Patent Description:
The present invention relates generally to connectors, and more particularly to silicon flexible connectors.

In many large electronic applications it is desirable to connect electrical devices together for adding functionality and/or for increasing capacity. These electrical devices are typically connected to one another through one or more electrical connectors. An electrical connector is an electromechanical device used to join electrical conductors and create an electrical circuit between electrical devices. Thousands of configurations of connectors are manufactured for power, data, and audiovisual applications. Electrical connectors essentially consist of two classes of materials: conductors and insulators. Properties important to conductor materials are contact resistance, conductivity, mechanical strength, formability, and resilience. Insulators must have a high electrical resistance, withstand high temperatures, and be easy to manufacture for a precise fit. <CIT> describes a cable, and a process of production thereof, the cable having a plurality of flat cables each comprised of a plurality of ribbon-shaped conductors and an insulating covering layer covering the ribbon-shaped conductors. <CIT> describes a method for fabricating a thin-film interconnector.

In one example, an electrical connection device is provided and includes a first electrical connector having vias formed therein and electrical contacts formed in the vias and a second electrical connector having vias formed therein and second electrical contacts formed in the vias. A flexible silicon connector section connects the first electrical connector and the second electrical connector. The first electrical connector, the second electrical connector, and the flexible silicon connector section being formed from a single piece of flexible silicon material. The connector section includes flexible strands separated by slots, where the flexible strands are flexible in directions orthogonal to a longitudinal direction of the connector section. The flexible strands include metal traces deposited therein to provide an electrical connection between the first electrical connector and the second electrical connector.

In still yet another example, a method of fabricating an electrical connection assembly includes providing a single piece of silicon material having metal traces disposed therein. An electrically conductive material is deposited in vias formed in each end of the single piece of silicon material via a first etching process to form contacts that connect with the metal traces. Slots are formed in a portion of a connector section of the single piece of silicon material via a second etching process, where the slots are defined between strands of the connector section. Channels and integrated strands are formed in a support structure area of the connector section via a third etching process, where the channels being formed between the integrated strands. A backside of an exposed portion of the connector section of the single piece of silicon material is etched via a fourth etching process to form an opening such that the slots extend through the connector section to thereby release the strands and to form a support structure. The support structure is comprised of a base and the integrated strands attached to the base in the support structure area of the connector section.

Silicon electrical connection devices are comprised of a pair of silicon electrical connectors comprised of silicon blocks and a connector section comprised of a flexible thin silicon section connecting the pair of electrical connectors. The connector section is comprised of a single uniform flexible sheet of thin silicon material. The thin (e.g., <NUM>-<NUM> microns thick) silicon section is flexible in the z-direction, but flexibility of the thin silicon section is inhibited in the y-direction. Thus, any twisting or movement in the y-direction could result in the thin silicon section shearing in either the x- or y-direction. In addition, in order to compensate for the non-uniform orientation (e.g., varied thicknesses, rotated with respect to each other, on different planes, etc.) between electronic components that the silicon electrical connector connects, the thin silicon section must be able to flex in both the y- and z-directions without shearing.

Disclosed herein is an improved integrated electrical connection device comprised of a pair of electrical connectors and a connector section comprised of flexible strands connecting the pair of electrical connectors, where the connector section has the capabilities of flexing in both the y-, and z-directions. Specifically, the connector section includes slots defined in the single uniform flexible sheet of thin material to create thin narrow flexible strands. Thus, since the surface area and the amount of material of the connector section in the y-direction of is reduced, the flexibility of the connector section in both the y- and z-directions increases. The thin narrow flexible strands can have an aspect ratio of approximately <NUM>:<NUM> (i.e., the thickness (t) and the width (w) of each flexible strand are approximately the same) or can have a thickness (t) that is greater or less than the width (w) without sacrificing flexibility. In addition, the flexible strands can include metal traces for electrical conductivity. The flexible strands can include a thin support structure (layer) or crossbar and/or a flexible polymer dielectric coating to increase the mechanical strength of the electrical connection device without sacrificing flexibility.

