A kind of device and using method thereof of eliminating wafer sample surface charge effect
Technical field
The present invention relates to the Apparatus and method for that surface analysis is used in the SIC (semiconductor integrated circuit) manufacturing field, particularly eliminate the Apparatus and method for that the disk surfaces electric charge is used in the SIC (semiconductor integrated circuit) during surface analysis.
Background technology
Development along with semicon industry, the Auger electron spectrometer of using as surface analysis (hereinafter to be referred as Auger), because it is to the high susceptibility of sample surfaces 70A left and right sides element, being applied in the semicon industry more and more widely is in the analysis of especially surface contamination aspect.
But the charge effect of sample surfaces material is more and more serious to the influence of Auger sample.
When for example being used for the Auger analysis, charge effect has just produced analysis result and has seriously influenced.
Auger utilizes electron beam in the sample surfaces motion process, and resulting Auger electron spectroscopy is done analysis.Because every kind of unit have feature Auger electron energy separately, so can be used to determine contained chemical constitution.
But the existence of charge effect makes the power spectrum drift, even spectral line distorts, so just can not the contained composition in correct analysis surface, had a strong impact on the correctness of analysis result.
Traditional sample stage structure as shown in Figure 1 and Figure 2, wherein 1 is pedestal, 2 is overcoat, sample is placed on the pedestal 1, overcoat 2 card is pressed on it, second fixed sample first can lead away the electric charge on sample surface.But owing to be the outer ring, so the charge effect that can eliminate is very limited.
And existing usefulness solves the Auger sample surface charge effect method of analyzing influential problem respectively there is shortcoming.
The method that the Auger sample surface charge effect is eliminated in common being used at present is as follows:
At sample surfaces plating Pt; At the foraminate aluminium foil of sample surfaces wrap; Make charge compensation with low-energy ion at sample surfaces.
But above method but all has shortcoming separately.
Can cause damage and Pt signal also can influence the collection of other feeble signals too by force to sample surfaces at sample surfaces plating Pt; Success ratio in the foraminate foil samples preparation of sample surfaces wrap is very low; Need specific installation and make charge compensation at sample surfaces, the cost costliness with low-energy example.
Therefore, when carrying out surface analysis in the actual production, press for a kind of not impact analysis, simple to operation, the apparatus and method that do not need the elimination sample charge effect of extra specific installation with low cost.
Summary of the invention
At the problem that occurs in the prior art, the present invention proposes a kind of apparatus and method of novel elimination sample charge effect.
The device that the present invention proposes is made of three parts:
Metal grill, sample stage and two cover bolt assemblies constitute.
Wherein, metal grill has two parts to constitute, and a part is the round-meshed sheet metals in both sides, and another part is that middle metal grill constitutes, and wherein the diameter of the circular hole on the sheet metal is greater than the screw diameter of above-mentioned bolt, less than the diameter of bolt head.Middle metal grill by be parallel to each other, horizontal and vertical two groups of wire nettings that bonding jumper is connected to form arranged in a uniform, the hole of this wire netting is rectangular, and is evenly distributed, size is identical.
Sample stage is made of the brace table of pedestal and support disk.
The pedestal of sample stage and existing pedestal are basic identical, respectively are connected with a derby that supports the projection that disk to be analyzed uses at the right and left of pedestal, and as the brace table of the support disk on the sample stage, what disk can level is placed on it.For bolt can pass through, have a manhole on the derby of this projection, the diameter of this round tube hole is also greater than the screw diameter of above-mentioned bolt, less than the diameter of bolt head.
The position of two through hole is aimed at mutually with metal grill, and promptly the spacing of two circular holes on two through hole spacing and the metal grill is identical on the pedestal, and two through hole is arranged in one on the footpath on the pedestal.
Every cover bolt assembly is made of bolt, first, second two springs and nut.
Metal grill is positioned over sample stage top, and the two through hole on the metal grill is overlapped with through hole on the sample stage.
From top to bottom, bolt is inserted in the through hole of metal grill both sides, and passes first spring, puts into the through hole on the sample stage, is inserted in second spring afterwards, nut is screwed in the bolt bottom, to withstand the lower end of second spring again.
Before placing disk, will push up on second bolt, make second length of spring compressed, thereby make metal grill can upwards lift certain distance, thereby the disk sheet can be put on the sample stage under the metal grill.
And first spring will make the metal grill certain position of upspringing, and when needs are led away electric charge, bolt be pressed down, first length of spring compressed, and bolt moves downward and drives bolt head and press down metal grill thereupon, and metal grill is pressed on the disk surfaces.Metal grill is contacted with disk and since pedestal can be in the Auger board ground connection, thereby metal grill is by bolt ground connection.So just can lead away the electric charge on the disk surfaces.But after the elimination electric charge is finished, remove the pressure on the bolt.Grid is under the restoring force effect of spring, and the segment distance that moves upward breaks away from and the contacting of disk, thereby in test process, do not contact with disk, thereby also the test result formation of disk is not influenced.
