CN102387655A - Lower electrode for plasma equipment and plasma equipment - Google Patents

Abstract

The invention provides a lower electrode for plasma equipment and the plasma equipment which comprise a base and an insulation layer; the insulation layer is arranged on the top surface of the base; and the equivalent capacitance of the insulation layer in a thickness direction has a distribution trend that: the equivalent capacitance of the insulation layer along the radial direction of the insulation layer is unequal, so that the distribution of the energy of plasma on the radial direction of the insulation layer is adjusted, the distribution of ion energy on the surface of a processed workpiece on the insulation layer along the radial direction of the insulation layer meets process requirements. Consequently, the lower electrode for the plasma equipment and the plasma equipment can improve the processing performance of the plasma equipment.

Description

The bottom electrode and the plasma apparatus that are used for plasma apparatus

Technical field

The present invention relates to a kind of bottom electrode and plasma apparatus that is used for plasma apparatus.

Background technology

Progress along with plasma technique; Plasma technique has expanded to field of solar energy from traditional semiconductor and micromechanics field; And gradually to other field development; This makes the competition between the plasma apparatus exploitation enterprise be growing more intense, thereby impels equipment development enterprise constantly to innovate, and article on plasma body equipment is transformed or improved.

Through years of development; Person skilled has been developed polytype plasma apparatus; Like capacitance coupling plasma (CCP) equipment, inductively coupled plasma (ICP) equipment and Ecr plasma (ECR) equipment, these plasma apparatus are applied to the manufacturing of integrated circuit (IC), microelectromechanical systems (MEMS), light-emitting diode (LED) and solar cell.

See also Fig. 1, be a kind of structure diagram of plasma apparatus.This device comprisesreaction chamber 4,bottom electrode 1, inductance-coupledcoil 3,adaptation 6,7 andpower supply 5,8.The top ofreaction chamber 4 and bottom are provided withmedium window 9 and followingmedium window 10 respectively.Bottom electrode 1 is located at the inside ofreaction chamber 4 and near followingmedium window 10 positions,bottom electrode 1 is connected withpower supply 8 through adaptation 7.Inductance-coupledcoil 3 is located at the top ofmedium window 9, and is connected withpower supply 5 through adaptation 6.Inductance-coupledcoil 3 forms plasma with the process gas ionization in thereaction chamber 4, and action of plasma is in the surface of workpiece to be machined 2.Workpiece to be machined 2 (like wafer) is placed on the top ofbottom electrode 1, and is supported bybottom electrode 1.

See also Fig. 2, be a kind of sectional view of bottom electrode.This bottom electrode comprises pedestal 11, insulating barrier 12 and electrostatic attraction electrode 13, and insulating barrier 12 is arranged on the top of pedestal 11, and electrostatic attraction electrode 13 is wrapped up by insulating barrier 12, and is connected with DC power supply, and pedestal 11 is connected with radio-frequency power supply.After electrostatic attraction electrode 13 and DC power supply are connected, can produce the Coulomb force between electrostatic attraction electrode 13 and the workpiece to be machined 2, workpiece to be machined 2 is fixed on the surface ofbottom electrode 1 by the Coulomb force.

The operation principle of above-mentioned plasma apparatus is following: inductance-coupledcoil 3 is with the process gas ionization ofreaction chamber 4 and form plasma, and the action of plasma of generation is in workpiece to be machined 2 surfaces.When thepower supply 8 that connects pedestal 11 is radio-frequency power supply; The surface of workpiece to be machined 2 can form radio frequency plasma sheath layer; Under the effect of radio frequency plasma sheath layer; Workpiece to be machined 2 surfaces produce the negative automatic bias (hereinafter to be referred as back bias voltage) of direct current, and this back bias voltage forms the voltage drop of radio frequency sheath layer with the potential difference of the plasma that is positioned at workpiece to be machined 2 tops.When the size of workpiece to be machined 2 and machining accuracy (like the uniformity of conductor width) hour, the ion energy characteristic of workpiece to be machined 2 surperficial zoness of different and the difference of distribution situation are less, can satisfy requirement on machining accuracy basically.

