Mandrel for electroform filter including uniform pores

Abstract

A mandrel, suitable for use when producing an electroform metal structure including, for example, a filter, includes a conductive material layer. A plurality of first photoresist pegs is located in a first area of the conductive material layer. Each of the plurality of first photoresist pegs includes a first diameter and a first center-to-center spacing relative to each other. A plurality of second photoresist pegs is located in a second area of the conductive material layer. Each of the plurality of second photoresist pegs includes a second diameter and a second center-to-center spacing. The first diameter is greater than the second diameter and the first center-to-center spacing is greater than the second center-to-center spacing.

1 . A mandrel, comprising:
 a conductive material layer;   a plurality of first photoresist pegs located in a first area of the conductive material layer, each of the plurality of first photoresist pegs having a first diameter and a first center-to-center spacing relative to each other; and   a plurality of second photoresist pegs located in a second area of the conductive material layer, each of the plurality of second photoresist pegs having a second diameter and a second center-to-center spacing relative to each other, wherein the first diameter is greater than the second diameter and the first center-to-center spacing is greater than the second center-to-center spacing.   
     
     
         2 . The mandrel of  claim 1 , each of the plurality of first photoresist pegs having a first edge-to-edge spacing, each of the plurality of second photoresist pegs having a second edge-to-edge spacing, wherein the first edge-to-edge spacing is approximately equivalent to the second edge-to-edge spacing. 
     
     
         3 . The mandrel of  claim 1 , wherein the first diameter is greater than 10 times the first edge-to-edge spacing. 
     
     
         4 . The mandrel of  claim 1 , further comprising:
 a plurality of third photoresist pegs, each of the plurality of third photoresist pegs having a third diameter and a third center-to-center spacing relative to each other, wherein the third diameter is not equal to the first diameter and is not equal to the second diameter, and the third center-to-center spacing is not equal to the first center-to-center spacing and is not equal to the second center-to-center spacing.   
     
     
         5 . The mandrel of  claim 1 , wherein the plurality of first photoresist pegs is arranged in staggered rows. 
     
     
         6 . The mandrel of  claim 1 , wherein the plurality of second photoresist pegs is arranged in staggered rows. 
     
     
         7 . The mandrel of  claim 1 , further comprising:
 a photoresist barrier that defines individual segments of the mandrel.   
     
     
         8 . The mandrel of  claim 1 , further comprising:
 a photoresist border that surrounds the plurality of first photoresist pegs and the plurality of second photoresist pegs.   
     
     
         9 . The mandrel of  claim 8 , further comprising:
 a margin located between the photoresist border and an edge of the mandrel.   
     
     
         10 . The mandrel of  claim 9 , wherein the margin includes the conductive material layer. 
     
     
         11 . The mandrel of  claim 10 , wherein the margin includes a plurality of photoresist pegs that is similar in size and edge to edge spacing when compared to the second plurality of photoresist pegs.