Thermoelectric Device And Method For Fabrication Thereof

Abstract

A thermoelectric device and a method for fabrication thereof are disclosed. The thermoelectric device includes one or more thermocouples electrically connected in series. Each thermocouple includes at least one first thermoelectric element and at least one second thermoelectric element, wherein the thermoelectric elements are maintained in a spaced apart relationship forming an internal cavity there between.

What is claimed is: 
     
         1 . A thermoelectric device comprising at least a first substrate and at least a second substrate arranged substantially parallel to a reference plane, said reference plane defining a first axis, a second axis, and a third axis, said axes being mutually orthogonal, wherein said first axis is orthogonal to said reference plane and said second and said third axes are aligned to said reference plane, wherein said first and said second substrates are retained in a spaced apart relationship along said first axis, and at least one thermocouple, said thermocouple comprising:
 at least one first thermoelectric element disposed on said first substrate extending towards said second substrate along said first axis, wherein said first thermoelectric element comprises a first basal surface facing towards said first substrate, a first apical surface substantially opposite to said first basal surface, and a first lateral surface there between,   at least one second thermoelectric element disposed on said second substrate extending towards said first substrate along said first axis, wherein said second thermoelectric element comprises a second basal surface facing towards said second substrate, a second apical surface substantially opposite to said second basal surface, and a second lateral surface there between,   
       wherein said first thermoelectric element and said second thermoelectric element are disposed such that said first and said second apical surfaces are spaced apart along said first axis, whereby an internal cavity is defined there between. 
     
     
         2 . The thermoelectric device according to  claim 1 , wherein each of said first and said second lateral surfaces of said first and said second thermoelectric elements respectively is electrically and thermally insulated such that a direction of electrical and thermal flux through each of said first and second thermoelectric elements is aligned with said first axis. 
     
     
         3 . The thermoelectric device according to  claim 1 , wherein said first and said second substrates are formed of a thermally conducting and electrically insulating material. 
     
     
         4 . The thermoelectric device according to  claim 3 , wherein said first and said second substrates are provided with one or more structural features and/or one or more material coatings to permit heat dissipation. 
     
     
         5 . The thermoelectric device according to  claim 3 , wherein said first and said second substrates are provided with one or more structural features and/or one or more material coatings to permit heat absorption. 
     
     
         6 . The thermoelectric device according to  claim 1 , wherein said first and said second thermoelectric elements correspond to mutually opposite types of electrical conductivity. 
     
     
         7 . The thermoelectric device according to  claim 1 , wherein said first and said second apical surfaces are electrically interconnected through an intra-couple bridge, wherein said intra-couple bridge comprises individual electrically connecting layers deposited on said first and said second apical surfaces and an intra-couple metallization layer extending along said first axis and interconnecting said individual electrically connecting layers, wherein said intra-couple bridge is at least electrically insulated at a non-contact surface thereof. 
     
     
         8 . The thermoelectric device according to  claim 1 , wherein a first electrically coupling layer is disposed between said first basal surface and said first substrate; and a second electrically coupling layer is disposed between said second basal surface and said second substrate, such that an aggregate of individual electrical potentials across said first and said second thermoelectric elements is accessible across said first and said second electrically coupling layers. 
     
     
         9 . The thermoelectric device according to  claim 8  further comprising at least a first thermocouple and at least a second thermocouple adjacently disposed thereto between said first and said second substrates, wherein individual aggregate electrical potentials across said first and said second thermocouples are formed across corresponding said first and said second electrically coupling layers, and further wherein, said first electrically coupling layer of said first thermocouple is electrically interconnected to said second electrically coupling layer of said second thermocouple through an inter-couple bridge, whereby said first and said second thermocouples are electrically connected in series; wherein said inter-couple bridge comprises an inter-couple metallization layer electrically extending along said first axis from substantially adjacent to said first substrate to substantially adjacent to said second substrate, and electrically interconnecting said first and said second electrically coupling layers, and wherein said inter-couple bridge is at least electrically insulated at a non-contact surface thereof. 
     
     
         10 . The thermoelectric device according to  claim 1 , wherein a plurality of thermocouples extending between said first substrate and said second substrate are arranged in a two dimensional matrix relative to said reference plane, wherein a set of thermocouples arranged in individual rows are electrically interconnected in series and further, individual rows of thermocouples are electrically connected in series, wherein said internal cavity of corresponding thermocouples in adjacent rows is in continuum. 
     