<FIG> are a plan and side view respectively of an example integrated electrical connection device (hereinafter "connection device") <NUM>. The connection device <NUM> is made from a flexible silicon material. The connection device <NUM> includes first and second electrical connectors <NUM>, <NUM> and a connector section <NUM>. The connector section <NUM> connects the first and second electrical connectors <NUM>, <NUM> to each other. Electrical contacts <NUM> are arranged in the first and second electrical connectors <NUM>, <NUM> to provide an electrical connection to electronic components. The connector section <NUM> includes metal traces <NUM> that are connected to the electrical contacts <NUM> in the first and second electrical connectors <NUM>, <NUM> to electrically connect the first and second electrical connectors <NUM>, <NUM> to each other.

In the example illustrated in <FIG>, the connector section <NUM> is comprised of a solid uniform sheet of a flexible silicon material that can flex in the z-direction as indicated by the coordinate system (CS). The configuration of the solid uniform sheet of the connector section <NUM>, however, inhibits flexing in the y-direction due to the amount of surface area and actual amount of material of the solid uniform sheet in y-direction. This configuration creates risks with handling and use when connecting electronic components together that have different orientations (e.g., varied thicknesses, rotated with respect to each other, on different planes, etc.). Thus, if the connection device <NUM> is twisted in a direction that does not facilitate flexibility, there is a risk that the connection device <NUM>, and more specifically, the connector section <NUM> will shear in the x- or y-direction.

<FIG>, and <FIG> are a plan view and two side views respectively of another example of a flexible electrical connection device (hereinafter "connection device") <NUM>. The connection device <NUM> includes first and second electrical connectors <NUM>, <NUM> and a connector section <NUM>. The connection device <NUM>, including the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM>, can be made from a flexible silicon material.

First and second electrical contacts <NUM>, <NUM> are arranged in both the first and second electrical connectors <NUM>, <NUM> respectively. In one example, as illustrated in <FIG>, the first and second electrical contacts <NUM>, <NUM> can extend to a bottom surface of the each of the first and second electrical connectors <NUM>, <NUM>. In another example, the electrical contacts <NUM>, <NUM> can extend to a top surface of each of the first and second electrical connectors <NUM>, <NUM>, as described in <CIT>. The first and second electrical contacts <NUM>, <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to electronic components.

The connector section <NUM> is comprised of multiple flexible strands <NUM> of the flexible silicon material. The flexible strands <NUM> have a thickness of approximately <NUM>-<NUM> microns that connect the first and second electrical connectors <NUM>, <NUM> to each other. The flexible strands <NUM> are spaced apart by slots <NUM> (see <FIG> and <FIG>) at a predetermined distance (e.g., <NUM>-<NUM> microns) to facilitate flexibility in directions that are orthogonal (y- and z-directions) to a longitudinal direction (x-direction) indicated by the coordinate system (CS) in <FIG> without sacrificing the mechanical integrity of the connection device <NUM>. As will be described in more detail below, the slots <NUM> are defined in a solid uniform sheet of the flexible silicon material to form the flexible strands <NUM>.

Metal traces <NUM> are arranged in or on one or more of the flexible strands <NUM>. For example, the metal traces <NUM> can be arranged in or on one flexible strand <NUM>, two flexible strands <NUM>, three flexible strands <NUM> (as illustrated in the figures), etc. up to all of the flexible strands <NUM>. The metal traces <NUM> are connected to the first and second electrical contacts <NUM>, <NUM> in both the first and second electrical connectors <NUM>, <NUM> respectively. Thus, the metal traces <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to each other. As a result, an electrical connection is achieved between an electronic component coupled to the first electrical connector <NUM> and an electronic component coupled to the second electrical connector <NUM>.

In one example, a thickness (T) of the first and second electrical connectors <NUM>, <NUM> can have a thickness that is greater than a thickness (t) of the connector section <NUM>, as illustrated in <FIG>. In another example, the thickness (T) of the first and second electrical connectors <NUM>, <NUM> can have a thickness that is approximately the same than the thickness (t) of the connector section <NUM>, as illustrated in <FIG>. In still another example, a width (W) of the first and second electrical connectors <NUM>, <NUM> can be approximately the same as a total width (tw) of the connector section <NUM>, as illustrated in <FIG>. Still referring to <FIG>, the total width (tw) is defined as a sum of a width (w) of each flexible strand <NUM>, see <FIG>, plus a sum of a width of each slot <NUM> defined between the flexible strands <NUM>.