In addition, because horizontal and vertical bonding jumper is equally distributed on the metal grill, so, this metal grill can also be assisted as the coordinate diagram of disk and seek wafer pattern.
By this device, and simple to operate, do not need extra equipment, do not need extra operation yet.
Description of drawings
Fig. 1 is the structural drawing of the platform that uses in the prior art;
Fig. 2 is the vertical view of the platform that uses in the prior art;
Fig. 3 is the structural drawing of embodiment 1 device;
Fig. 4 is the vertical view of embodiment 1 device;
Wherein, 1 is the pedestal of sample stage, and 2 is lid, and 3 is the brace table of sample stage, and 40 is bolt, and 41 is nut, and 42 is first spring, and 43 is second spring, and 5 is metal grill.
Embodiment
The present invention is described further below in conjunction with Figure of description and embodiment.
Specific embodiment
The device that present embodiment proposes is made of three parts, referring to Fig. 3:
Metal grill 5, the pedestal 1 of sample stage and bolt assembly constitute.
Sample stage is made of the brace table of pedestal and support disk.
Pedestal and existing pedestal are basic identical, respectively are connected with a derby that supports the projection that disk to be analyzed uses at the right and left of pedestal, as the brace table that supports sample.For bolt can pass through, have a manhole on this brace table, the diameter of this round tube hole is also greater than the screw diameter of above-mentioned bolt, and less than the diameter of bolt head, the diameter of this through hole is also greater than the screw diameter of above-mentioned bolt 40, less than the diameter of bolt head.So that bolt 40 can pass through this through hole.The position and the metal grill of two through hole are corresponding, and promptly the spacing of two circular holes on two through hole spacing and the metal grill is identical on the pedestal, and two through hole is arranged on the diameter on the pedestal.
Wherein, metal grill 5 has two parts to constitute: a part is the round-meshed sheet metals in both sides, and a part is middle metal grill in addition.Wherein the diameter of the circular hole on the sheet metal is greater than the screw diameter of above-mentioned bolt, less than the diameter of bolt head.Middle metal grill by be parallel to each other, horizontal and vertical two groups of wire nettings that bonding jumper is connected to form arranged in a uniform, the hole of this wire netting is rectangular, and is evenly distributed, size is identical referring to Fig. 4.
For bolt 40 can pass through, also have a manhole on the sample stage equally, the diameter of this round tube hole is also greater than the screw diameter of above-mentioned bolt, less than the diameter of bolt head.
Other parts of pedestal and existing pedestal are basic identical.
Bolt assembly is made of bolt 40, first spring 42 and second spring 43 and nut 41.
Metal grill 5 is positioned over sample stage top, and the two through hole on the metal grill is overlapped with through hole on pedestal and the sample stage.
Bolt 40 is penetrated through hole on the metal grill, be inserted in first spring 42 again.This spring is depressed metal grill with the metal grill certain altitude of upspringing when needs are led away electric charge, metal grill 40 is contacted with disk, leads away the electric charge on the disk.But after the elimination electric charge is finished, remove the pressure on the metal grill.Grid moves upward under the restoring force effect of spring, break away from and the contacting of disk, thereby in the test process, also the test result of disk not being constituted influences.
Bolt 40 is penetrated through hole on the sample stage from top to bottom, and second spring 43 is inserted in from the bolt bottom, again nut is screwed in the bolt bottom, to be used for withstanding the spring bottom.
Before placing disk, will push up on second bolt, make second length of spring compressed, thereby make metal grill can upwards lift certain distance, thereby the disk sheet can be put on the sample stage under the metal grill.
And first spring will make the metal grill certain position of upspringing, and when needs are led away electric charge, bolt be pressed down, first length of spring compressed, and bolt moves downward and drives bolt head and press down metal grill thereupon, and metal grill is pressed on the disk surfaces.Metal grill is contacted with disk and since pedestal can be in the Auger board ground connection, thereby metal grill is by bolt ground connection ground connection.So just can lead away the electric charge on the disk surfaces.But after the elimination electric charge is finished, remove the pressure on the bolt.Grid is under the restoring force effect of spring, and the segment distance that moves upward breaks away from and the contacting of disk, thereby in test process, do not contact with disk, thereby also the test result formation of disk is not influenced.
So by present embodiment, simple to operate, do not need extra equipment, do not need extra operation yet and can realize location easily zone to be analyzed on the disk.