     
         11 . A method for fabricating a thermoelectric device, said method comprising:
 providing a first substrate arranged substantially parallel to a reference plane, said reference plane defining a first axis, a second axis, and a third axis, said axes being mutually orthogonal, wherein said first axis is orthogonal to said reference plane and said second and said third axes are aligned to said reference plane,   forming at least a first thermoelectric element on said first substrate, wherein said first thermoelectric element extends along said first axis and comprises a first basal surface facing towards said first substrate, a first apical surface substantially opposite to said first basal surface, and a first lateral surface there between,   disposing a sacrificial layer on said first thermoelectric element,   forming at least a second thermoelectric element on said sacrificial layer, wherein said second thermoelectric element extends along said first axis and comprises a second basal surface facing away from said first substrate, a second apical surface substantially opposite to said second basal surface and facing towards said sacrificial layer, and a second lateral surface there between,   disposing a second substrate on said second thermoelectric element such that said second substrate is retained in a spaced apart relationship from said first substrate along said first axis and extends in a spatial plane substantially parallel to said reference plane, and   removing said sacrificial layer such that said first and said second apical surfaces of said first thermoelectric element and said second thermoelectric element respectively are spaced apart along said first axis, whereby an internal cavity is defined there between,   
       whereby at least one thermocouple is formed between said first and said second substrates. 
     
     
         12 . The method according to  claim 11  further comprising electrically and thermally insulating each of said first and said second lateral surfaces of said first and said second thermoelectric elements respectively such that a direction of electrical and thermal flux through each of said first and second thermoelectric elements is aligned with said first axis. 
     
     
         13 . The method according to  claim 11 , wherein said first and said second substrates are formed of a thermally conducting and electrically insulating material. 
     
     
         14 . The method according to  claim 13  further comprising providing one or more structural features and/or one or more material coatings on said first and said second substrates to permit heat dissipation therefrom. 
     
     
         15 . The method according to  claim 13  further comprising providing one or more structural features and/or one or more material coatings on said first and said second substrates to permit heat absorption therefrom. 
     
     
         16 . The method according to  claim 11 , wherein said first and said second thermoelectric elements correspond to mutually opposite types of electrical conductivity. 
     
     
         17 . The method according to  claim 11  further comprising forming an intra-couple bridge electrically interconnecting said first and said second apical surfaces, wherein forming said intra-couple bridge comprises:
 disposing a first electrically connecting layer on said first apical surface of said first thermoelectric element prior to disposing said sacrificial layer, 
 forming an intra-couple metallization layer through said sacrificial layer, and 
 disposing a second electrically connecting layer on said sacrificial layer prior to disposing said second thermoelectric element, 
 
       wherein said intra-couple bridge extends along said first axis and interconnects said first and said second electrically connecting layers and further wherein, said intra-couple bridge is at least electrically insulated at a non-contact surface thereof. 
     
     
         18 . The method according to  claim 11  further comprising
 disposing a first electrically coupling layer on said first substrate prior to disposing said first thermoelectric element such that said first electrically coupling layer is disposed between said first basal surface and said first substrate, and 
 disposing a second electrically coupling layer on said second thermoelectric element prior to disposing said second substrate such that said second electrically coupling layer is disposed between said second basal surface and said second substrate, further such that an aggregate of individual electrical potentials across said first and said second thermoelectric elements is accessible across said first and said second electrically coupling layers. 
 
     
     
         19 . The method according to  claim 18  further comprising
 forming at least a first thermocouple and at least a second thermocouple adjacently disposed thereto between said first and said second substrates, wherein individual aggregate electrical potentials across said first and said second thermocouples are formed across corresponding said first and said second electrically coupling layers, 
 electrically interconnecting said first electrically coupling layer of said first thermocouple to said second electrically coupling layer of said second thermocouple through an inter-couple bridge, whereby said first and said second thermocouples are electrically connected in series; wherein said inter-couple bridge comprises an inter-couple metallization layer extending along said first axis from substantially adjacent to said first substrate to substantially adjacent to said second substrate, and electrically interconnecting said first and said second electrically coupling layers, and wherein said inter-couple bridge is at least electrically insulated at a non-contact surface thereof. 
 
     
     
         20 . The method according to  claim 11  further comprising forming a plurality of thermocouples extending between said first and said second substrates, said plurality of thermocouples being arranged in a two dimensional matrix relative to said reference plane, wherein a set of thermocouples arranged in individual rows are electrically interconnected in series and further, individual rows of thermocouples are electrically connected in series, wherein said internal cavity of corresponding thermocouples in adjacent rows is in continuum.