<FIG> is a cross-sectional view taken along line A-A of the connection device <NUM> illustrated in <FIG>. The metal traces <NUM> have been omitted from <FIG> for clarity. As illustrated in <FIG>, each flexible strand <NUM> has a width (w) and a thickness (t). In one example, an aspect ratio of each flexible strand can be approximately <NUM>:<NUM>. In other words, the width (w) and the thickness (t) of each flexible strand <NUM> can be approximately the same. For example, both the width (w) and the thickness (t) can be approximately <NUM> microns. In other examples, the width (w) of each flexible strand <NUM> can be greater or less than the thickness (t).

In the examples illustrated in <FIG>, since the amount of surface area and the actual amount of material of the connector section <NUM> in the y-direction is reduced, the flexibility of the connector section in both the y- and z-directions increases. Specifically, forming slots in the connector section <NUM> reduces the amount of material in the connector section <NUM> thereby allowing the connector section to flex in both the y- and z-directions.

<FIG> are plan views of other examples of a flexible electrical connection device (hereinafter "connection device") 300A, 300B. The connection devices 300A, 300B include first and second electrical connectors <NUM>, <NUM> and a connector section <NUM>. The connection devices including the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM> can be made from flexible silicon material. In one example, the electrical devices 300A, 300B can be formed from a single piece of the flexible material such that the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM> are an integrated unit. In another example, the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM> can be formed from individual pieces of the flexible material that are then bonded together to form the electrical connection devices 300A, 300B.

First and second electrical contacts <NUM>, <NUM> are arranged in both the first and second electrical connectors <NUM>, <NUM> respectively. The electrical contacts <NUM>, <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to electronic components.

The connector section <NUM> is comprised of multiple flexible strands <NUM> of the flexible silicon material. The flexible strands <NUM> have a thickness of approximately <NUM>-<NUM> microns that connect the first and second electrical connectors <NUM>, <NUM> to each other. The flexible strands <NUM> are spaced apart by slots <NUM> at a predetermined distance (e.g., <NUM>-<NUM> microns) to facilitate flexibility in directions that are orthogonal (y- and z-directions) to a longitudinal direction (x-direction) indicated by the coordinate system (CS) in <FIG> without sacrificing the mechanical integrity of the connection device 300A, 300B. As will be described in more detail below, the slots <NUM> are defined in a solid uniform sheet of the flexible silicon material to form the flexible strands <NUM>.

Metal traces <NUM> are arranged in or on one or more of the flexible strands <NUM>. The metal traces <NUM> are connected to the first and second electrical contacts <NUM>, <NUM> in both the first and second electrical connectors <NUM>, <NUM> respectively. Thus, the metal traces <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to each other. As a result, an electrical connection is achieved between an electronic component coupled to the first electrical connector <NUM> and an electronic component coupled to the second electrical connector <NUM>.

<FIG> is a cross-sectional view taken along line B-B of the connection devices 300A, 300B illustrated in <FIG>. The metal traces <NUM> have been omitted from <FIG> for clarity. As illustrated in <FIG>, in the example connection devices 300A, 300B illustrated in <FIG>, the connector section <NUM> further includes a support structure or layer 316A, 316B. The support structure 316A, 316B, is comprised of an ultrathin layer (e.g., <NUM>-<NUM> microns) of the flexible material disposed on either a first (top) surface <NUM> or a second (bottom) surface <NUM> of a portion or all of the flexible strands <NUM>. The support structure 316A, 316B provides additional rigidity and mechanical support for handling without sacrificing flexibility in the y- and z-direction.

The support structure 316A, 316B can be made from the same material as the flexible silicon strands <NUM>. Specifically, the support structure 316A, 316B is formed from the same uniform sheet of flexible silicon material as the flexible strands <NUM>. Thus, a portion or all of the flexible strands <NUM> are integrated with the support structure 316A, 316B. As will be explained below, channels are partially etched (e.g., deep reactive ion etching) into the uniform sheet of flexible material to form the ultrathin layer of the support structure 316A, 316B. Thus, a thickness of the support structure 316A, 316B plus the thickness of the flexible strands <NUM> in an area or region of the support structure 316A, 316B can have a total thickness (tt) that is approximately the same as the width (w) of the flexible strands <NUM>. For example, if the thickness of the uniform sheet is <NUM> microns, the slots will be partially etched such that the remaining thickness of the support structure is <NUM>-<NUM> microns. As a result, the thickness of the flexible strands <NUM> in the region of the support structure will be <NUM>-<NUM> microns thereby totaling <NUM> microns.