Yet along with the competition and the development of technology in market, the size of workpiece to be machined 2 constantly increases, and integrated level is also increasingly high.When the diameter of workpiece to be machined 2 surpasses 300mm, requirement on machining accuracy when 65nm is following; Because the influence of air-flow, temperature and the plasma self-characteristic on workpiece to be machined 2 surfaces; Make the ion energy characteristic and the distribution situation on workpiece to be machined 2 surfaces can not satisfy technological requirement, and then cause the processing technology of plasma apparatus to meet design requirement.In addition; In the machining process of plasma apparatus; Can there be load (loading) effect between the center of workpiece to be machined 2 and the edge; Make the ion energy characteristic and the distribution situation on workpiece to be machined 2 surfaces can not satisfy technological requirement, and then cause the processing technology of plasma apparatus to meet design requirement.

Summary of the invention

The technical problem that the present invention will solve is exactly the above-mentioned defective that exists to plasma apparatus; A kind of bottom electrode that is used for plasma apparatus is provided; It can be adjusted the radio frequency sheath layer voltage drop on workpiece to be machined surface; Make the ion energy characteristic and the distribution situation on workpiece to be machined surface reach technological requirement, to satisfy large scale, high-precision processing request.

The technical scheme that is adopted that solves the problems of the technologies described above provides a kind of bottom electrode that is used for plasma apparatus; Comprise pedestal and insulating barrier; Said insulating barrier is arranged on the end face of said pedestal; The equivalent capacity of said insulating barrier on its thickness direction has following distribution trend: promptly, along the radial direction of said insulating barrier, the equivalent capacity of said insulating barrier differs in size; With the distribution of the above energy of plasma of radial direction of being adjusted in said insulating barrier, thereby make the ion energy on the workpiece to be machined surface that places on the insulating barrier satisfy technological requirement along the distribution of the radial direction of said insulating barrier.

Wherein, said insulating barrier is one-body molded by the same media material, and different at the thickness in the radial direction of said insulating barrier, or one-body molded by the different dielectric material of dielectric constant.

Wherein, said insulating barrier is to be combined by the different insulating element of a plurality of equivalent capacitys.

Wherein, said a plurality of insulating element is the fixed insulation parts.

Wherein, at least one in said a plurality of insulating element is adjustable insulating element.

Wherein, said fixed insulation parts are to be processed or processed by the different dielectric material of dielectric constant by the same media material.

Wherein, said adjustable insulating element comprises the fixed bed and the layer that goes up and down, and said up-downs layer is positioned at the below of said fixed bed and is connected with elevating mechanism, said up-down layer by elevating mechanism away from or near said fixed bed.

Wherein, when said insulating barrier adopted a plurality of said adjustable insulating element, the up-down layer of said a plurality of adjustable insulating elements was driven or is driven by each self-corresponding elevating mechanism respectively by same said elevating mechanism.

Wherein, said fixed bed is processed by dielectric material, and the said layer that goes up and down is processed by the material that electric conducting material or dielectric material or electric conducting material and dielectric material mix.

The present invention also provides a kind of plasma apparatus; Comprise processing chamber and be arranged on the bottom electrode in the said processing chamber; Said bottom electrode adopts described bottom electrode provided by the invention, so that place the ion energy on the workpiece to be machined surface on the insulating barrier to satisfy technological requirement along the distribution of the radial direction of said insulating barrier.

The present invention has following beneficial effect:

The bottom electrode that is used for plasma apparatus provided by the invention makes the zones of different on plane, said insulating barrier place have different equivalent capacitys at its thickness direction.Regulate the back bias voltage on workpiece to be machined surface, corresponding region through the equivalent capacity that changes the insulating barrier zones of different; Thereby change the radio frequency sheath layer voltage drop on workpiece to be machined surface; Ion energy characteristic and distribution situation to eliminate the workpiece to be machined surface that causes because of the energy of plasma on workpiece to be machined surface is different can't satisfy the defective of technological requirement, and then make workpiece to be machined obtain the ideal technology result.Therefore; The bottom electrode that is used for plasma apparatus provided by the invention can change the ion energy characteristic and the distribution situation on workpiece to be machined surface, makes the processing technology of plasma apparatus can reach large scale, high-precision technological requirement and obtain the ideal technology result.Similarly; Plasma apparatus provided by the invention has adopted above-mentioned bottom electrode; Radio frequency sheath layer voltage drop to the workpiece to be machined surface regulated; Make the energy of plasma characteristic and the distribution situation on workpiece to be machined surface reach technological requirement, thereby make the processing technology of plasma apparatus can reach large scale, high-precision technological requirement and obtain the ideal technology result.

