Can reduce ion and implant the shallow impurity drain domain logical operation method of shadow effect
Technical field
The present invention relates to a kind of shallow impurity drain domain logical operation method that reduces inclination angle ion implantation shadow effect of semiconductor manufacturing.
Background technology
LDD (the shallow doped-drain of lightly doped drain) produces by the domain logical operation.Carrying out LDD and Halo (halo) (claiming Pocket again) twice ion implants, it is also non-perpendicular when partial L DD and most Halo ion are implanted, but the inclination certain angle, this just might close on the photoresistance influence of masking layer on the subject wafer, thereby produces shadow effect (as Fig. 1).In general, the LDD that the domain logical operation produces is along the border (as Fig. 2) of heavy implanted layer (Plus implant layer), this makes needs strict more heavy implanted layer layout design rules in some special domains, as introducing the restriction of m1 and m2 minimum dimension among Fig. 3, be used to draw back and close on the masking layer photoresistance to the distance of device channel, reduce the inclination angle ion and implant shadow effect (for example in some 0.15 micron logic processing procedure, the minimum dimension of regulation m1 and m2 is 0.4 micron).And in processing procedure, also need photoresistance (PR) thickness of attenuate LDD as far as possible, the precision of control CD (the key size of critical dimension) and alignment overlay (stack is aimed at).
Summary of the invention
A kind of shallow impurity drain domain logical operation method that the inclination angle ion is implanted shadow effect that reduces provided by the invention when having reduced shadow effect, has tightened chip area, has guaranteed processing quality, has improved integrated level simultaneously.
In order to achieve the above object, the invention provides a kind of shallow impurity drain domain logical operation method that ion is implanted shadow effect that reduces, comprise following steps:
Step 1, determine the channel region of metal-oxide semiconductor (MOS) (MOS) pipe of grid and active area (ACT) crossover;
Step 2, regional every limit that step 1 the is determined big a that rises, wherein a can adjust according to concrete processing procedure ability;
Step 3, in the zone that step 2 is determined, carry out ion and implant, generate LDD.
Utilize domain logical operation provided by the invention, m1 and m2 minimum dimension no longer directly are subjected to the restriction of processing procedure ability during layout design, and the unique and parameter processing procedure direct correlation becomes a, and this can tighten chip area.M1 and m2 are less than a generally speaking, this means by the N type or the P type LDD layer (NLDD/PLDD layer) of domain logical operation generation provided by the invention and understand the adjacent P+/N+ heavily doped region (Plus) of some covering, because LDD still is that the degree of depth all can not show a candle to heavily doped region (Plus) from concentration in general logic processing procedure, so can not produce any influence to heavily doped region.And the injection of LDD/Halo ion has only the part of next-door neighbour's metal-oxide-semiconductor raceway groove just can the metal-oxide-semiconductor characteristic to be exerted an influence, so than the logical operation of traditional LDD domain, the ion implantation region territory that this logical operation reduces can not produce any effect to the metal-oxide-semiconductor characteristic.
Description of drawings
Fig. 1 is the schematic diagram that the inclination angle ion is implanted shadow effect in the background technology;
Fig. 2 is the zone boundary schematic diagram of the LDD that traditional domain logical operation produces in the background technology;
Fig. 3 is a layout design rules relevant with shadow effect in the background technology;
Fig. 4 is a kind of area schematic that the inclination angle ion is implanted the LDD that the shallow impurity drain domain logical operation method of shadow effect produces that reduces provided by the invention.
Embodiment
Followingly specify better embodiment of the present invention according to Fig. 4:
As shown in Figure 4, the invention provides a kind of shallow impurity drain domain logical operation method that the inclination angle ion is implanted shadow effect that reduces, comprise following steps:
Step 1, determine the channel region of metal-oxide semiconductor (MOS) (MOS) pipe of grid and the district's crossover of having chance with;
Step 2, regional every limit that step 1 the is determined big a that rises, in some 0.15 micron logic processing procedure, the scope that can select a value is 0.3-0.5um;
Step 3, in the zone that step 2 is determined, carry out ion and implant, generate LDD.
Utilize logic processing procedure provided by the invention, m1 and m2 minimum dimension no longer directly are subjected to the restriction of processing procedure ability during layout design, tighten chip area thereby can suitably lower the requirement.Unique and the parameter processing procedure direct correlation becomes a, and (as in 0.15 micron system, be subjected to the processing procedure capabilities limits, m1 and m2 minimum dimension are 0.4 micron.But after having used this novel domain logical operation, m1 and m2 can drop to 0.25 micron, only needing that a is set at 0.4 micron gets final product) m1 and m2 be less than a generally speaking, this means by the N type or the P type LDD layer (NLDD/PLDD layer) of domain logical operation generation provided by the invention and understand the adjacent P+/N+ heavily doped region (Plus) of some covering, because LDD still is that the degree of depth all can not show a candle to heavily doped region (Plus) from concentration in general logic processing procedure, so can not produce any influence to heavily doped region.And the injection of LDD/Halo ion has only the part of next-door neighbour's metal-oxide-semiconductor raceway groove just can the metal-oxide-semiconductor characteristic to be exerted an influence, so than the logical operation of traditional LDD domain, the ion implantation region territory that this logical operation reduces can not produce any effect to the metal-oxide-semiconductor characteristic.