CN105702548A

CN105702548A - Shielding device and plasma processing apparatus with same

Info

Publication number: CN105702548A
Application number: CN201410686564.5A
Authority: CN
Inventors: 林哲全
Original assignee: Advanced Micro Fabrication Equipment Inc Shanghai
Current assignee: Medium and Micro Semiconductor Equipment (Shanghai) Co., Ltd.
Priority date: 2014-11-25
Filing date: 2014-11-25
Publication date: 2016-06-22
Anticipated expiration: 2034-11-25
Also published as: TW201631618A; CN105702548B; TWI590292B

Abstract

The invention discloses a shielding device used for selectively preventing charged particles from passing through holes from plasmas. The shielding device includes a first shielding plate arranged in a reaction chamber, a conductive assembly, a measuring assembly and a control assembly; a plurality of first through holes are formed in the first shielding plate; the first shielding plate is provided with a conductive material; a direct-current bias voltage is applied to the conductive material; a plasma distribution area between the first shielding plate in the reaction chamber and a plasma source is provided with a surface exposed to the plasmas; the measuring assembly is used for measuring the current of the plasmas absorbed by the surface of the conductive assembly; and the control assembly calculates and controls the bias voltage value and polarity of the direct-current bias voltage according to a measuring result of the measuring assembly. With the shielding device adopted, the direct-current bias voltage can be accurately controlled, so that the charged particles can be prevented from arriving at the surface of a substrate, so that damage to the surface of the substrate due to the charged particles can be avoided.

Description

Screening arrangement and there is the plasma processing apparatus of this screening arrangement

Technical field

The present invention relates to semiconductor processing equipment, particularly to a kind of for optionally preventing belt charged particle is passed through from plasma screening arrangement and the plasma processing apparatus with this screening arrangement。

Background technology

Currently, plasma processing apparatus, as the device performing the kinds of processes such as film forming, etching on a semiconductor die, is widely used in the technical field that semiconductor device manufactures。In plasma processing apparatus, make the action of plasma of reacting gas on a semiconductor die, and perform corresponding Cement Composite Treated by Plasma。In general, plasma comprises charged particle such as cation and electronics and the free radical as neutral particle。In some plasma-treating technologies, process mainly by radical pair semiconductor chip。Photoresist as removed photoresist process requirement free radical and semiconductor chip surface reacts。If charged particle arrives semiconductor chip, then can produce negative reciprocal action with semiconductor chip and cause the damage of chip semiconductor-on-insulator assembly, it is desirable to less charged particle is accumulated in chip surface。

Chinese patent CN100573830C provides and a kind of optionally only makes the selection that free radical passes through pass through unit, this selection has the insulation board of more than 2 that are formed with multiple pass through openings portion by cell location, stagger in the position making this pass through openings portion, owing in general cation can be subject to the bias voltage attraction of pedestal generation linearly to move, therefore when staggering in the pass through openings portion of two plates, collide the entity part of lower plate by the cation of upper plate pass through openings and lower plate cannot be passed, but free radical is owing to being that neutral not being biased voltage attracts and can move at random, still can by the pass through openings of lower plate, it is possible to optionally make free radical pass through from plasma。But, when using highdensity plasma to improve the efficiency of the Cement Composite Treated by Plasma using free radical, cationic density also improves therewith, therefore, cation is also improved by the probability of above-mentioned two plate, and film on semiconductor chip is it is possible to because cation is damaged。

Chinese patent CN101919030B provides another kind of solution, and it is by having the plasma confinement plate of multiple free radical entrance hole electrical ground to discharge, thus stoping the charged particle in plasma by free radical entrance hole。But this method still cannot be completely eliminated leakage current, and charged particle can not be thus completely shielded。

Accordingly, it is desirable to provide a kind of screening arrangement that optionally preventing belt charged particle is passed through from plasma is to improve drawbacks described above。

Summary of the invention

Present invention is primarily targeted at the defect overcoming prior art, it is provided that a kind of charged particle screening arrangement carrying out preventing belt charged particle arrival substrate surface by accurately controlling Dc bias, to effectively reduce the damage to substrate surface semiconductor device。

For reaching above-mentioned purpose, the present invention provides a kind of for optionally preventing belt charged particle is passed through from plasma produced by the plasma source of plasma processing apparatus screening arrangement。Described screening arrangement includes: the first barricade, is arranged in the reaction chamber of described plasma processing apparatus, is formed with multiple first through hole, and described first barricade has conductive material, and described conductive material applies a Dc bias；Conductive component, is arranged at the plasma distribution region in described reaction chamber, between described first barricade and described plasma source and has the surface being exposed to plasma；Measure assembly, the electric current of the plasma that the surface for measuring described conductive component absorbs；And control assembly, calculate and control bias value and the polarity of described Dc bias according to the measurement result of described measurement assembly。

