CN102768968A

CN102768968A - Method for detecting diffusivity of wellblock implantation ions in different concentrations

Info

Publication number: CN102768968A
Application number: CN2012102258023A
Authority: CN
Inventors: 范荣伟; 倪棋梁; 龙吟; 王恺; 陈宏璘
Original assignee: Shanghai Huali Microelectronics Corp
Current assignee: Shanghai Huali Microelectronics Corp
Priority date: 2012-07-03
Filing date: 2012-07-03
Publication date: 2012-11-07
Anticipated expiration: 2032-07-03
Also published as: CN102768968B

Abstract

The invention relates to a method for detecting the diffusivity of wellblock implantation ions in different concentrations, and the method includes the following steps: step 1, establishing a test module, wherein active areas on the module include a P wellblock and an N wellblock separated through shallow trench isolation; step 2, simulating the process structure, and forming tungsten connection holes in the wellblock; step 3; performing ion implantation, only implantation of ions in different concentrations into the P wellblock and the N wellblock; and step 4, scanning the test module to obtain a continuous-tone image of the tungsten connection holes. The method provides references for wellblock optimization of the semiconductor device, provides guarantee for yield improvement, and is simple and easy to carry out.

Description

Detect the wellblock and inject the method for ion diffusivity under the variable concentrations condition

Technical field

The invention belongs to semiconductor applications, relate to a kind of method that detects the ions diffusion ability, relate in particular to a kind of method that ion diffusivity under the variable concentrations condition is injected in the wellblock that detects.

Background technology

The quality of semiconductor device wellblock plays a key effect to semiconductor device, when device accomplishes that 55nm is following, the control of wellblock is even more important.There is several factors can the wellblock of semiconductor device be exerted an influence, like the dosage of injection ion, the degree of depth, angle, and ion self diffusion etc.And owing to lack the effective appraisal procedure to ion self diffusivity, so be difficult to control its influence to device.

Be injected into the ion of wellblock, repair in the thermal annealing process, understand along ruined lattice diffusion, and be horizontal proliferation mostly at follow-up lattice.And the horizontal proliferation of ion is very big to device performance harm, under heat effect, is diffused into the p type wells district such as the ion of N type wellblock, can have a strong impact on the performance of NMOSFET device.Its ions diffusion zone will produce electric leakage with PMOSFET.

Be directed against the horizontal proliferation of the ion under the different ions concentration conditions of wellblock at present; Mostly through wafer acceptance testing (wafer acceptance test; WAT) and testing electrical property carry out; Because follow-up many processing procedures all can exert an influence to WAT and testing electrical property result, be difficult to accurately measure its lateral diffusion-capability, and extended the process cycle time.

Therefore those skilled in the art is devoted to develop a kind of method that can effectively detect wellblock injection ion diffusivity under the variable concentrations condition.

Summary of the invention

In view of above-mentioned the problems of the prior art, technical problem to be solved by this invention is that existing technology lacks the method that ion diffusivity under the variable concentrations condition is injected in the wellblock that effectively detects.

A kind of method that ion diffusivity under the variable concentrations condition is injected in the wellblock that detects of the present invention may further comprise the steps:

Step 1 is set up test module, and the behaviour area on the said module comprises P wellblock and the N wellblock that is separated by shallow trench isolation;

Step 2 is simulated the processing procedure structure, and the tungsten connecting hole of wellblock is set;

Step 3 is carried out ion and is injected, and only carries out the variable concentrations ion injection of said P wellblock or N wellblock;

Step 4 scans test module, obtains the continuous-tone image of tungsten connecting hole.

In a preferred embodiments of invention, the size of said behaviour area is 20umx50um.

In another preferred embodiments of invention, the bottom width of said shallow trench isolation is 160 ~ 250nm.

In another preferred embodiments of invention, only carry out said N wellblock variable concentrations ion in the said step 3 and inject, if the bright then ions diffusion of the tungsten connecting hole of NMOSFET is to the N wellblock in the said step 4; If the tungsten connecting hole of NMOSFET is gloomy then ion is not diffused into the N wellblock in the said step 4.

In another preferred embodiments of invention, applying electronic harness defects scanner scans test module in the said step 4.

In another preferred embodiments of invention, also comprise step 5, thereby the bottom width of shallow trench isolation and the continuous-tone image of said tungsten connecting hole are compared the diffusivity that obtains ion.

The present invention simulates device architecture in the actual processing procedure through setting up test module, and injects the condition of ion according to required adjustment.Applying electronic harness defects scanner is checked then; Lateral diffusion-capability according to test module and scanning result measuring and calculating wellblock ion; Effectively the lateral diffusion-capability of wellblock ion under the measuring and calculating different ions concentration conditions provides powerful support for for the semiconductor device processing procedure provides.The present invention is that method is simple.

