Etch failure prediction based on wafer resist top loss

1. A method comprising:

determining first and second features of an integrated circuit (IC) design;

determining, prior to a mask write and to wafer print down of a resulting IC circuit corresponding to the IC design, a thickness of a resist layer of the IC design indicated by a profile of an aerial image of the IC design;

determining a threshold value according to the thickness by determining a thickness of the resist layer within a region of the IC design containing the first and second features, wherein the threshold value is determined according to the thickness within the region;

comparing, by a processor, the threshold value to a separation distance between the first and second features prior to the mask write and to wafer print down;

determining a nominal threshold value for the entire IC design, wherein the threshold value is further based on the nominal threshold; and

comparing, by the processor, each feature within the region of the IC design with the threshold value;

wherein the threshold value is a summation of the nominal threshold value and a weighted value of the thickness.

2. The method according to claim 1 , comprising:

initiating, prior to the mask write and wafer print down, a modification of a positioning of the first and/or second features based on the comparison.

3. The method according to claim 1 , comprising:

modifying the nominal threshold and/or the threshold value based on an etch failure between the first and second features in a resulting IC circuit of the IC design.

4. The method according to claim 1 , comprising:

comparing the threshold value to a second separation distance between the first feature and a third feature, the third feature being within the region.

5. The method according to claim 1 , comprising:

indicating the region as a hotspot based on the comparison.

6. An apparatus comprising:

at least one processor; and

at least one memory including computer program code for one or more programs,

the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform at least the following,

determine first and second features of an integrated circuit (IC) design;

determine, prior to a mask write and to wafer print down of a resulting IC circuit corresponding to the IC design, a thickness of a resist layer of the IC design indicated by a profile of an aerial image of the IC design;

determine a threshold value based on the thickness by determining a thickness of the resist layer within a region of the IC design containing the first and second features, wherein the threshold value is determined according to the thickness within the region;

compare the threshold value to a separation distance between the first and second features prior to the mask write and to wafer print down;

determine a nominal threshold value for the IC design, wherein the threshold value is further based on the nominal threshold; and

compare each feature within the region of the IC design with the threshold value;

wherein the threshold value is a summation of the nominal threshold value and a weighted value of the thickness.

7. The apparatus according to claim 6 , wherein the apparatus is further caused to:

initiate a modification of a positioning of the first and/or second features based on the comparison.

8. The apparatus according to claim 6 , wherein the apparatus is further caused to:

modify the nominal threshold and/or the threshold value based on an etch failure between the first and second features in a resulting IC circuit of the IC design.

9. The apparatus according to claim 6 , wherein the apparatus is further caused to:

compare the threshold value to a second separation distance between the first feature and a third feature, the third feature being within the region.

10. The apparatus according to claim 6 , wherein the apparatus is further caused to:

indicate the region as a hotspot based on the comparison.

11. The apparatus according to claim 6 , wherein the comparison is in real-time.

12. A method comprising:

determining a plurality of features in first and second window regions of an integrated circuit (IC) design;

determining, prior to a mask write and to wafer print down of a resulting IC circuit corresponding to the IC design, a first and second thickness of a resist layer for the first and second window regions, respectively, indicated by a profile of an aerial image of the IC design;

determining first and second window threshold values for the first and second window regions, respectively, based on the first and second thicknesses, respectively, and a nominal threshold value for the IC design;

determining first and second separation distances between features of the plurality of features within the first and second window regions, respectively; and

comparing, in real-time and by a processor, the first and second window threshold values to the first and second separation distances, respectively, before the mask write and wafer printing,

wherein the first and second window threshold values are summations of the nominal threshold value and a weighted value of the first and second thickness, respectively.

13. The method according to claim 12 , comprising:

initiating a modification of a positioning of at least one of the plurality features based on the comparison.

14. The method according to claim 12 , comprising:

modifying the nominal threshold, the first window threshold value, the second window threshold value, or a combination thereof, based on an etch failure between at least two of the features in the resulting IC circuit.

15. The method according to claim 12 , comprising:

indicating the first and/or second window region as a hotspot based on the comparison.