Methods and Apparatus for Forming Multi-Layer Structures Including Use of A Sacrificial Patternable Mold Material

Abstract

Numerous electrochemical fabrication methods and apparatus are provided for producing multi-layer structures (e.g. having meso-scale or micro-scale features) from a plurality of layers of deposited materials using adhered masks (e.g. formed from liquid photoresist or dry film), where two or more materials may be provided per layer where at least one of the materials is a structural material and one or more of any other materials may be a sacrificial material which will be removed after formation of the structure. Materials may comprise conductive materials that are electrodeposited or deposited in an electroless manner. In some embodiments special care is undertaken to ensure alignment between patterns formed on successive layers.

We claim: 
     
         1 . A batch method for forming a plurality of three-dimensional structures simultaneously, comprising:
 (A) forming a plurality of successively formed layers, wherein each successive layer comprises at least two materials and is formed on and adhered to a previously formed layer, one of the at least two materials is a structural material and the other of the at least two materials is a sacrificial material, and wherein each successive layer defines a successive cross-section of the plurality of three-dimensional structures, and wherein the forming of each of the plurality of successive layers comprises:
 (i) depositing a first of the at least two materials; 
 (ii) depositing a second of the at least two materials; 
 (iii) planarizing the first and second materials to set a boundary level for the layer; and 
   wherein the forming of a given one of the plurality of successively formed layers comprises:
 (i) applying a sacrificial material that is a 1st patternable mold material (PMM) to form part of the layer; 
 (ii) patterning the 1st PMM to form a 1st pattern of sacrificial material; 
 (iii) depositing a structural material in the 1st pattern; 
 (iv) planarizing the sacrificial material and the structural material to set a boundary level for the given layer. 
   (B) after the forming of the plurality of successive layers, separating at least a portion of the sacrificial material from multiple layers of the structural material to reveal the plurality of three-dimensional structures.   
     
     
         2 . The method of  claim 1  wherein the PMM is a polymer. 
     
     
         3 . The method of  claim 1  wherein the PMM is a photoresist. 
     
     
         4 . The method of  claim 1  wherein the PMM is a dielectric. 
     
     
         5 . The method of  claim 4  wherein the PMM is provided with a surface of conductive material prior to depositing the structural material. 
     
     
         6 . The method of  claim 5  wherein the conductive material provided in preparation for depositing the structural material is a seed layer deposited. 
     
     
         7 . The method of  claim 6  wherein the conductive material provided in preparation for depositing the structural material further comprises an adhesion layer. 
     
     
         8 . The method of  claim 1  wherein the separating of the sacrificial material comprises plasma etching. 
     
     
         9 . The method of  claim 1  wherein the forming the three-dimensional structure comprises the forming of a plurality of three-dimensional structures simultaneously. 
     
     
         10 . The method of  claim 1  wherein at least one of the depositing steps comprises electroplating. 
     
     
         11 . The method of  claim 1  wherein the depositing of the structural material comprises electroplating. 
     
     
         12 . The method of  claim 1  wherein the given one of the layers comprises at least two layers. 
     
     
         13 . A method for batch forming a plurality of structures, comprising:
 building a plurality of layers on the surface, the plurality of layers including both a structural material and a sacrificial material; and   after building the plurality of layers, removing the sacrificial material from the plurality of layers;   wherein the sacrificial material is a patternable mold material.   
     
     
         14 . The method of  claim 1  wherein the patternable mold material comprises a polymer. 
     
     
         15 . The method of  claim 14  wherein the polymer comprises a photoresist. 
     
     
         16 . The method of  claim 13  wherein the PMM comprises a dielectric. 
     
     
         17 . The method of  claim 13  wherein the PMM is provided with a surface of conductive material prior to depositing the structural material. 
     
     
         18 . The method of  claim 17  wherein the conductive material provided in preparation for depositing the structural material is a seed layer. 
     
     
         19 . The method of  claim 18  wherein the conductive material provided in preparation for depositing the structural material further comprises an adhesion layer. 
     
     
         20 . The method of  claim 14  wherein the separating of the sacrificial material comprises plasma etching.