KR101133633B1 - Power supply apparatus and driving method thereof - Google Patents

Abstract

PURPOSE: A power supply unit and a drive method thereof are provided to prevent process errors due to high voltage using low output voltage. CONSTITUTION: A transformer(200) insulates and transforms primary input voltage. A switching unit(210) comprises a first switching unit(210_1) and a tab switching unit(210_2). The first switching unit and the tab switching unit comprise a tab switch such as a bidirectional SCR(Silicon Controlled Rectifier). The isolating transformer outputs voltage of maximum 1900 V during driving of a CVD power supply unit in order to satisfy the rated voltage specification of the tab switch of the first switching unit. A transformer(220) outputs secondary voltage corresponding to 1020V, 630V, 390V, and 240V through an output tap.

Description

Power Supply Apparatus and Driving Method Thereof

An embodiment of the present invention relates to a power supply device and a driving method thereof, and more particularly, a high voltage is applied during the initial driving of a device in a power supply device used for a chemical vapor deposition (CVD) device or the like. The present invention relates to a power supply device and a driving method thereof in which a voltage can be applied in consideration of a rating of a switch when applied.

The contents described in the following sections provide background information related to the embodiments of the present invention, but it does not constitute a prior art.

The power supply is used in most of the equipment driven by the electricity, it is generally used to convert variously according to the characteristics of the equipment. For example, various equipments can convert 110-220 V commercial power through an internal power supply. For example, CVD devices used in semiconductor manufacturing can use high voltages of hundreds to thousands of V.

In the CVD process, a process is performed for about 72 hours. When the first tungsten wire is put into a reactor and a current is maintained at 1000 to 1200 ° C., silicon molecules in chlorosilane or trichlorosilane gas adhere to the tungsten surface and grow. Therefore, the round rod-shaped silicon becomes thicker with time, resulting in a polycrystalline silicon ingot. Due to this characteristic, the CVD power supply requires a high voltage and a small current at the beginning of driving, and a large current of a low voltage is required over time.

1 is a circuit diagram of a conventional CVD power supply. For reference, in FIG. 1, only one phase of a three-phase transformer having the same phase is shown for convenience of description.

As shown in FIG. 1, a conventional CVD power supply includes an isolation transformer 100, a tap change switching unit 110, and a load 120.

Here, the isolation transformer 100 insulates the input power and outputs it in multiple stages. For this purpose, the secondary coils of the isolation converter 100 are divided from each other.

In addition, the tap-changing switching unit 110 controls the multi-stage output of the isolation transformer 100 by using the first to fifth switches SW ₁ to SW ₅ and transmits them to the load 120.

2 is a view showing the operating characteristics of the apparatus of FIG.

As shown in FIG. 2, the CVD power supply of FIG. 1 initially outputs a small current of high voltage through the load 120 and outputs a large current of low voltage over time. In order to satisfy this characteristic, the CVD power supply of FIG. 1 initially turns on the first switch SW ₁ so that the voltage corresponding to step 1 of FIG. 2 is output to the load 120, and then the first switch is switched on. (SW ₁ ) is turned off and the second switch (SW ₂ ) is turned on to output the voltage corresponding to step 2 of FIG. 2 to the load 120. In this manner, the third to fifth switches ( SW ₂ to SW ₅ ) are sequentially turned on to output a voltage corresponding to step 5 in step 3 of FIG. 2.

However, in the conventional CVD power supply, since the voltage required by the load 120 initially corresponds to 3500 V, the CVD power supply may be designed within the rated limit of an element such as a bidirectional SCR constituting the tap-changing switching unit 110. There are many difficulties. In other words, in FIG. 1, the tap-changing switching unit 110 is configured as a bidirectional SCR, and the rated voltage of each switch is generally selected to be about 2.5 times the use voltage, and for the first switch SW ₁ , about 7000 V or more. It is not easy to configure a bidirectional SCR switch with a high rated voltage.

For example, even if a high output voltage can be obtained through a load, problems such as a decrease in the withstand voltage of a bidirectional SCR providing a high voltage may occur. May occur.

An embodiment of the present invention is to provide a power supply device and a driving method thereof that can provide a voltage in a range that satisfies the rated voltage specifications of the switch during the initial driving of the power supply device.

According to an embodiment of the present invention, a power supply apparatus includes: a transformer having first to nth output taps and converting input power to output multiple stage voltages having different levels at the output taps; A plurality of switching elements, one side of which is connected to one node of one end of the output tap and the first to nth output tabs connected to each other, and the other side of which is connected to one side of a load, and outputs the voltage of the multi-stage A tap-changing switching unit having a; A first switching unit connected to an intermediate point of the load that divides one end of the output tap and the voltage at both ends thereof and outputs a voltage of the highest level among the voltages of the multi-stage; Electrically connected to both ends of the n-th output tap for outputting a voltage of the lowest level and to one side of the load, and driven during operation of the first switching unit to regulate a current classified between both ends of the load at the intermediate point; It characterized in that it comprises a load current control unit.

