Offset-printing method for three-dimensional printed memory
The present invention discloses an offset-printing method for a three-dimensional printed memory. The mask-patterns for different memory levels are merged onto a multi-region data-mask. At different printing steps, a wafer is offset by different values with respect to the data-mask. Accordingly, data-patterns from a same data-mask are printed into different memory levels.
1. An offset-printing method for printing at least two data-coding layers in a three-dimensional printed memory with a data-mask, comprising the steps of:
1) forming a substrate circuit on a semiconductor wafer, wherein said wafer comprises at least two adjacent dice including first and second dice;
2) forming a first memory level above said substrate circuit, including a first printing step for transferring a first mask pattern to a first data-coding layer in said first memory level, wherein an origin of said data-mask is initially aligned to an origin of said first dice at said first printing step;
3) forming a second memory level above said first memory level, including a second printing step for transferring a second mask pattern to a second data-coding layer in said second memory level, wherein said origin of said data-mask is initially aligned to an origin of said second dice at said second printing step;
wherein said first and second mask patterns are located on said data-mask.
2. The method according to claim 1 , wherein said data-mask comprises at least first and second mask-regions whose mask patterns are transferred to said first and second data-coding layers.
3. The method according to claim 2 , wherein the mask pattern of said first mask-region is transferred to said first data-coding layer in said first dice at said first printing step.
4. The method according to claim 2 , wherein the mask pattern of said second mask-region is transferred to said first data-coding layer in said second dice at said first printing step.
5. The method according to claim 2 , wherein the mask pattern of said first mask-region is transferred to said second data-coding layer in said second dice at said second printing step.
6. The method according to claim 2 , wherein the mask pattern of said second mask-region is transferred to said second data-coding layer in said first dice at said second printing step.
7. The method according to claim 2 , wherein said first memory level of said first dice stores a first data-array.
8. The method according to claim 2 , wherein said second memory level of said first dice stores a second data-array.
9. The method according to claim 2 , wherein said first memory level of said second dice stores a second data-array.
10. The method according to claim 2 , wherein said second memory level of said second dice stores a first data-array.
11. The method according to claim 1 , wherein said first printing step is photo-lithography.
12. The method according to claim 1 , wherein said second printing step is photo-lithography.
13. The method according to claim 1 , wherein said first printing step is imprint-lithography.
14. The method according to claim 1 , wherein said second printing step is imprint-lithography.