The support structure or layer 316A illustrated in <FIG> is a partial support structure that is disposed across a total width (tw) in the y-direction of the flexible strands <NUM>, but is only disposed across a portion of the length in the x-direction of the flexible strands <NUM>. Referring to <FIG>, the total width (tw) is defined as a sum of a width (w) of each flexible strand <NUM>, see <FIG>, plus a sum of a width of each slot <NUM> defined between the flexible strands <NUM>. The connection device 300A can include one (as shown in <FIG>) or more partial support structures 316A in one or more regions of the connector section <NUM>. The partial support structure 316A can be centralized between the first and second electrical connectors <NUM>, <NUM> (as shown in <FIG>) or can be disposed at any location between the first and second electrical connectors <NUM>, <NUM>. The support structure or layer 316B illustrated in <FIG> is a full support region that is disposed across the total width (tw) in the y-direction and across the total length (tl) in the x-direction of the flexible strands <NUM>.

<FIG> is a plan view of another example of a flexible electrical connection device (hereinafter "connection device") <NUM>. The connection device <NUM> includes first and second electrical connectors <NUM>, <NUM> and a connector section <NUM>. The connection device <NUM>, including the first and second electrical connectors <NUM>, <NUM> can be made from a flexible silicon material. In one example, the electrical device <NUM> can be formed from a single piece of the flexible material such that the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM> are an integrated unit. In another example, the first and second electrical connectors <NUM>, <NUM> and the connector section <NUM> can be formed from individual pieces of the flexible material and are bonded together to form the electrical connection device <NUM>.

First and second electrical contacts <NUM>, <NUM> are arranged in both the first and second electrical connectors <NUM>, <NUM> respectively. The first and second electrical contacts <NUM>, <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to electronic components.

The connector section <NUM> is comprised of multiple flexible strands <NUM> of the flexible silicon material. The flexible strands <NUM> have a thickness of approximately <NUM>-<NUM> that connect the first and second electrical connectors <NUM>, <NUM> to each other. The flexible strands <NUM> are spaced apart by slots <NUM> at a predetermined distance (e.g., <NUM>-<NUM> microns) to facilitate flexibility in directions that are orthogonal (y- and z-directions) to a longitudinal direction (x-direction) indicated by the coordinate system (CS) in <FIG> without sacrificing the mechanical integrity of the connection device <NUM>. As will be described in more detail below, the slots <NUM> are defined in a solid uniform sheet of the flexible material to form the flexible strands <NUM>. Metal traces <NUM> are arranged in or on one or more of the flexible strands <NUM>. The metal traces <NUM> are connected to the first and second electrical contacts <NUM>, <NUM> in both the first and second electrical connectors <NUM>, <NUM> respectively. Thus, the metal traces <NUM> electrically connect the first and second electrical connectors <NUM>, <NUM> to each other. As a result, an electrical connection is achieved between an electronic component coupled to the first electrical connector <NUM> and an electronic component coupled to the second electrical connector <NUM>.

<FIG> is a cross-sectional view taken along line C-C of the connection device <NUM> illustrated in <FIG>. The metal traces <NUM> have been omitted from <FIG> for clarity. As illustrated in <FIG>, each flexible strand <NUM> has a width (w) and a thickness (t). In one example, an aspect ratio of each flexible strand <NUM> can be approximately <NUM>:<NUM>. In other words, the width (w) and the thickness (t) of each flexible strand <NUM> can be approximately the same. For example, both the width (w) and the thickness (t) can be approximately <NUM> microns. In other examples, the width (w) of each flexible strand <NUM> can be greater or less than the thickness (t).