In addition, the driving method of the power supply apparatus according to an embodiment of the present invention switching in the transformer having a plurality of output taps electrically connected to one end of the output tap for outputting the highest level of voltage and the intermediate potential point of the load to distribute the voltage Driving a part to output the highest level voltage; And a load current controller electrically connected between one side of the load classified at both ends at the intermediate potential point and the ground when the current classified at both ends at the intermediate potential point of the load is not uniform, thereby driving both ends of the load. It characterized in that it comprises the step of adjusting the current flowing to.

According to the embodiment of the present invention, the switch withstand voltage generated by the use of a high voltage as in the prior art, for example, because a low level voltage that satisfies the rated voltage specification of the switch is used during the initial driving of a power supply used in a CVD apparatus or the like. The reduction problem can be improved.

In addition, the use of a relatively low output voltage can prevent problems such as process defects caused by high voltage in advance.

Furthermore, it is possible to prevent the heat generation problem that may occur due to the nonuniformity of the electrical characteristics due to the manufacture of the resistance element constituting the load, and the unbalance problem of the current caused by the resistance drop due to the heat generation.

1 is a circuit diagram of a typical CVD power supply,
FIG. 2 shows the operating characteristics of the device of FIG. 1;
3 is a circuit diagram of a power supply apparatus according to an embodiment of the present invention;
4A is a state diagram of a state in which the first switching unit and the load current adjusting unit of FIG. 3 are driven;
4B is an equivalent circuit of FIG. 4A,
FIG. 5A is a simplified diagram of the circuit of FIG. 4B for description of current balance between two load stages; FIG.
5B is a diagram showing an output waveform of FIG. 5A;
6A is a view illustrating a driving state for a positive voltage section in FIG. 5A;
6B is a view illustrating a driving state for a negative voltage section in FIG. 5A;
6C is a diagram illustrating output waveforms of FIGS. 6A and 6B.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

3 is a circuit diagram illustrating a power supply device according to an exemplary embodiment of the present invention.

As shown in FIG. 3, the power supply apparatus according to the embodiment of the present invention is a power supply apparatus that can be used, for example, in a CVD apparatus, and includes a transformer 200, a first switching unit 210_1, and a load current controller 220. It may further include a tap switching switching unit 210_2, a load 230 and a switching controller (not shown). Here, the load current controller 220 may include an auxiliary tap 6 and a second switch 220a.

The transformer 200 is an insulation transformer and may insulate and transform the primary input voltage to output in multiple stages from the secondary side. To this end, the isolation transformer 200 includes a plurality of output taps or connection points in the secondary winding, such as a first switching unit 210_1 including a tap change switch, a tap change switching unit 210_2, and a load current controller 220. Output voltages of different levels according to control. According to the exemplary embodiment of the present invention, the isolation transformer 200 may satisfy the rated voltage specification of the tap-changing switch of the first switching unit 210_1 by outputting a voltage of, for example, a maximum of 1900 V when the CVD power supply is driven. In addition, the transformer 220 may output secondary voltages corresponding to 1020 V, 630 V, 390 V, and 240 V through the respective output taps tap 1 to tap 5. If voltage margin is not taken into consideration, voltages corresponding to 1750 V, 900 V, 450 V, and 275 V may be output.

The switching unit 210 is divided into a first switching unit 210_1 and a tap switching switching unit 210_2, and the first switching unit 210_1 and the tap switching switching unit 210_2 may be, for example, bidirectional SCR (Silicon Controlled Rectifier). It includes the same tap-change switch. Here, the first switching unit 210_1 is twice the voltage at the load 230 using a voltage of 1750 V considering the margin output through the first output tap 1 of the secondary side of the transformer 200. That is, it is driven when trying to obtain a voltage of 3500 V. On the other hand, the tap change switching unit 210_2 is driven to sequentially obtain voltages of 1750 V, 900 V, and 450 V output through the first to fourth output taps tap 1 to tap 4.

Here, the first switching unit 210_1 may include a first switching device SW ₁ , a second switching device SW ₂ , and a ninth switching device SW ₉ as an auxiliary switch. One side of the first switching element SW ₁ is connected to one side of the first output tap 1 of the transformer 200, for example, the upper side as shown in the drawing, and the other side is connected to each other in series with a resistor R ₁ to R ₄ . by way of the ninth switching element (SW ₉₎ to the intermediate node (Nc) of the load (230), electrically connecting comprising a. Here, the common connection point Nc of the load 230 corresponds to a point for distributing the voltage across both ends of the load 230, and the other side of the load 230 is grounded. In addition, one side of the second switching element SW ₂ is connected to a node, that is, the first connection point N1, to which the first output tap 1 and the second output tap 2 are connected to each other, and the other side of the second switching element SW ₂ . The device SW ₉ may be electrically connected to the common connection point Nc of the load 230. One side of the ninth switching element SW _{9, which} is an auxiliary switch, is connected to one side of the first and second switching elements SW ₁ and SW ₂ , and the other side thereof is connected to the common connection point Nc of the load 230.