Description of drawings

Fig. 1 is the structure diagram of inductively coupled plasma equipment;

Fig. 2 is the sectional view that has the bottom electrode of electrostatic chuck;

Fig. 3 is the sectional view of bottom electrode among first embodiment;

Fig. 4 is the sectional view of bottom electrode among second embodiment; And

Fig. 5 is the sectional view of the 3rd embodiment bottom electrode.

Embodiment

For making those skilled in the art understand technical scheme of the present invention better, bottom electrode and the plasma apparatus that is used for plasma apparatus provided by the invention is described in detail below in conjunction with accompanying drawing.

The machining accuracy of plasma apparatus is by the ion energy characteristic and the distribution situation decision on workpiece to be machined surface, and ion energy characteristic and distribution situation depend on the radio frequency sheath layer voltage drop on workpiece to be machined surface.The radio frequency sheath layer voltage drop on workpiece to be machined surface is meant the current potential and the potential difference between the plasma above the workpiece to be machined of workpiece to be machined.Therefore, the plasma characteristics and the distribution situation on workpiece to be machined surface are not only depended in the radio frequency sheath layer voltage drop on workpiece to be machined surface, also depend on the automatic bias on workpiece to be machined surface.The present invention changes the radio frequency sheath layer voltage drop on workpiece to be machined surface through the automatic bias that changes the workpiece to be machined surface, and then changes the ion energy characteristic and the distribution situation on workpiece to be machined surface.The mechanism of production of the automatic bias on workpiece to be machined surface is following: when bottom electrode was connected with radio-frequency power supply, the surface of workpiece to be machined can form radio frequency plasma sheath layer, in radio-frequency voltage is the half period of bearing, and the surface of ion bombardment workpiece to be machined; In radio-frequency voltage is positive half period, the surface of electron bombard workpiece to be machined.The quality of ion is heavier because electron mass is light; Electronics is more easily near the surface of workpiece to be machined, and at the surface aggregation of workpiece to be machined, realizes electric neutrality in order to suppress electron stream; The current potential of workpiece to be machined is to the drift of negative value direction, thus the formation automatic bias.Can learn that thus the automatic bias on workpiece to be machined surface receives the influence of insulating barrier and the bottom electrode surrounding structure (like ceramic washer etc.) of bottom electrode.

After deliberation; Insulating barrier is big more in the equivalent capacity of its thickness direction; The voltage drop of insulating barrier is more little; The absolute value (size of the back bias voltage of following indication all is meant the absolute value of back bias voltage) of back bias voltage on workpiece to be machined surface that is placed on the insulating barrier top is just big more, and the radio frequency sheath layer voltage drop on workpiece to be machined surface is just big more.Otherwise the radio frequency sheath layer voltage drop on workpiece to be machined surface is just more little.Therefore, the present invention regulates the automatic bias on workpiece to be machined surface through the equivalent capacity that changes insulating barrier, thereby makes the ion energy characteristic and the distribution situation on workpiece to be machined surface satisfy technological requirement.

The present invention is used for the bottom electrode of plasma apparatus; Comprise pedestal and insulating barrier, insulating barrier is arranged on the end face of pedestal, and the equivalent capacity of insulating barrier on its thickness direction has following distribution trend: promptly; Radial direction along insulating barrier; The equivalent capacity of insulating barrier differs in size, with the difference of the energy of plasma in the radial direction that is adjusted in insulating barrier, so that place the ion energy on the workpiece to be machined surface on the insulating barrier to satisfy technological requirement along the distribution of the radial direction of insulating barrier.Here the end face of the pedestal of indication is meant pedestal that one side towards workpiece to be machined.

Adjustable insulating element according to the invention comprises the fixed bed and the layer that goes up and down, and fixed bed is fixed on the end face of pedestal, and the last plane of the last plane of fixed bed and insulating barrier is at same horizontal plane.The layer that goes up and down is positioned at the below of fixed bed and is connected with elevating mechanism, go up and down layer by elevating mechanism can away from or near fixed bed, change the equivalent capacity of adjustable insulating element with this.

Among the present invention, the radial direction of insulating barrier is meant and the perpendicular direction of thickness of insulating layer direction.After the fixed insulation parts were meant that insulating element completes, its equivalent capacity was promptly definite.After adjustable insulating element was meant that insulating element completes, its equivalent capacity can be regulated.

In order more clearly to introduce technical scheme of the present invention, following examples have been omitted electrostatic attraction electrode, only keep pedestal and insulating barrier.In addition; Because being placed on the ion energy characteristic and the distribution situation on the workpiece to be machined surface of surface of insulating layer equates with the ion energy characteristic and the distribution situation of the surface of insulating layer of bottom electrode; Therefore, following examples are only described to the ion energy characteristic and the distribution situation of surface of insulating layer.