As illustrated in <FIG>, the connector section <NUM> further includes a flexible polymer dielectric coating (hereinafter "coating") <NUM>. The coating <NUM> may be applied over the entire connector section <NUM>, as illustrated in <FIG> or may be applied in selected regions of the connector section <NUM>. As shown in <FIG>, the coating <NUM> is deposited in the slots <NUM> defined between the flexible strands <NUM> and covers flexible strands <NUM> such that the coating <NUM> has a thickness (T) greater than the thickness (t) of the flexible strands <NUM>. In another example, the thickness (T) of the coating <NUM> and the thickness (t) of the flexible strands <NUM> could be approximately the same. The polymer dielectric coating <NUM> provides support for handling without sacrificing flexibility in both the y- and z-directions. In addition, the connection device <NUM> including the coating <NUM> may also include the support structure 316A, 316B illustrated in <FIG>.

In the example illustrated in <FIG>, since the amount of surface area and the actual amount of material of the connector section <NUM> in the y-direction is reduced, the flexibility of the connector section in both the y- and z-directions increases. Specifically, forming slots in the connector section <NUM> reduces the amount of material in the connector section <NUM> thereby allowing the connector section to flex in both the y- and z-directions.

<FIG> illustrate an example of a fabrication process of the electrical connection device <NUM> illustrated in <FIG> formed from a single piece (e.g., sheet or block) of silicon material. Though depicted sequentially as a matter of convenience, at least some of the actions shown can be performed in a different order and/or performed in parallel. Alternatively, some implementations may perform only some of the actions shown. Still further, although the example illustrated in <FIG> is an example method illustrating the example configuration of connector section of <FIG>, other methods and configurations are possible.

Referring first to <FIG> illustrate a fabrication process to fabricate the electrical contacts <NUM>, <NUM> in the first and second electrical connectors <NUM>, <NUM> of the electrical connection device <NUM> illustrated in <FIG>. Referring to <FIG>, the fabricating process begins with a single piece (e.g., sheet or block) of silicon material <NUM> having a thickness of approximately <NUM>-<NUM> microns. Although, not illustrated in the fabrication process of <FIG> for simplicity, the metal traces <NUM> are deposited via sputtering, evaporation, plating, etc. in or on a surface of the single piece of material <NUM>.

A first photoresist material layer <NUM> is deposited on a surface of the flexible material <NUM>, as illustrated in <FIG>. The first photoresist material layer <NUM> is patterned and developed <NUM> to expose openings <NUM> in the first photoresist material layer <NUM>, thereby exposing portions of the surface near each end of the single piece of material <NUM> resulting in the configuration in <FIG>. The first photoresist material layer <NUM> can have a thickness that varies in correspondence with the wavelength of radiation used to pattern the first photoresist material layer <NUM>. The photoresist first material layer <NUM> may be formed via spin-coating or spin casting deposition techniques, selectively irradiated (e.g., via deep ultraviolet (DUV) irradiation) and developed to form the openings <NUM>. The configuration in <FIG> undergoes a first etching process (e.g., deep reactive ion etching) <NUM> to fully etch the exposed portions of the single piece of material <NUM> thereby forming vias <NUM> near the ends of the single piece of material <NUM> resulting in the configuration of <FIG>. The first photoresist material layer <NUM> is stripped and the vias <NUM> are filled via a deposition process with an electrically conductive material (e.g. gold, copper, aluminum) to form first and second electrical contacts <NUM>, <NUM> respectively resulting in the configuration in <FIG>. The configuration in <FIG> includes first and second electrical connectors <NUM>, <NUM> and a connector section <NUM>.

<FIG> are cross-sectional views taken along line D-D to the line L of the configuration in <FIG> and illustrate a fabrication process for fabricating the connector section <NUM> and the flexible strands <NUM> illustrated in <FIG>. Referring to <FIG>, a second photoresist material layer <NUM> is deposited on the surface of the connector section <NUM> resulting in the configuration of <FIG>. The second photoresist material layer <NUM> is patterned and developed <NUM> to expose openings <NUM> in the second photoresist material layer <NUM>, thereby exposing portions of the connector section <NUM> within the openings <NUM> resulting in the configuration of <FIG>. The second photoresist material layer <NUM> can have a thickness that varies in correspondence with the wavelength of radiation used to pattern the second photoresist material layer <NUM>. The second photoresist material layer <NUM> may be formed over the connector section <NUM> via spin-coating or spin casting deposition techniques, selectively irradiated (e.g., via deep ultraviolet (DUV) irradiation) and developed to form the openings <NUM>.

