Method of manufacturing structure having anodized parts

Abstract

A method of manufacturing a structure having anodized parts includes: forming a bottom metal pattern with a dielectric layer thereon on a substrate, in which the dielectric layer has an opening exposing the bottom metal pattern; forming a semiconductor layer to cover the dielectric layer; forming a first metal layer on the semiconductor layer; forming a second metal layer on the first metal layer; forming a mask layer on the second metal layer to expose a portion of a top surface of the second metal layer; etching the second metal layer through the mask layer until a top surface of the first metal layer is exposed, in which an etch selectivity of the second metal layer and the first metal layer is greater than 2.0; anodizing the first metal layer through the mask layer to form an anodized segment; and removing the mask layer.

What is claimed is: 
     
         1 . A method of manufacturing a structure having anodized parts, comprising:
 forming a bottom metal pattern with a dielectric layer thereon on a substrate, wherein the dielectric layer has at least one opening exposing the bottom metal pattern;   forming a semiconductor layer to cover the dielectric layer;   forming a first metal layer on the semiconductor layer;   forming a second metal layer on the first metal layer;   forming a mask layer on the second metal layer to expose a portion of a top surface of the second metal layer;   etching the second metal layer through the mask layer until a top surface of the first metal layer is exposed, wherein an etch selectivity of the second metal layer and the first metal layer is greater than 2.0;   anodizing the first metal layer through the mask layer to form an anodized segment; and   removing the mask layer after the anodizing.   
     
     
         2 . The method of  claim 1 , wherein an atomic ratio of aluminum in the first metal layer is greater than 50%. 
     
     
         3 . The method of  claim 2 , wherein the first metal layer further contains at least one rare earth element. 
     
     
         4 . The method of  claim 2 , wherein the first metal layer further contains zirconium, silicon, or tungsten. 
     
     
         5 . The method of  claim 2 , wherein the first metal layer further contains valve metals. 
     
     
         6 . The method of  claim 1 , wherein an atomic ratio of copper in the second metal layer is greater than 40%. 
     
     
         7 . The method of  claim 1 , wherein the second metal layer comprises a first sub-layer and a second sub-layer stacked on the first sub-layer. 
     
     
         8 . The method of  claim 7 , wherein the first sub-layer contains molybdenum, titanium, or an alloy thereof. 
     
     
         9 . The method of  claim 7 , wherein an atomic ratio of copper in the second sub-layer is greater than 40%. 
     
     
         10 . The method of  claim 1 , wherein the etching is performed by a dry etching process. 
     
     
         11 . The method of  claim 1 , wherein the etching is performed by a wet etching process. 
     
     
         12 . The method of  claim 1 , wherein the anodizing is performed by using an electrolyte containing a content of water less than 45 wt %, and the electrolyte has a pH value between pH5 and pH8. 
     
     
         13 . The method of  claim 1 , wherein the anodizing is performed at a temperature under 20° C. 
     
     
         14 . The method of  claim 1 , wherein the anodizing is performed to reach a termination voltage less than 500 Volt. 
     
     
         15 . The method of  claim 1 , wherein the anodizing is performed until the anodized segment reaches a side of the first metal layer facing the substrate. 
     
     
         16 . The method of  claim 15 , wherein the anodized segment serves as a channel protect structure above the dielectric layer, and the anodized first metal layer further comprises two unanodized segments electrically isolated from each other by the anodized segment and serving as drain and source electrodes respectively. 
     
     
         17 . The method of  claim 1 , wherein a thickness of an unanodized part of the anodized first metal layer is greater than 1/10 of a thickness of the bottom metal pattern before the anodizing. 
     
     
         18 . The method of  claim 1 , wherein the mask layer comprises a first photoresist zone and a second photoresist zone thicker than the first photoresist zone, and the method further comprises:
 etching a combination of the first metal layer and second metal layer through the mask layer to form a metal pattern before the etching the second metal layer; and   removing the first photoresist zone while remaining the second photoresist zone, wherein the etching the second metal layer is performed through the remaining second photoresist zone.   
     
     
         19 . The method of  claim 1 , wherein the mask layer comprises a first photoresist zone and a second photoresist zone thicker than the first photoresist zone, and the method further comprises:
 removing the first photoresist zone while remaining the second photoresist zone after the anodizing; and   etching a combination of the first metal layer and second metal layer through the remaining second photoresist zone to form a metal pattern.   
     
     
         20 . The method of  claim 1 , wherein the forming the bottom metal pattern with the dielectric layer comprises:
 forming a bottom metal layer on the substrate;   forming another mask layer on the bottom metal layer, wherein the another mask layer comprises a first photoresist zone and a second photoresist zone thicker than the first photoresist zone;   etching the bottom metal layer through the another mask layer to form the bottom metal pattern;   removing the first photoresist zone while remaining the second photoresist zone;   anodizing the bottom metal pattern through the remaining second photoresist zone to form the dielectric layer; and   removing the remaining second photoresist zone.   
     
     
         21 . The method of  claim 20 , wherein an atomic ratio of aluminum in the bottom metal layer is greater than 50%. 
     
     
         22 . The method of  claim 20 , wherein a thickness of an unanodized part of the anodized bottom metal pattern is greater than 1/10 of a thickness of the bottom metal pattern before the anodizing. 
     
     
         23 . The method of  claim 1 , wherein the forming the bottom metal pattern with the dielectric layer comprises:
 forming a bottom metal layer on the substrate;   forming a first mask layer on the bottom metal layer;   etching the bottom metal layer through the first mask layer to form the bottom metal pattern;   removing the first mask layer;   forming a second mask layer on the bottom metal pattern;   anodizing the bottom metal pattern through the second mask layer to form the dielectric layer; and   removing the second mask layer.   
     
     
         24 . The method of  claim 23 , wherein an atomic ratio of aluminum in the bottom metal layer is greater than 50%. 
     
     
         25 . The method of  claim 23 , wherein a thickness of an unanodized part of the anodized bottom metal pattern is greater than 1/10 of a thickness of the bottom metal pattern before the anodizing. 
     
     
         26 . The method of  claim 1 , wherein the forming the bottom metal pattern with the dielectric layer comprises:
 forming a bottom metal layer on the substrate;   forming a first mask layer on the bottom metal layer;   etching the bottom metal layer through the first mask layer to form the bottom metal pattern;   removing the first mask layer;   depositing a dielectric film on the bottom metal pattern;   forming a second mask layer on the dielectric film;   etching the dielectric film through the second mask layer to form the dielectric layer; and   removing the second mask layer.