Thick metal integrated transmission line fabrication

A method for fabricating thick metal transmission line circuits, comprising the steps of:

• (a) providing a substrate having a first surface and a second surface which is parallel to the first surface;
• (b) depositing a metal plating base layer on the first surface of the substrate;
• (c) depositing a metal ground plane layer on the second surface of the substrate;
• (d) applying a photoresist layer onto the plating base layer;
• (e) providing an X-ray mask having X-ray absorbers positioned thereon in a pattern defining a transmission line circuit topology including a thick metal microstrip transmission line;
• (f) exposing the photoresist layer to X-rays from an X-ray source through the X-ray mask to make a portion of the photoresist layer dissolvable in a pattern corresponding to the transmission line circuit topology;
• (g) developing the exposed photoresist layer to remove the dissolvable portions thereof and to expose the plating base layer in areas from which the photoresist layer is removed;
• and
• (h) electroplating a metal onto the plating base layer in the areas from which the photoresist layer has been removed to form the thick metal transmission line circuit including the thick metal microstrip transmission line.

A method for fabricating thick metal transmission line circuits, comprising the steps of:

• (a) providing a substrate having a first surface and a second surface which is parallel to the first surface;
• (b) depositing a metal plating base layer on the first surface of the substrate;
• (c) depositing a metal ground plane on the second surface of the substrate;
• (d) applying a photoresist layer onto the plating base layer;
• (e) providing an X-ray mask having X-ray absorbers positioned thereon in a pattern defining a transmission line circuit topology including a band-pass filter having a plurality of conductor sections that are separated from each other by gaps;
• (f) exposing the photoresist layer to X-rays from an X-ray source through the X-ray mask to make a portion of the photoresist layer dissolvable in a pattern corresponding to the transmission line circuit topology;
• (g) developing the exposed photoresist layer to remove the dissolvable portions thereof and to expose the plating base layer in areas from which the photoresist layer is removed;
• and
• (h) electroplating a metal onto the plating base layer in the areas from which the photoresist layer has been removed to form the thick metal transmission line circuit including metal conductor sections separated from each other by gaps to form the band-pass filter.

A method for fabricating thick metal transmission line circuits, comprising the steps of:

• (a) providing a substrate having a first surface and a second surface which is parallel to the first surface;
• (b) depositing a metal plating base layer on the first surface of the substrate;
• (c) depositing a metal ground plane on the second surface of the substrate;
• (d) applying a photoresist layer onto the plating base layer;
• (e) providing an X-ray mask having X-ray absorbers positioned thereon in a pattern defining a transmission line circuit topology including a low-pass filter having alternating narrow and wide conductor sections;
• (f) exposing the photoresist layer to X-rays from an X-ray source through the X-ray mask to make a portion of the photoresist layer dissolvable in a pattern corresponding to the transmission line circuit topology;
• (g) developing the exposed photoresist layer to remove the dissolvable portions thereof and to expose the plating base layer in areas from which the photoresist layer is removed;
• and
• (h) electroplating a metal onto the plating base layer in the areas from which the photoresist layer has been removed to form the thick metal transmission line circuit including alternating narrow and wide metal conductor sections to form the low-pass filter.