The configuration in <FIG> undergoes a second etching process (e.g., deep reactive ion etching) <NUM> to partially etch the exposed portions of the connector section <NUM> thereby forming slots <NUM> and strands <NUM> in the connector section <NUM> resulting in the configuration of <FIG>. The second photoresist material layer <NUM> is stripped resulting in the connector section <NUM> illustrated in <FIG> prior to etching the remainder of the connector section <NUM>. Referring to <FIG>, as an optional process, a flexible polymer dielectric coating <NUM> may be applied over all or a portion of the strands <NUM> and in the slots <NUM> defined between the strands <NUM>. The polymer dielectric coating <NUM> provides support for handling without sacrificing flexibility in both the y- and z-directions.

<FIG> illustrate an example fabrication process for fabricating the final electrical connection device <NUM> illustrated in <FIG> after fabrication of the strands <NUM> in the connector section <NUM>. In this process, a third etching process <NUM> is performed on a backside <NUM> of the connector section <NUM> as described in <CIT>, to thereby release the previously formed strands <NUM>. Specifically, the configuration in <FIG> has been rotated <NUM>° so that the strands <NUM> are located on an opposite side of the backside etch process. A third photoresist material layer <NUM> is deposited on a surface of both the first and second electrical connectors <NUM>, <NUM>, as illustrated in <FIG>. The configuration in <FIG> undergoes the third etching process (e.g., deep reactive ion etching) <NUM> to partially etch an exposed portion of the single piece of material <NUM>, more specifically, to partially etch an exposed portion of the connector section <NUM>, thereby forming an opening <NUM> resulting in the configuration of <FIG>. After the third etching process <NUM>, the slots <NUM> extend through the connector section <NUM> thereby releasing the strands <NUM> resulting in the electrical connection device <NUM> illustrated in <FIG>. The third photoresist material layer <NUM> is stripped and the configuration is again rotated <NUM>° resulting in the configuration in <FIG>. In the final product, the connector section <NUM> is comprised of individual strands <NUM> fabricated from a thin uniform sheet of flexible silicon material and has a thickness of approximately <NUM>-<NUM> microns.

<FIG> illustrate another example fabricating process for fabricating the flexible strands <NUM> of the connector section <NUM> illustrated in <FIG>, where the connector section <NUM> includes the support structure 316A, 316B. The process to fabricate the electrical connectors and contacts is similar to the process described above relating to <FIG> and <FIG> and will not be repeated. Though depicted sequentially as a matter of convenience, at least some of the actions shown can be performed in a different order and/or performed in parallel. Alternatively, some implementations may perform only some of the actions shown. Still further, although the example illustrated in <FIG> is an example method illustrating the example configuration of <FIG>, other methods and configurations are possible.

Referring to <FIG>, a connector section <NUM> is provided and includes metal traces (not shown in this process for simplicity) deposited in or on a surface of the connector section <NUM> via a sputtering, evaporation, plating, etc. process. A second photoresist material layer <NUM> is deposited on a surface of the connector section <NUM>, see <FIG>. A portion of the second photoresist material layer <NUM> is patterned and developed <NUM> to expose openings <NUM> in the second photoresist material layer <NUM>, thereby exposing portions of a top surface of the connector section <NUM> within the openings <NUM>, see <FIG>. Another undeveloped portion <NUM> of the second photoresist material layer <NUM>, however, is not developed in an area <NUM> of the connector section <NUM> where a support structure will be formed, see <FIG>. The second photoresist material layer <NUM> can have a thickness that varies in correspondence with the wavelength of radiation used to pattern the second photoresist material layer <NUM>. The second photoresist material layer <NUM> may be formed over the connector section <NUM> via spin-coating or spin casting deposition techniques, selectively irradiated (e.g., via deep ultraviolet (DUV) irradiation) and developed to form the openings <NUM>.

