Methods including:

9. The method of claim 8 , further comprising aligning (S4002) the holes through the anode layer with the plurality of nanowire structures.

10. forming the plurality of nanowire structures, forming (S2002) a plurality of stem seed particles (436) on the upper surface of the anode layer; epitaxially growing (S2004) longitudinal stems of the nanowire structures from the stem seed particles; depositing (S2006) branch seed particles (438) on said vertical trunks; epitaxially growing (S2008) the plurality of nanowire structure branches from the branch seed particles; 10. The method according to claim 8 or 9.

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