Offset-printing method of multi-bit three-dimensional offset-printed memory

Abstract

The invention provides an offset-printing method of a multi-bit three-dimensional offset-printed memory. Data mask patterns corresponding to different digital bits are combined onto a same data mask.In different offset-printing steps, the offset of wafers relative to the data mask is different. Thus, data patterns from the same data mask are offset-printed into data input membranes with differentdigital bits.

Description

technical field [0001] This invention relates to the field of integrated circuit memories and, more particularly, to mask-programmed read-only memories (mask-ROMs). Background technique [0002] Three-dimensional mask-programmed read-only memory (3D-MPROM) is an ideal medium for mass publishing. US Patent 5,835,396 discloses a 3D-MPROM. Such as figure 1 As shown, 3D-MPROM is a monolithic integrated circuit, which includes a semiconductor substrate 0 and a three-dimensional stack 10 stacked on the substrate. The three-dimensional stack 10 contains M (M≥2) storage layers (such as 10A, 10B) stacked on each other. Each storage layer (such as 10A) contains multiple top address lines (such as 2a), bottom address lines (such as 1a) and storage elements (such as 5aa). Each storage element stores n (n≥1) bits of data. The storage layer (such as 16A, 16B) is coupled with the substrate 0 through contact via holes (such as 1av, 1'av). The substrate circuit 0X in the substrate 0 co...

AI Technical Summary

Problems solved by technology

At the 22nm node, the cost of a data mask is $250,000, and the cost of a set of x8x2 3D-MPROM data masks (including 16 data masks) is as high as $4 million

Such a high data mask cost will greatly limit the wide application of 3D-MPROM

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