The tap-changing switching unit 210_2 receives the voltage of the transformer 200 and, as illustrated in FIG. 2, the third to sixth switching for outputting a voltage corresponding to the second to fourth steps (steps 2 to 4). Device (SW ₃ ~ SW ₆ ). One side of the third switching device SW ₃ is connected to one side of the first output tap 1 of the transformer 200, and the other side thereof is connected to one side of the load 230. In addition, one side of the fourth switching device SW ₄ is connected to the first connection point N1 in which the first output tap 1 and the second output tap 2 are connected to each other, and the other side is one side of the load 230. Connect to One side of the fifth to sixth switching elements SW ₅ to SW ₆ may include a second connection point N2 and a third output tap having the second output tap 2 and the third output tap 3, respectively. Tap 3 and the fourth output tap 4 are connected to the third connection point N3 connected to each other, and the other side is commonly connected to one side of the load 230.

The load current controller 220 includes a sixth output tap 6 and a second switching unit 220a as an auxiliary tap of the fifth output tap 5 of the secondary side of the transformer 200, and includes a second switching unit. The unit 220a includes seventh and eighth switching elements SW ₇ and SW ₈ . Here, one side of the sixth output tap tap 6 is connected to the other side of the fifth output tap tap 5 and is grounded. One side of the seventh switching device SW ₈ is connected to the fourth connection point N4, in which the fourth output tap 4 and the fifth output tap 5 are connected to each other, and the eighth switching device SW _{8 is} connected. One side is connected to the other side of the sixth output tap tap 6, and the other side of the seventh and eighth switching elements SW ₇ and SW ₈ is commonly connected to one side of the load 230.

The seventh and eighth switching elements SW ₇ and SW ₈ constituting the load current controller 220 have a resistance R ₁ based on the common connection point Nc of the load 230 when the first switching unit 210_1 is driven. And the current at both ends of the first load end consisting of R ₂ and the second load end consisting of the resistors R ₃ and R ₄ are controlled to be uniform. In other words, since the resistors R ₁ to R ₄ constituting the load 230 in a power supply such as an actual CVD apparatus cannot have the same resistance value due to manufacturing characteristics, the current flowing through the resistance of the load 230 is not the same. The amount of heat generated by the flowing side is increased. If the temperature is high due to the characteristics of the load 230, the resistance value is lowered to continue the vicious cycle in which more current flows. As such, when the current at both ends of the load 230 is uneven, the load current controller 220 uniformly adjusts the uneven current.

In addition, the seventh switching element SW ₇ of the load current controller 220 may operate to uniformly adjust currents at both ends of the first and second load stages, and may also perform a tap-change switching unit 210_2 as a kind of auxiliary function. 2 may operate to output a voltage corresponding to the fifth step (step 5). In other words, in order to output the voltage of the fifth step (step 5), the eighth switching device SW ₈ is turned off and only the seventh switching device SW ₇ is turned on to load a voltage of 275 V. Output to 230. If margin is taken into account, a voltage of about 240 V will be output.

4A is a diagram illustrating a driving state of the first switching unit and the load current controller of FIG. 3, and FIG. 4B is an equivalent circuit of FIG. 4A.

4A and 4B together with FIG. 3, the power supply device according to the embodiment of the present invention turns only the first switching device SW ₁ of the first switching unit 210_1 during, for example, the initial driving of the CVD power supply. Although it is preferable to turn on, the second switching device SW ₂ may be turned on at the same time in consideration of problems such as power factor. In addition, when an imbalance of current occurs at both ends of the load 230, the seventh switching element SW ₇ and the eighth switching element SW ₈ constituting the load current controller 220 may be driven together.

Since a voltage of 240 V is generated at both ends of the load current controller 220, between one side of the resistors R ₁ and R ₂ of the load 230 connected in series with each other, that is, the intermediate potential point of the load 230, that is, the common connection point Nc, and the ground. A voltage of up to 2140 V can be obtained, whereas a maximum of 1900 V can be obtained between one side of the resistors R ₃ and R ₄ , which are the intermediate potential points Nc, and ground, and considering the margin, a voltage of 1750 V can be obtained. Accordingly, a voltage of 3500 V at both ends of the load 230 in consideration of a margin between the potential point V1 and the ground to which the other side of the seventh switching element SW ₇ and the eighth switching element SW ₈ are commonly connected. You will get.

