Method for etching and for forming a contact hole using thereof

Abstract

To provide a method for forming an etching structure without difficulty to control the manufacturing conditions, and with a minute dimension exceeding the limit of exposure, while suppressing increase of manufacturing processes and increasing of manufacturing cost. Solution: With regard to a method for forming a structure formed by etching which is typified by a contact hole in the semiconductor such as a thin film transistor and to a method for manufacturing a display device using the structure, and more specifically relates to the method for the structure formed by etching which is typified by the contact hole formed using the technology of reflow in dissolving and to the method for manufacturing a thin film transistor substrate for the display device using the structure, the method for etching includes at least, a process for forming an organic mask having a first opening portion and a second opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched, and a process for forming a transformed organic mask by dissolving the organic mask in contact with organic solvent and reflowing.

1 . A method for etching at least including:
 a process for forming an organic mask having a first opening portion in which a first etching structure is formed and a second opening portion in which a second etching structure provided with a upper etching structure is formed, by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched, and   a process for forming a transformed organic mask by dissolving the organic mask in contact with organic solvent and reflowing.   
     
     
         2 . A method for etching according to  claim 1 , wherein the organic film is formed with at least thickness of the film being formed so as to have a plurality of stages. 
     
     
         3 . A method for etching according to  claim 1 , wherein the organic film formed with a plurality of stages in the film thickness has a film thickness area in a vicinity of at least one of the first opening portion and the second opening portion, thinner than other areas. 
     
     
         4 . A method for etching according to  claim 1 , wherein the process for forming the organic mask further forms a first opening portion and a second opening portion having a diameter larger than that of the first opening portion. 
     
     
         5 . A method for etching according to  claim 1 , wherein the process for forming the transformed organic mask includes a process in which the organic mask is dissolved in contact with organic solvent, re-flown, and then a part of the organic mask runs and sags along a side wall of the first etching structure and along a side wall of the upper etching structure of the second etching structure in a way that the re-flown organic mask fills both of the side wall and at least a bottom of the first etching structure, while leaving a bottom of the upper etching structure unfilled. 
     
     
         6 . A method for etching according to  claim 1 , wherein the process for forming the transformed organic mask includes a process in which the organic mask is dissolved in contact with organic solvent, re-flown, and then a part of the organic mask runs and sags along a side wall of the first etching structure in a way that the re-flown organic mask fills the side wall and at least a bottom of the first etching structure while leaving a portion unfilled in the upper etching structure. 
     
     
         7 . A method for etching according to  claim 1 , wherein the process for forming the transformed organic mask includes a process in which through reflow in dissolving, a part of the organic mask runs and sags along a side wall of only the first etching structure in a way that the organic mask fills the side wall and at least a bottom of the first etching structure while the re-flown organic mask reaches a vicinity area of the upper end of the upper etching structure, leaving inside the upper etching structure unfilled. 
     
     
         8 . A method for etching according to  claim 1 , wherein the transformed organic mask fills the one of the first opening portion or the second opening portion, and leaves the other unfilled. 
     
     
         9 . A method for etching according to  claim 1 , wherein the method includes a process for etching the constituent part to be etched using the organic mask which becomes the transformed organic mask successively, and a process for selectively etching the constituent part to be etched just beneath of the first opening portion and the second opening portion. 
     
     
         10 . A method for etching according to  claim 9 , wherein the selectively etching is an optionality of the first opening portion and the second opening portion. 
     
     
         11 . A method for etching according to  claim 9 , wherein the selectively etching is based on a difference of etching amount in the first opening portion and the second opening portion. 
     
     
         12 . A method for etching according to  claim 9 , wherein the selectively etching is based on a difference of etching depth in the first opening portion and the second opening portion. 
     
     
         13 . A method for etching according to  claim 9 , wherein the selectively etching is based on a difference of etching damage in the first opening portion and the second opening portion. 
     
     
         14 . A method for etching according to  claim 9 , wherein the first opening portion and the second opening portion are different in the planar dimensions. 
     
     
         15 . A method for etching according to  claim 1 , wherein the method, after forming the transformed organic mask in accordance with the first etching structure and the upper etching structure in the second etching structure, further includes a process for selectively etching the constituent part to be etched to a depth of a second final target level which is deeper than a first final target level without any etching damages to a bottom of the first etching structure while using the transformed organic mask, thereby forming a lower etching structure provided just below the upper etching structure in the second etching structure,
 the first etching structure having the first final target level of depth, and   the upper etching structure and the lower etching structure defining the second etching structure having the second final target level of depth.   
     
     
         16 . A method for etching according to  claim 1 , wherein the method, after forming the transformed organic mask in accordance with the first etching structure and the upper etching structure in the second etching structure, further includes a process for selectively etching the constituent part to be etched to a depth of a second final target level which is deeper than a first final target level without any etching damages to a bottom of the first etching structure while using the transformed organic mask, thereby forming a lower etching structure provided just below the upper etching structure in the second etching structure and with a horizontal dimension smaller than that of the upper etching structure,
 the first etching structure having the first final target level of depth, and the upper etching structure and lower etching structure defining the second etching structure having the second final target level of depth and with forward tapered in a staircase pattern.   
     
