CN103091969A

CN103091969A - Optical proximity effect correction method for opposite wire ends or nearly opposite wire ends

Info

Publication number: CN103091969A
Application number: CN2011103350319A
Authority: CN
Inventors: 陈福成
Original assignee: Shanghai Hua Hong NEC Electronics Co Ltd
Current assignee: Shanghai Huahong Grace Semiconductor Manufacturing Corp
Priority date: 2011-10-28
Filing date: 2011-10-28
Publication date: 2013-05-08

Abstract

The invention discloses an optical proximity effect correction method for opposite wire ends or nearly opposite wire ends. The method comprises the following steps: 1) dividing wire ends into a plurality of sections; and 2) adjusting positions of every section along a direction perpendicular to the wire end, such that the wire ends deviate the opposite positions. According to the present invention, the opposite wire ends or the nearly opposite wire ends are divided into a plurality of the sections, and then positions of the wire end correction sections are adjusted in model-based optical proximity effect correction, wherein the wire end is subjected to a turning treatment so as to avoid a limitation on MRC of the wire end opposite direction, and reduce a wire end shortening length.

Description

Relatively or near the optical proximity correction method of relative line end

Technical field

The present invention relates to SIC (semiconductor integrated circuit) and make the field, particularly relate to relatively or near optical approach effect correction (OPC) method of relative line end.

Background technology

In the SIC (semiconductor integrated circuit) design process, for convenient wiring, straight line is preferentially selected in the capital, wherein have much and relatively or relatively (refer between line end and line end near relative line end, in the distance of X, the Y-direction minimum clearance more than or equal to the design rule place, and in the distance of the directions X minimum clearance less than 1.5 times, as shown in Figure 1).But due to the existence of optical approach effect (OPE, optical proximity effect), line end can produce very large skew, is commonly referred to as line end and shortens (line-endshortening).Consider MEEF (the mask error enhancement factor after reticle is made, mask error enhancer) effect, OPC is revising two relatively or near relative line end, the length of line end can only carried out correction to a certain degree.For example, in Fig. 2, the design load of two line end gaps is 140 nanometers, after having considered the MEEF factor, MRC (Mask Rule Checking, mask rule inspection) sets on reticle the value in the gap between two line ends must be more than or equal to 116 nanometers, line end is after revising through OPC, figure with software simulation from the lithography layout to the wafer shifts, and the analogue value that obtains two line end gaps is 218 nanometers, thereby has caused line end can not reach the length of anticipation.

Summary of the invention

The technical problem to be solved in the present invention be to provide a kind of relatively or approach the optical proximity correction method of relative line end, it can avoid the restriction of the MRC of line end relative direction, reduces the length of line end shortening.

For solving the problems of the technologies described above, of the present invention relatively or near the optical proximity correction method of relative line end, comprise step:

1) described line end is divided into multistage;

2) along the direction perpendicular to described line end, adjust every a bit of position, make described line end depart from relative position.

The perpendicular direction of the direction that described line end departs from and MRC restriction.

Every a bit of perpendicular to the amount of movement of line end direction less than or equal to 25% of live width.

When adjusting every a bit of position, can also adjust every a bit of width.Every a bit of width can greater than, be equal to or less than the width of former line end.

The present invention will be by will relatively or being divided into multistage near relative line end, then in the optical approach effect correction (Model Based OPC) based on model, desired value to line end correction fragment is adjusted, namely to the line end processing of turning round, thereby avoided the restriction of the MRC of line end relative direction, reduced the length that line end shortens.

Description of drawings

Fig. 1 is two, and between line end, the distance of directions X must be more than or equal to the minimum clearance in minimum design rule near the schematic diagram of relative line end, and less than the minimum clearance of 1.5 times.

Fig. 2 is traditional line end OPC modification method schematic diagram; Wherein, (1) is design configuration, and (2) are the revised reticle figure of OPC, and (3) are the software simulation figure.

Fig. 3 is the line end OPC modification method schematic diagram of the present embodiment; Wherein, (1) is design configuration, and (2) are that the revised reticle figure of OPC (3) is the software simulation figure.

Embodiment

Understand for technology contents of the present invention, characteristics and effect being had more specifically, existing in conjunction with illustrated embodiment, details are as follows:

As shown in Fig. 3 (1), the design load in the gap between two relative line ends is 140 nanometers, the design load of line end width is also 140 nanometers, these two line ends are divided into respectively 2 revise fragment, then, fragment 1 is moved 15 nanometers along the direction perpendicular to line end, and fragment 2 moves 15 nanometers along the direction perpendicular to line end again with respect to revising fragment 1; Same, fragment 1 ' is moved 15 nanometers along the direction perpendicular to line end, fragment 2 ' moves 15 nanometers along the direction perpendicular to line end again with respect to fragment 1 '; The position movement opposite direction of the correction fragment of two line ends.

Above-mentioned design configuration obtains the reticle figure as shown in Fig. 3 (2) after OPC revises.The value in the gap on MRC setting reticle between these two line ends must be more than or equal to 116 nanometers.

With eda software (for example, the calibre workbench software of Mentor Graphics, or the OPC Simulation software of other EDA company) figure of simulation from the reticle figure to wafer shifts, obtain the mimic diagram as shown in Fig. 3 (3), the analogue value in two line end gaps is 192 nanometers.As seen, than traditional modification method (Fig. 2), the modification method of the present embodiment has improved the degree that line end shortens to a great extent in the situation that keep original MRC constant.

Claims

1. relatively or near the optical proximity correction method of relative line end, it is characterized in that, comprise step:

1) described line end is divided into multistage;

2. method according to claim 1, is characterized in that step 2) in, the perpendicular direction of the direction that line end departs from and MRC restriction.

3. method according to claim 1, is characterized in that step 2) in, every a bit of amount of movement at the perpendicular line extreme direction is less than or equal to 25% of live width.

4. method according to claim 1, is characterized in that step 2) in, also comprise every a bit of width is adjusted.