Description of drawings

Fig. 1 is the flow chart of embodiments of the invention;

Fig. 2 a is the tungsten connecting hole brightness sketch map that does not receive the ions diffusion influence of N wellblock;

Fig. 2 b is the tungsten connecting hole brightness sketch map for influenced by N wellblock ions diffusion.

Embodiment

Inject the method for ion diffusivity under the variable concentrations condition in the detection wellblock of embodiments of the invention, may further comprise the steps:

Step 1 is set up test module.On module, marking off the behaviour area (AA) of the certain area of different groups, is 20umx50um such as size.On these AA, divide P wellblock and N wellblock at interval, separate by shallow trench isolation (STI) between P well and the N well, the bottom width of STI is done different windows on actual processing procedure basis.Such as the actual STI width of hypothesis is 250nm, can make ten windows of 160 to 250 five equilibrium so respectively, is Y nm such as the actual STI width of hypothesis, can make the window of the five equilibrium of Y-40 to Y+50 so respectively.This kind test module can be laid on the wafer as required.Confirm under other condition prerequisites, change and want to calculate the condition that the wellblock ion injects.

Step 2 is simulated actual processing procedure structure, the tungsten connecting hole of wellblock is set, and suitably simplifies.Distribute and structure such as being simplified to the device that mainly contains P wellblock and N wellblock composition.The purpose that structure is simplified is the interference of removing other factors.

Step 3 is adjusted the wellblock ion implanting conditions as required.Detect the spread condition under the N well ion variable concentrations condition like needs, ion is omitted in the P wellblock inject, the ion of variable concentrations is injected in the N wellblock.

Step 4, applying electronic harness defects scanner is checked.When processing procedure was gone to the tungsten connecting hole, applying electronic harness defects scanner (E-beam) scanned test module.Shown in Fig. 2 a and 2b, wherein 1 is the N wellblock, and 11 is the tungsten connecting hole of N wellblock, and 2 is shallow trench isolation, and 3 is the P wellblock, and 31 is the tungsten connecting hole of P wellblock.Under the normal condition; Shown in Fig. 2 a; The tungsten connecting hole 31 of NMOSFET is gloomy under E-beam positive load condition, and the tungsten connecting hole 11 of PMOSFET is for bright, if still P well ions diffusion is to the N well area; Shown in Fig. 2 b, then can be that the tungsten connecting hole 31 of NMOSFET produces electric leakage (Leakage) and becomes bright.

Step 5, according to because this variation, and the STI bottom width arranged of integrating step 1 just can finally obtain the ability of N wellblock ion horizontal proliferation under the different ions concentration conditions.

Embodiments of the invention are simulated device architecture in the actual processing procedure through setting up test module, and inject the condition of ion according to required adjustment.Applying electronic harness defects scanner is checked then; Lateral diffusion-capability according to test module and scanning result measuring and calculating wellblock ion; Thereby can effectively detect the wellblock and inject the effective ways that the ion lateral diffusion-capability changes with ion concentration; And then be the methodology that provides of process window optimization and on-line monitoring, for the online manufacturing of semiconductor and yield provide safeguard.The present invention is that method is simple.

This method can be applied to the window that the wellblock ion injects the ion concentration condition, thus optimize device performance.Whether the leakage problem of the device after measuring and calculating is optimized has obtained effective solution.

More than specific embodiment of the present invention is described in detail, but it is just as example, the present invention is not restricted to the specific embodiment of above description.To those skilled in the art, any equivalent modifications that the present invention is carried out with substitute also all among category of the present invention.Therefore, not breaking away from impartial conversion and the modification of being done under the spirit and scope of the present invention, all should contain within the scope of the invention.

Claims

1. one kind is detected the method that ion diffusivity under the variable concentrations condition is injected in the wellblock, it is characterized in that, may further comprise the steps:

2. the method for ion diffusivity under the variable concentrations condition is injected in detection as claimed in claim 1 wellblock, it is characterized in that the size of said behaviour area is 20umx50um.

3. the method for ion diffusivity under the variable concentrations condition is injected in detection as claimed in claim 2 wellblock, it is characterized in that the bottom width of said shallow trench isolation is 160 ~ 250nm.

4. the method for ion diffusivity under the variable concentrations condition is injected in detection as claimed in claim 1 wellblock; It is characterized in that; Only carry out said N wellblock variable concentrations ion in the said step 3 and inject, if the bright then ions diffusion of the tungsten connecting hole of NMOSFET is to the N wellblock in the said step 4; If the tungsten connecting hole of NMOSFET is gloomy then ion is not diffused into the N wellblock in the said step 4.

5. the method for ion diffusivity under the variable concentrations condition is injected in detection as claimed in claim 1 wellblock, it is characterized in that applying electronic harness defects scanner scans test module in the said step 4.

6. the method for ion diffusivity under the variable concentrations condition is injected in detection as claimed in claim 1 wellblock; It is characterized in that; Also comprise step 5, thereby the bottom width of shallow trench isolation and the continuous-tone image of said tungsten connecting hole are compared the diffusivity that obtains ion.