The configuration in <FIG> undergoes a partial etching (second) process (e.g., deep reactive ion etching) <NUM> to partially etch slots <NUM> approximately <NUM>-<NUM> microns into the exposed portions of the connector section <NUM> resulting in the configuration of <FIG>. The second photoresist layer <NUM> is removed and a third photoresist layer <NUM> is deposited on a surface and patterned to form openings <NUM> resulting in the configuration of <FIG>. The configuration of <FIG> undergoes a third etching process (e.g. deep reactive ion etching) <NUM> of approximately another <NUM>-<NUM> microns to deepen the slots <NUM> and to partially etch openings or channels <NUM> in the connector section <NUM> in the area <NUM> where the support structure will be formed resulting in the configuration of <FIG>. The second photoresist material layer <NUM> is stripped resulting in the configuration of <FIG>.

As described above, an etching (fourth) process is performed on a backside of the connector section <NUM> to thereby form and release strands <NUM> where the slots <NUM> are defined between the strands <NUM>. In addition, one or more support structures <NUM> can be formed where each support structure <NUM> includes a base <NUM> and integrated strands <NUM> having the channels <NUM> defined between the integrated strands <NUM> thereby forming the connector section <NUM> in <FIG>.

The connector section <NUM> is fabricated from a thin uniform sheet of flexible silicon material and has a thickness of approximately <NUM>-<NUM> microns. The base <NUM> of the support structure(s) <NUM> is comprised of an ultrathin layer (e.g., <NUM>-<NUM> microns) of the uniform sheet of flexible material of the connector section <NUM> and provides additional rigidity and mechanical support for handling without sacrificing flexibility in the yand z-direction. As mentioned above, for an example uniform sheet of flexible material having a thickness of <NUM> microns, the one or more support structures will have a resulting thickness of approximately <NUM>-<NUM> microns. Thus, a thickness of the flexible strands in the portion of the support structure will then have a thickness of approximately <NUM>-<NUM> microns.

As an optional process, the polymer dielectric coating <NUM> illustrated in <FIG> may be applied over all or a portion of the flexible strands <NUM>, <NUM> and in the slots <NUM> and channels <NUM> between the flexible strands <NUM>, <NUM>. The combination of the support structure <NUM> and the polymer dielectric coating <NUM> provides support for handling without sacrificing flexibility in both the y- and z-directions.

<FIG> illustrate another example fabricating process for fabricating the flexible strands <NUM> of the connector section <NUM> illustrated in <FIG>, where the connector section <NUM> includes the support structure 316A, 316B. The process to fabricate the first and second electrical connectors and contacts is similar to the process described above relating to <FIG> and <FIG>and will not be repeated. Though depicted sequentially as a matter of convenience, at least some of the actions shown can be performed in a different order and/or performed in parallel. Alternatively, some implementations may perform only some of the actions shown. Still further, although the example illustrated in <FIG> is an example method illustrating the example configuration of <FIG>, other methods and configurations are possible.

Referring to <FIG>, a connector section <NUM> is provided and includes metal traces (not shown in this process for simplicity) deposited in or on a surface of the connector section <NUM> via a sputtering, evaporation, plating, etc. process. A first metal (e.g., aluminum and/or tantalum) mask <NUM> is deposited on a surface of the connector section <NUM>, see <FIG>. A second photoresist material layer <NUM> is deposited on a surface of the first metal mask <NUM>, see <FIG>. The combination of the first metal mask <NUM> and the second photoresist material layer <NUM> comprise a first mask layer. The second photoresist material layer <NUM> can have a thickness that varies in correspondence with the wavelength of radiation used to pattern the second photoresist material layer <NUM>. The second photoresist material layer <NUM> is patterned and developed <NUM> and the first metal mask <NUM> is etched to create openings <NUM> thereby exposing portions of a top surface of the connector section <NUM> within the openings <NUM>, see <FIG>. The second photoresist material layer <NUM> is stripped resulting in the configuration of <FIG>.

A second metal (e.g., aluminum) mask <NUM> is deposited on the remaining portions first metal mask <NUM> and on the exposed portions of the connector section <NUM>, resulting in the configuration of <FIG>. A third photoresist material layer <NUM> is deposited on a surface of the second metal mask <NUM>, see <FIG>. The combination of the second metal mask <NUM> and the third photoresist material layer <NUM> comprise a second mask layer. A portion of the third photoresist material layer <NUM> is patterned and developed <NUM> such that some remaining portions of the third photoresist material layer <NUM> are aligned with some remaining portions of the of the first metal mask <NUM>, see <FIG>. Another undeveloped portion <NUM> of the third photoresist material layer <NUM>, however, is not developed in an area <NUM> of the connector section <NUM> where a support structure will be formed, see <FIG>. The configuration of <FIG> undergoes a second etching process (e.g., deep reactive ion etching) <NUM> to remove exposed portions of the second metal mask <NUM> and to partially etch slots <NUM> into the connector section <NUM> resulting in the configuration of <FIG>. The third photoresist material layer <NUM> is removed resulting in the configuration in <FIG>.