Preferably, described screening arrangement also includes the secondary shielding plate be arrangeding in parallel with described first barricade, forms multiple second through hole in described secondary shielding plate, and the plurality of second through hole is not overlapping with the plurality of first through hole or partly overlaps。

Preferably, described secondary shielding plate has on conductive material and described conductive material and applies described Dc bias。

Preferably, described conductive component is arranged at multiple positions in described plasma distribution region, and described control assembly calculates according to multiple measurement results that described measurement assembly obtains and controls bias value and the polarity of described Dc bias。

Preferably, described conductive component is attached on described first barricade。

Preferably, the polarity of Dc bias described in the Polarity Control of the plasma current that described control assembly arrives according to described measurement component detection, calculate and control the bias value of described Dc bias according to the current value of described plasma current。

Preferably, when the electric current that described plasma measured by described measurement assembly is positive-ion current, it is just that described control assembly controls the polarity of described Dc bias；When the electric current that described plasma measured by described measurement assembly is negatron electric current, it is negative that described control assembly controls the polarity of described Dc bias。

Preferably, described first barricade is that conductive material is made or at non-conducting material surface-coated conductive coating。

Preferably, described first barricade and secondary shielding plate are that conductive material is made or at non-conducting material surface-coated conductive coating。

According to a further aspect in the invention, additionally provide a kind of plasma processing apparatus, comprising: plasma source；Reaction chamber, it includes the pedestal for loading substrate；And above-mentioned screening arrangement, the barricade of described screening arrangement is positioned at the top of the described pedestal of described reaction chamber。

The beneficial effects of the present invention is the characteristic by detecting the electric current that plasma produces and determine to apply magnitude of voltage and the polarity of Dc bias on the shield plates, it is thus possible to control Dc bias exactly to carry out preventing belt charged particle arrival substrate surface, to effectively reduce the damage to substrate surface semiconductor device。

Accompanying drawing explanation

Fig. 1 is the schematic diagram of the plasma processing apparatus with screening arrangement of one embodiment of the invention；

Fig. 2 is the schematic diagram of the plasma processing apparatus with screening arrangement of another embodiment of the present invention。

Detailed description of the invention

For making present disclosure clearly understandable, below in conjunction with Figure of description, present disclosure is described further。Certainly the invention is not limited in this specific embodiment, the general replacement known by those skilled in the art is also covered by protection scope of the present invention。

Fig. 1～Fig. 2 shows the plasma treatment appts that numerous embodiments of the present invention provides。It should be understood that it is merely exemplary, it is possible to include less or more form assembly, maybe the arrangement of this composition assembly is likely to different from diagram。

Embodiment one

Refer to Fig. 1, the plasma processing apparatus of the present embodiment includes reaction chamber 10, plasma generator 11 and screening arrangement。The pedestal 12 for clamping pending substrate W it is provided with bottom reaction chamber 10；Process gas is excited as plasma supply internal to reaction chamber 10 as remote plasma source by remote plasma generator 11；Screening arrangement for from plasma optionally preventing belt charged particle pass through。Other modes such as the plasma source of the present invention is not limited to remote plasma generator, it would however also be possible to employ inductive (ICP), microwave generate plasma in reaction chamber 10。