     
         17 . A method for etching which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask by dissolving the organic mask in contact with organic solvent, reflowing and at least filling a bottom of the first etching structure with a part of re-flown organic mask while leaving a upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, provided with the upper etching structure and a lower etching structure, by forming the lower etching structure lying just below the upper etching structure while selectively etching the constituent part to be etched to a depth of the second final target level which is deeper than that of the first final target level without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         18 . A method for etching according to  claim 17 , wherein the method includes a process for forming a transformed organic mask through reflow in dissolving in which the reflow in dissolving fills at least the bottom of the first etching structure while leaving the upper etching structure unfilled. 
     
     
         19 . A method for etching which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion having a dimension larger than that of the first opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure and along a side wall of a upper etching structure of the second etching structure, so that the re-flown organic mask fills both of the side walls and at least a bottom of the first etching structure while leaving a bottom of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth and with forward tapered in a staircase pattern, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure and having a horizontal dimension smaller than that of the upper etching structure in the second etching structure, while selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         20 . A method for etching according to  claim 19 , wherein the horizontal dimension of the lower etching structure in the second etching structure is smaller than that of the upper etching structure, by the quantity corresponding to approximately two times of the thickness formed in the horizontal direction of the transformed organic mask after reflow in dissolving runs and sags along the side wall of the upper etching structure. 
     
     
         21 . A method for etching which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         22 . A method for etching according to  claim 21 , wherein the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof. 
     
     
         23 . A method for etching which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion, and having a thickness in the vicinity of the second opening portion thinner than other portions by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         24 . A method for etching according to  claim 23 , wherein the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof. 
     
     
         25 . A method for etching which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion, and having a thickness in the vicinity of the second opening portion thinner than other portions by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for removing only a portion with thinner film thickness in the vicinity of the second opening portion,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of only the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, though the re-flown organic mask reaches a vicinity area of the upper end of the upper etching structure, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         26 . A method for etching according to  claim 25 , wherein the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof. 
     
     
         27 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion in which a first etching structure is formed and a second opening portion in which a second etching structure provided with a upper etching structure is formed, by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched, and   a process for forming a transformed organic mask by dissolving the organic mask in contact with organic solvent and reflowing.   
     
     
         28 . A method for forming a contact hole according to  claim 27 , wherein
 the organic film is formed with at least thickness of the film being formed so as to have a plurality of stages.   
     
     
         29 . A method for forming a contact hole according to  claim 27 , wherein
 the organic film formed with a plurality of stages in the film thickness has a film thickness area in a vicinity of at least one of the first opening portion and the second opening portion, thinner than other areas.   
     
     
         30 . A method for forming a contact hole according to  claim 27 , wherein the process for forming the organic mask further forms a first opening portion and a second opening portion having a diameter larger than that of the first opening portion. 
     
     
         31 . A method for forming a contact hole according to  claim 27 , wherein the process for forming the transformed organic mask includes a process in which the organic mask is dissolved in contact with organic solvent, re-flown, and then a part of the organic mask runs and sags along a side wall of the first etching structure and along a side wall of a upper etching structure of the second etching structure in a way that the re-flown organic mask fills both of the side wall and at least a bottom of the first etching structure, while leaving a bottom of the upper etching, structure unfilled. 
     
     
         32 . A method for forming a contact hole according to  claim 27 , wherein the process for forming the transformed organic mask includes a process in which the organic mask is dissolved in contact with organic solvent, re-flown, and then a part of the organic mask runs and sags along a side wall of the first etching structure in a way that the re-flown organic mask fills the side wall and at least a bottom of the first etching structure while leaving a portion unfilled in the upper etching structure. 
     
     
         33 . A method for forming a contact hole according to  claim 27 , wherein
 the process for forming the transformed organic mask includes a process in which through reflow in dissolving, a part of the organic mask runs and sags along a side wall of only the first etching structure in a way that the organic mask fills the side wall and at least a bottom of the first etching structure while the re-flown organic mask reaches a vicinity area of the upper end of the upper etching structure, leaving inside the upper etching structure unfilled.   
     
     
         34 . A method for forming a contact hole according to  claim 27 , wherein
 the method includes a process for etching the constituent part to be etched using the organic mask which becomes the transformed organic mask successively, and a process for selectively etching the constituent part to be etched just beneath of the first opening portion and the second opening portion.   
     
     
         35 . A method for forming a contact hole according to  claim 27 , wherein the method includes a process for etching the constituent part to be etched using the organic mask which becomes the transformed organic mask successively, and a process for selectively etching the constituent part to be etched just beneath of the first opening portion and the second opening portion. 
     
     
         36 . A method for forming a contact hole according to  claim 35 , wherein the selectively etching is an optionality of the first opening portion and the second opening portion. 
     