The configuration of <FIG> undergoes a third etching process (e.g. deep reactive ion etching) <NUM> of approximately another <NUM>-<NUM> microns to deepen the slots <NUM> and to partially etch openings or channels <NUM> in the connector section <NUM> in an area <NUM> where the support structure will be formed resulting in the configuration of <FIG>. As described above, an etching (fourth) process is performed on a backside of the connector section <NUM> to thereby form and release strands <NUM> where the slots <NUM> are defined between the strands <NUM>. In addition, one or more support structures <NUM> can be formed where each support structure <NUM> includes a base <NUM> and integrated strands <NUM> having the channels <NUM> defined between the integrated strands <NUM> thereby forming the connector section <NUM> in <FIG>.

As an optional process step, it is not necessary, but the first and second metal masks <NUM>, <NUM> can be stripped via an etching process resulting in the connector section <NUM> of <FIG>. The connector section <NUM> in <FIG> includes the strands <NUM> and the slots <NUM> defined between the strands <NUM>, and the support structure <NUM> that includes the base <NUM> and the integrated strands <NUM> having the channels <NUM> defined between the integrated strands <NUM>.

The connector section <NUM> is fabricated from a thin uniform sheet of flexible silicon material and has a thickness of approximately <NUM>-<NUM> microns. The base <NUM> of the support structure(s) <NUM> are comprised of an ultrathin layer (e.g., <NUM>-<NUM> microns) of the uniform sheet of flexible material of the connector section <NUM> and provides additional rigidity and mechanical support for handling without sacrificing flexibility in the yand z-direction. As mentioned above, for an example uniform sheet of flexible material having a thickness of <NUM> microns, the one or more support structures will have a resulting thickness of approximately <NUM>-<NUM> microns. Thus, a thickness of the flexible strands in the portion of the support structure will then have a thickness of approximately <NUM>-<NUM> microns.

As an optional process, prior to the backside etching process, the polymer dielectric coating <NUM> illustrated in <FIG> may be applied over all or a portion of the flexible strands <NUM>, <NUM> and in the slots <NUM> and channels <NUM> between the flexible strands <NUM>, <NUM>. The combination of the support structure <NUM> and the polymer dielectric coating <NUM> provides support for handling without sacrificing flexibility in both the y- and z-directions.

The improved flexible electrical connection device improves the flexibility of the connection device in several directions with the addition of etching slots into a connector section of the connection device to form flexible strands. Varying the thickness of the flexible strands further increases the flexibility. Increasing the flexibility reduces the risk of failure due to handling and twisting. In addition, forming the slots by an etching process reduces the risks associated with defects along edges of the flexible strands. Still further, incorporating ultra-thin support structures and/or adding a flexible polymer dielectric coating over the flexible strands improves the overall rigidity and strength of the connection device without sacrificing flexibility.

Claim 1:
An electrical connection device (<NUM>, <NUM>, 300A, 300B, <NUM>) comprising:
a first electrical connector (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having vias (<NUM>) formed therein and first electrical contacts (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) formed in the vias;
a second electrical connector (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having vias formed therein and second electrical contacts (<NUM>, <NUM>, <NUM>, <NUM>) formed in the vias; and
a flexible silicon connector section (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) connecting the first electrical connector and the second electrical connector, the first electrical connector, the second electrical connector, and the flexible silicon connector section being formed from a single piece of flexible silicon material (<NUM>), the connector section comprising flexible strands (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) separated by slots (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the flexible strands being flexible in directions orthogonal to a longitudinal direction of the connector section, the flexible strands including metal traces (<NUM>, <NUM>, <NUM>, <NUM>) deposited therein to provide an electrical connection between the first electrical connector and the second electrical connector.