Screening arrangement has: top shielding plate 20 (the first barricade), conductive component 30, measures assembly 40 and controls assembly 50。Wherein top shielding plate 20 is arranged in reaction chamber 10 top of pedestal 12, and it can be fixed by a support component (not shown)。Top shielding plate 20 has conductive material 22。Additionally, barricade 20 is also formed multiple first through hole 21, so that the free radical in plasma passes through substrate W。Top shielding plate 20 can itself be made of an electrically conducting material, or at one layer of conductive coating of non-conducting material surface-coated。As it can be seen, the conductive material 22 of barricade 20 connects DC source 60, this DC source 60 applies Dc bias to barricade 20 so that the charged particle in plasma cannot pass barricade 20。Difference according to plasma process process, in plasma, the attribute of charged particle and kinetic energy distribution also can be different accordingly, if therefore only apply the Dc bias of fixed voltage value and polarity to the conductive material 22 of barricade 20, then it is more likely to produce the excessive too small or opposite polarity situation of DC bias value, causes charged particle to occur through the situation of barricade 20。In order to monitor the characteristic of charged particle in reaction chamber chamber piasma in real time and provide corresponding feedback, the screening arrangement of the present invention have also been devised sensory package and controls assembly。Wherein, sensory package includes conductive component 30 and measures assembly 40。Conductive component 30 is arranged at the plasma distribution region inside reaction chamber 10, between the first barricade 20 and plasma source 11, and having the surface being exposed to plasma, thus bombardment is arrived the charged particle on conductive component 30 surface and is formed the electric current of plasma on the surface of conductive component。Conductive component 30 is such as connected with the measurement assembly 40 outside reaction chamber 10 by wire。In the present embodiment, measure assembly 40 and include the galvanometer of ground connection, the positive negativity of the electric current of conductive component 30 surface plasma can be measured, when the majority on bombardment induced conductivity assembly 30 surface is electronics, it is negative that amperometric measurement goes out the current polarity of plasma, when the majority on bombardment induced conductivity assembly 30 surface is cation, amperometric measurement goes out the current polarity of plasma for just。Additionally, galvanometer also can measure the size of plasma current certainly。Measuring assembly 40 can also be other forms, such as the combination etc. of resistance Yu voltameter, as long as the size of current of the plasma of conductive component 30 Surface absorption can be measured and positive and negative。Control assembly 50 and be connected with measuring assembly 40, calculate and control bias value and the polarity of the Dc bias that DC source 60 is applied on barricade 20 conductive material 22 according to the measurement result measuring assembly 40。Specifically, control the assembly 50 polarity according to the Polarity Control Dc bias of the electric current of plasma, in the present embodiment, when the electric current that plasma measured by measurement assembly 40 is positive-ion current, the charged particle illustrated in plasma mostly is cation, control assembly 50 and control the polarity of Dc bias for just, the polarity of cation is identical with the polarity of the Dc bias applied to top barricade 20, therefore, this cation is subject to repulsive force from top shielding plate 20 and is dislodged with the direction away from substrate W；When the electric current that plasma measured by measurement assembly 40 is negatron electric current, the charged particle illustrated in plasma mostly is electronics, it is negative that control assembly 50 controls the polarity of Dc bias, the polarity of electronics is identical with the polarity of the Dc bias applied to top barricade 20, therefore, this electronics is subject to repulsive force from top shielding plate 20 equally and is dislodged with the direction away from substrate W。By the Dc bias applied on top shielding plate 20 is designed as and plasma current identical polar, it is possible to shield or expel the most charged particles forming plasma current to avoid its traverse top shielding plate 20。On the other hand, controlling assembly 50, to control Dc bias according to the size of measured plasma current be suitable magnitude of voltage, so that all charged particles all cannot pass barricade 20。Being positive-ion current for measurement to the electric current of plasma, if the positive bias applied is too small, cation cannot be dislodged completely, and then can pass barricade；If the positive bias applied is excessive, although cation can be dislodged, but the captivation of the electronics in plasma is also more big, so as to be adsorbed on barricade surface, and then it is likely to through barricade, it is thus desirable to control assembly 50, the size of bias value is controlled, it is ensured that only the free radical of neutral particle is through barricade 20 with to substrate W process, and avoids the charged particle impact on substrate W semiconductor-on-insulator assembly function。

Conductive component 30 can be arranged on any position in plasma distribution region, such as the port of export of plasma source 11, i.e. reaction chamber 10 top open part。Preferably, conductive component 30 is to be sticked on the upper surface of top shielding plate 20 as shown in the figure, such conductive component 30 is identical with the characteristic of the plasma that top shielding plate 20 receives, measure the actual electric current reflecting the plasma that top shielding plate 20 surface absorbs of measurement result that assembly 40 obtains, and eliminate once measure the component detection electric current to conductive component 30 surface, that is to say and mean that all charged particles all expel from barricade 20, therefore control result more accurate。In addition, although conductive component 30 is only one in the present embodiment, but may be used without multiple conductive component 30 in other embodiments, it is arranged on multiple positions in plasma distribution region, such as it is attached at marginal position and the center of barricade 20, then measure assembly 40 and be obtained in that multiple measurement result, control assembly 50 multiple measurement results are calculated (as averaging or other complicated calculations) to obtain the attribute of charged particle in plasma more accurately, be achieved in the control of more accurate Dc bias。