     
         37 . A method for forming a contact hole according to  claim 35 , wherein the selectively etching is based on a difference of etching amount in the first opening portion and the second opening portion. 
     
     
         38 . A method for forming a contact hole according to  claim 35 , wherein the selectively etching is based on a difference of etching depth in the first opening portion and the second opening portion. 
     
     
         39 . A method for forming a contact hole according to  claim 35 , wherein the selectively etching is based on a difference of etching damage in the first opening portion and the second opening portion. 
     
     
         40 . A method for forming a contact hole according to  claim 35 , wherein
 the first opening portion and the second opening portion are different in the planar dimensions.   
     
     
         41 . A method for forming a contact hole according to  claim 27 , wherein
 the method, after forming the transformed organic mask in accordance with the first etching structure and the upper etching structure in the second etching structure, further includes a process for selectively etching the constituent part to be etched to a depth of a second final target level which is deeper than a first final target level without any etching damages to a bottom of the first etching structure while using the transformed organic mask, thereby forming a lower etching structure provided just below the upper etching structure in the second etching structure,   the first etching structure having the first final target level of depth, and   the upper etching structure and the lower etching structure defining the second etching structure having the second final target level of depth.   
     
     
         42 . A method for forming a contact hole according to  claim 27 , wherein
 the method, after forming the transformed organic mask in accordance with the first etching structure and the upper etching structure in the second etching structure, further includes a process for selectively etching the constituent part to be etched to a-depth of a second final target level which is deeper than a first final target level without any etching damages to a bottom of the first etching structure while using the transformed organic mask, thereby forming a lower etching structure provided just below the upper etching structure in the second etching structure and with a horizontal dimension smaller than that of the upper etching structure,   the first etching structure having the first final target level of depth, and   the upper etching structure and lower etching structure defining the second etching structure having the second final target level of depth and with forward tapered in a staircase pattern.   
     
     
         43 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask by dissolving the organic mask in contact with organic solvent, reflowing and at least filling a bottom of the first etching structure with a part of re-flown organic mask while leaving a upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, provided with the upper etching structure and a lower etching structure, by forming the lower etching structure lying just below the upper etching structure while selectively etching the constituent part to be etched to a depth of the second final target level which is deeper than that of the first final target level without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         44 . A method for forming a contact hole according to  claim 43 , wherein the method includes a process that reflow in dissolving fills at least the bottom of the first etching structure while leaving the upper etching structure unfilled. 
     
     
         45 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion having a dimension larger than that of the first opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched, a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure and along a side wall of a upper etching structure of the second etching structure, so that the re-flown organic mask fills both of the side walls and at least a bottom of the first etching structure while leaving a bottom of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth and with forward tapered in a staircase pattern, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure and having a horizontal dimension smaller than that of the upper etching structure in the second etching structure, while selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         46 . A method for forming a contact hole according to  claim 45 , wherein the horizontal dimension of the lower etching structure in the second etching structure is smaller than that of the upper etching structure, by the quantity corresponding to approximately two times of the thickness formed in the horizontal direction of the transformed organic mask after reflow in dissolving runs and sags along the side wall of the upper etching structure. 
     
     
         47 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         48 . A method for forming a contact hole according to  claim 47 , wherein the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof. 
     
     
         49 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion, and having a thickness in the vicinity of the second opening portion thinner than other portions by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         50 . A method for forming a contact hole according to  claim 49 , wherein
 the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof.   
     
     
         51 . A method for forming a contact hole which includes:
 a process for forming an organic mask having a first opening portion and a second opening portion, and having a thickness in the vicinity of the second opening portion thinner than other portions by patterning an organic film which includes either one of an organic film and a film with the addition of organic solvent and is located on a constituent part to be etched,   a process for forming a first etching structure with a first final target level of depth and is located below the first opening portion, and for forming a upper etching structure with a depth equal or similar to the first final target level of depth and is located below the second opening portion, by selectively etching the constituent part to be etched using the organic mask,   a process for removing only a portion with thinner film thickness in the vicinity of the second opening portion, a process for forming a transformed organic mask in a way that by dissolving the organic mask in contact with organic solvent and reflowing, a part of the organic mask is running and sagging along a side wall of only the first etching structure, so that the re-flown organic mask fills the side wall of the first etching structure and at least a bottom thereof while leaving inside of the upper etching structure unfilled, though the re-flown organic mask reaches a vicinity area of the upper end of the upper etching structure, and   a process for forming the first etching structure with the first final target level of depth and a second etching structure with a second final target level of depth, the second etching structure providing with the upper etching structure and a lower etching structure lying just below the upper etching structure in the second etching structure, by selectively etching the constituent part to be etched to the depth of the second final target level which is deeper than that of the first final target level, without any etching damages to the bottom of the first etching structure using the transformed organic mask.   
     
     
         52 . A method for forming a contact hole according to  claim 51 , wherein the method includes a process for forming an unfilled transformed organic mask inside the upper etching structure through reflow in dissolving while filling the side wall of the first etching structure and at least the bottom thereof.