Embodiment 1

Seeing also Fig. 3, is the sectional view of the first embodiment bottom electrode.Theinsulating barrier 32 that bottom electrode comprisespedestal 31 and is fixed onpedestal 31end faces.Pedestal 31 is processed by aluminium or other electric conducting material.Insulatingbarrier 32 is an integral structure component, and particularly,insulating barrier 32 is divided intoinner region 321 and outskirt 322, and the thickness ofinner region 321 is d1, and the thickness ofoutskirt 322 is d2.Inner region 321 adopts identical dielectric material (like pottery) to process with outskirt 322, and d1＜d2.Therefore, the equivalent capacity ofinner region 321 is greater than the equivalent capacity of outskirt 322.Whenpedestal 31 was communicated with radio-frequency power supply, the automatic bias ofinner region 321 will be greater than the automatic bias ofoutskirt 322, thereby makes the radio frequency sheath layer voltage drop of the radio frequency sheath layer voltage drop ofinner region 321 greater than outskirt 322.Embodiment 1 is an automatic bias of adjustinginner region 321 and outskirt 322 through the thickness ofinner region 321 andoutskirt 322; Thereby regulate the radio frequency sheath layer voltage drop ofinner region 321 and outskirt 322, and then make the ion energy characteristic and the distribution ofinner region 321 and outskirt 322 reach technological requirement.Being understood that, according to the different processes requirement, also can be d1＞d2, and at this moment, the automatic bias ofinner region 321 will be less than the automatic bias ofoutskirt 322, thereby makes the radio frequency sheath layer voltage drop of the radio frequency sheath layer voltage drop ofinner region 321 less than outskirt 322.

A modification asembodiment 1; Theinner region 321 and the outskirt 322 ofinsulating barrier 32 also can be two independently insulating elements; When bottom electrode is installed; At first two insulating elements are fixed, then two insulating elements are fixed on thepedestal 31, perhaps directly two insulating element splicings are fixed on thepedestal 31.

Embodiment 2

Seeing also Fig. 4, is the sectional view of the second embodiment bottom electrode.Theinsulating barrier 42 that bottom electrode comprisespedestal 41 and is fixed onpedestal 41end faces.Pedestal 41 is processed by aluminium or other electric conducting material.Insulatingbarrier 42 is an integral structure component, and particularly,insulating barrier 42 is divided intoinner region 421 and outskirt 422, and the thickness ofinner region 421 is d3, and the thickness of outskirt 422 is d4.Inner region 421 adopts the dielectric material of differing dielectric constant to process with outskirt 422, and d3=d4.When the dielectric constant ofinner region 421 during greater than the dielectric constant ofoutskirt 422, the equivalent capacity ofinner region 421 is greater than the equivalent capacity ofoutskirt 422, and therefore, the automatic bias ofinner region 421 is greater than the automatic bias of outskirt 422.Whenpedestal 41 was communicated with radio-frequency power supply, the automatic bias ofinner region 421 will be less than the automatic bias ofoutskirt 422, thereby makes the radio frequency sheath layer voltage drop of the radio frequency sheath layer voltage drop ofinner region 421 less than outskirt 422.Embodiment 2 is automatic bias of adjustinginner region 421 and outskirt 422 through the dielectric constant of adjustmentinner region 421 and outskirt 422; Thereby regulate the radio frequency sheath layer voltage drop ofinner region 421 and outskirt 422, and then make the ion energy characteristic and the distribution situation ofinner region 421 and outskirt 422 reach technological requirement.Be understood that,, can make d3 < d4 or d3>d4 according to the different process requirement.

A modification asembodiment 2; Theinner region 421 and the outskirt 422 ofinsulating barrier 42 also can be two independently insulating elements; When bottom electrode is installed; At first two insulating elements are fixed, then two insulating elements are fixed on thepedestal 41, perhaps directly two insulating element splicings are fixed on thepedestal 41.