Embodiment two

Refer to Fig. 2, the present embodiment and embodiment one are distinctive in that, screening arrangement also includes the underlying shield plate 23 (secondary shielding plate) being positioned at above pedestal 12 and top shielding plate 20 be arranged in parallel。Underlying shield plate 23 has multiple second through hole 24, the position of the second through hole 24 and the first through hole 21 is not overlapping or partly overlaps, namely the first through hole 21 and the second through hole 24 is set in the way of being formed without straight line connection, so when charged particle will collide with the entity part of underlying shield plate 23 after the first through hole 21, it is possible to prevent charged particle from arriving substrate W through secondary shielding plate 23 further。The size and dimension of the first through hole and the second through hole can arbitrarily set, and the shape size of each through hole in same barricade also can be different, and the present invention is not any limitation as。

Underlying shield plate 23 has conductive material 25 equally, and this conductive material 25 is also connected with DC source 60 and applies Dc bias。Underlying shield plate 23 can itself be made of an electrically conducting material, or non-conducting material surface-coated conductive coating。Owing to underlying shield plate 23 is also connected with DC source 60, control assembly 50 calculates, according to the measurement result measuring assembly 40, the Dc bias controlling to obtain and can be applied on underlying shield plate 23 by DC source 60 equally, therefore further enhance the repulsive interaction to charged particle, play better blocking effect。

In sum, screening arrangement proposed by the invention and plasma processing apparatus, the attribute of charged particle in plasma is obtained by detecting the characteristic of the electric current that plasma produces, and then accurately control to apply magnitude of voltage and the polarity of Dc bias on the shield plates, arriving substrate surface with preventing belt charged particle through barricade, the present invention can effectively reduce the damage to substrate。

Although the present invention discloses as above with preferred embodiment; right described many embodiments are illustrated only for the purposes of explanation; it is not limited to the present invention; those skilled in the art can do some changes and retouching without departing from the spirit and scope of the present invention, and the protection domain that the present invention advocates should be as the criterion with described in claims。

Claims

1. a screening arrangement, is applied to plasma processing apparatus, for from plasma produced by the plasma source of this plasma processing apparatus optionally preventing belt charged particle pass through, it is characterised in that described screening arrangement includes:

First barricade, is arranged in the reaction chamber of described plasma processing apparatus, is formed with multiple first through hole, and described first barricade has conductive material, and described conductive material applies a Dc bias；

Conductive component, is arranged at the plasma distribution region in described reaction chamber, between described first barricade and described plasma source and has the surface being exposed to plasma；

Measure assembly, the electric current of the plasma that the surface for measuring described conductive component absorbs；And

Control assembly, calculate and control bias value and the polarity of described Dc bias according to the measurement result of described measurement assembly。

2. screening arrangement according to claim 1, it is characterized in that, also including the secondary shielding plate be arrangeding in parallel with described first barricade, form multiple second through hole in described secondary shielding plate, the plurality of second through hole is not overlapping with the plurality of first through hole or partly overlaps。

3. screening arrangement according to claim 2, it is characterised in that described secondary shielding plate has on conductive material and described conductive material and applies described Dc bias。

4. screening arrangement according to claim 1, it is characterized in that, described conductive component is arranged at multiple positions in described plasma distribution region, and described control assembly calculates according to multiple measurement results that described measurement assembly obtains and controls bias value and the polarity of described Dc bias。

5. screening arrangement according to claim 1, it is characterised in that described conductive component is attached on described first barricade。

6. screening arrangement according to claim 1, it is characterized in that, the polarity of Dc bias described in the Polarity Control of the plasma current that described control assembly arrives according to described measurement component detection, calculates and controls the bias value of described Dc bias according to the current value of described plasma current。

7. screening arrangement according to claim 6, it is characterised in that when the electric current that described plasma measured by described measurement assembly is positive-ion current, it is just that described control assembly controls the polarity of described Dc bias；When the electric current that described plasma measured by described measurement assembly is negatron electric current, it is negative that described control assembly controls the polarity of described Dc bias。

8. screening arrangement according to claim 1, it is characterised in that described first barricade is that conductive material is made or at non-conducting material surface-coated conductive coating。

9. screening arrangement according to claim 3, it is characterised in that described first barricade and secondary shielding plate are that conductive material is made or at non-conducting material surface-coated conductive coating。

10. a plasma processing apparatus, it is characterised in that including:

Plasma source；

Reaction chamber, it includes the pedestal for loading substrate；And

Screening arrangement as described in any one of claim 1～9, the barricade of described screening arrangement is positioned at the top of the described pedestal of described reaction chamber。