Embodiment 3

Seeing also Fig. 5, is the sectional view of the 3rd embodiment bottom electrode.Bottom electrode comprisespedestal 51, is arranged on theinsulating barrier 52 and theelevating mechanism 53 ofpedestal 51 end faces.Pedestal 51 is processed by aluminium or other electric conducting material, and the inside ofpedestal 51 is provided with the throughhole 54 that runs throughpedestal 51, and thecarriage release lever 531 ofelevating mechanism 53 can move up and down in through hole 54.Insulatingbarrier 52 is made up of fixed insulation parts and adjustable insulating element.Particularly, insulatingbarrier 52 is divided intoinner region 521 andoutskirt 522, and wherein, the thickness ofoutskirt 522 is d6, is fixed on the end face of pedestal 51.Inner region 521 is adjustable insulating element, and adjustable insulating element comprises thefixed bed 503 and thelayer 505 that goes up and down.Fixedbed 503 is fixed on theoutskirt 522, and the upper surface of its upper surface andoutskirt 522 is at same horizontal plane.Thelayer 505 that goes up and down can adopt electric conducting material or Al such as metallic aluminium₂O₃Process Deng dielectric material.Thelayer 505 that goes up and down links to each other with an end of thecarriage release lever 531 ofelevating mechanism 53, and the other end ofcarriage release lever 531 is connected with thedrive unit 532 ofelevating mechanism 53, and under the driving ofdrive unit 532,carriage release lever 531 driveslayer 505 and moves up and down.Thefixed bed 503 and the formationhollow layer 504 between thelayer 505 that goes up and down, when going up and downlayer 505 under the driving ofelevating mechanism 53, during away fromfixed bed 503, thethickness d 5 ofhollow layer 504 increases, and the equivalent capacity ofinner region 521 increases; When thelayer 505 of going up and down during nearfixed bed 503, thethickness d 5 ofhollow layer 504 reduces, and the equivalent capacity ofinner region 521 reduces.Therefore,embodiment 3 is the automatic bias that changeinner region 521 that move by thelayer 505 that goes up and down, and with the radio frequency sheath layer voltage drop of adjustinginner region 521, and then makes the ion energy characteristic and the distribution situation ofinner region 521 and outskirt 522 reach technological requirement.

Thedrive unit 532 ofelevating mechanism 53 can be cylinder or motor, and accordingly, thecarriage release lever 531 ofelevating mechanism 53 can be polished rod or screw rod.Whendrive unit 532 was motor, motor also can connect radio-frequency power supply.Cylinder or motor are delivered to polished rod or screw rod through the transmission device (not shown) with actuating force, and transmission device can adopt the transmission device that can realize transferring power between cylinder and polished rod or motor and the screw rod on any market.

Bottom electrode among theembodiment 3 can increase the flexibility of bottom electrode with respect to the bottom electrode among theembodiment 1,2.Particularly; After bottom electrode among theembodiment 1,2 is installed in plasma apparatus; The insulating barrier of bottom electrode confirms that to its surperficial automatic bias influence if technology changes, the bottom electrode that can only more renew is to adapt to the requirement of new technology; Therefore, the bottom electrode that needs a greater number is to adapt to different processes.Yet the bottom electrode among theembodiment 3 only need be regulated the position oflayer 505 and can regulate the automatic bias of surface of insulating layer, makes the ion energy characteristic and the distribution situation of surface of insulating layer reach technological requirement.Therefore, the bottom electrode among theembodiment 3 not only can reduce the quantity of bottom electrode, reduces the manufacturing cost of equipment, and can reduce the time of changing bottom electrode, improves the operational efficiency of plasma apparatus.

A modification asembodiment 3; Also can the structure of inner region, outskirt among theembodiment 3 be exchanged; That is, with the inner region employing fixed insulation parts of insulating barrier, the outskirt of insulating barrier adopts and is similar to adjustable insulating element among theembodiment 3; Regulate the radio frequency sheath layer voltage drop of outskirt byelevating mechanism 53, can reach the ion energy characteristic and the distribution situation of adjustmentinner region 521 and outskirt 522 equally.

Need to prove that the size of the energy of plasma on workpiece to be machined of the present invention surface is after technical process finishes, and obtains through the result of measuring the workpiece to be machined surface.Particularly, for etch process, the more zone of workpiece to be machined surface etching shows that energy of plasma is bigger, needs to improve this regional automatic bias to obtain bigger radio frequency sheath layer voltage drop.Otherwise, need to reduce this regional automatic bias.For deposit film, the zone that the workpiece to be machined surface film is thicker shows that energy of plasma is bigger, needs to improve this regional automatic bias to obtain bigger radio frequency sheath layer voltage drop, promptly reduces the equivalent capacity with this corresponding insulating barrier in zone.Otherwise, need to reduce this regional automatic bias.

Be understood that, according to the workpiece to be machined result, can insulating barrier be divided into more multizone, like inner region, middle district and outskirt, the area of zones of different can be done corresponding adjustment according to handling particularly.The insulating barrier of zones of different can adopt the combination of fixed insulation parts or adjustable insulating element or fixed insulation parts and adjustable insulating element respectively; Regulate the back bias voltage of corresponding region; Thereby regulate the radio frequency sheath layer voltage drop on surface, corresponding region, and then make the ion energy characteristic and the distribution situation on work piece surface reach technological requirement.In addition, when insulating barrier comprised a plurality of adjustable insulating element, the up-down layer of a plurality of adjustable insulating elements can be driven by an elevating mechanism, also can be driven by each self-corresponding elevating mechanism.

Also need to prove; Bottom electrode provided by the invention can be applied in capacitance coupling plasma equipment, inductively coupled plasma equipment, Ecr plasma equipment and the DC discharge plasma equipment, with support, fixing workpiece to be machined.

The present invention also provides a kind of plasma apparatus; Comprise processing chamber and be arranged on the bottom electrode in the said processing chamber; Said bottom electrode adopts the bottom electrode ofembodiment 1,2,3 or its modification; Be used to regulate the plasma sheath voltage drop on the workpiece to be machined surface that is placed on the said bottom electrode, make the ion energy characteristic and the distribution situation on workpiece to be machined surface reach technological requirement.This plasma equipment can be used for plasma etching or thin film deposition processes.

It is understandable that above execution mode only is the illustrative embodiments that adopts for principle of the present invention is described, yet the present invention is not limited thereto.For the one of ordinary skilled in the art, under the situation that does not break away from spirit of the present invention and essence, can make various modification and improvement, these modification also are regarded as protection scope of the present invention with improving.

Claims (11)

1. bottom electrode that is used for plasma apparatus; Comprise pedestal and insulating barrier; Said insulating barrier is arranged on the end face of said pedestal, it is characterized in that, the equivalent capacity of said insulating barrier on its thickness direction has following distribution trend: promptly; Radial direction along said insulating barrier; The equivalent capacity of said insulating barrier differs in size, and with the distribution of the above energy of plasma of radial direction of being adjusted in said insulating barrier, thereby makes the ion energy that arrives the workpiece to be machined surface that places on the insulating barrier satisfy technological requirement along the distribution of the radial direction of said insulating barrier.

2. bottom electrode according to claim 1 is characterized in that, said insulating barrier is one-body molded by the same media material, and different at the thickness in the radial direction of said insulating barrier, or one-body molded by the different dielectric material of dielectric constant.

3. bottom electrode according to claim 1 is characterized in that, said insulating barrier is to be combined by the different insulating element of a plurality of equivalent capacitys.

4. bottom electrode according to claim 3 is characterized in that, said a plurality of insulating elements are the fixed insulation parts.

5. bottom electrode according to claim 3 is characterized in that, at least one in said a plurality of insulating elements is adjustable insulating element.

6. according to claim 4 or 5 described bottom electrodes, it is characterized in that said fixed insulation parts are to be processed or processed by the different dielectric material of dielectric constant by the same media material.

7. bottom electrode according to claim 5; It is characterized in that; Said adjustable insulating element comprises the fixed bed and the layer that goes up and down, and said up-downs layer is positioned at the below of said fixed bed and is connected with elevating mechanism, said up-down layer by elevating mechanism away from or near said fixed bed.

8. bottom electrode according to claim 7; It is characterized in that; When said insulating barrier adopted a plurality of said adjustable insulating element, the up-down layer of said a plurality of adjustable insulating elements was driven or is driven by each self-corresponding elevating mechanism respectively by same said elevating mechanism.

9. bottom electrode according to claim 7 is characterized in that said fixed bed is processed by dielectric material, and the said layer that goes up and down is processed by the material that electric conducting material or dielectric material or electric conducting material and dielectric material mix.

10. plasma apparatus; Comprise processing chamber and be arranged on the bottom electrode in the said processing chamber; It is characterized in that; Said bottom electrode adopts any described bottom electrode of claim 1-9, so that place the ion energy on the workpiece to be machined surface on the insulating barrier to satisfy technological requirement along the distribution of the radial direction of said insulating barrier.

11. plasma apparatus according to claim 10 is characterized in that, said plasma apparatus is a plasma etching equipment.

Images