As shown in FIG. 4B, since the total current flowing into the load 230 Iout = I_12 + I_34, I_12 and I_34 may be expressed as Equation 1 and Equation 2 by summarizing I_12 and I_34 again with respect to the load resistance and voltage. .

In Equations 1 and 2, since the total load current Iout and the voltage Vout are determined by the first and second switching devices SW ₁ and SW ₂ , the seventh switching device SW ₇ ) and the eighth switching device SW ₈ to control the electric potential of V1 to control the current flowing through each resistance stage.

FIG. 5A is a simplified diagram of the circuit of FIG. 4B for describing a current balance between two load stages, and FIG. 5B is a diagram illustrating an output waveform of FIG. 5A.

When Figures 5a and reference with Figure 5b 3, between the resistors R ₁ and R ₂ portion bottom ground on one side and a load current control unit 220 constituted by a voltage of 2140 V is output, the resistance to the R ₁ and R ₂ It can be seen that between the other side of the load stage and the ground of the load current controller 220, the V1 voltage, that is, the voltage of 240 V, is output in different phases. In other words, if the seventh switching element SW ₇ outputs a voltage in phase with the Nc voltage, the eighth switching element SW ₈ outputs a voltage inverse to the Nc voltage.

FIG. 6A is a diagram illustrating a driving state for a positive voltage section in FIG. 5A, FIG. 6B is a diagram showing a driving state for a negative voltage section in FIG. 5A, and FIG. 6C is a diagram illustrating the output waveforms of FIGS. 6A and 6B. Indicates.

As shown in FIGS. 6A and 6C, in the positive voltage section of the output voltage, the switching element SW ₇ _ _A positioned at one side of the seventh switching element SW ₇ , that is, the upper part of the drawing, is placed in the diode mode. At this time, the voltage V ₁ is a positive voltage, which reduces the voltage at both ends of the first load terminal consisting of the resistors R ₁ and R _2. One side of the eighth switching element SW ₈ , which is similarly positioned on the upper side of the drawing, is operated. switching elements (SW ₈ _ _a) a seventh switching element ((switching element one side of SW ₇₎ (SW ₇ _ _a) is turned conductive thereby at some point in the interval to be turned on, one switching device (SW ₇ _ _a As the current of C) is commutated, the voltage at both ends of the first load terminal consisting of the resistors R ₁ and R ₂ becomes large, in this manner, it is possible to balance the current flowing at both ends of the load.

On the other hand, as shown in FIGS. 6B and 6C, in the negative voltage section of the output voltage, the switching device SW ₇ _ _A located at the other side of the seventh switching device SW ₇ , that is, at the bottom of the drawing, is in diode mode. and operating in, an eighth switching element (SW ₈₎ of the other switching element (SW ₈ _ _B) a seventh switching element ((switching element one side of SW ₇₎ (SW ₇ _ _a) a turn-on event of the period in which The current flowing through both ends of the load is controlled by adjusting the voltage across both ends of the first load end including the resistors R ₁ and R ₂ in a manner that conducts at the time point.

Until now, in the exemplary embodiment of the present invention, the seventh switching device SW ₇ of the load current controller 220 operates when outputting the voltage corresponding to the fifth step, referring to FIG. It is described to operate even when trying to adjust uniformly. However, in still another embodiment of the present invention, although not shown in a separate drawing, a current of both ends of the load 230 is further increased by additionally configuring a second seventh switching element connected in parallel with the seventh switching element SW ₇ . It may be possible to operate the seventh switching device (SW ₇ ) to adjust, and to operate the second seventh switching device to output the voltage of the fifth step.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

In addition, the terms "comprise", "comprise" or "having" described in the specification mean that a corresponding component may be included unless otherwise stated, and thus, other components are excluded. It should be construed that it may further include other components. All terms, including technical and scientific terms, have the same meanings as commonly understood by one of ordinary skill in the art unless otherwise defined. Terms used generally, such as terms defined in a dictionary, should be interpreted to coincide with the contextual meaning of the related art, and shall not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present invention.

An embodiment of the present invention is applicable to a power supply device and a method of driving the same. According to an embodiment of the present invention, a low level voltage satisfying a rated voltage specification of a switch during initial driving of, for example, a power supply device used in a CVD device or the like is provided. As a result, it is possible to solve the problem of reducing the switch breakdown voltage caused by the use of a high voltage as in the prior art, and also to prevent problems such as process defects caused by the high voltage by using a relatively low output voltage. In addition, it is possible to prevent the heat generation problem that may occur due to the nonuniformity of the electrical characteristics according to the manufacture of the resistance element constituting the load, and the unbalance problem of the current generated by the resistance drop due to the heat generation.

100: isolation transformer 110, 210_2: tap-changing switching unit
120: 230: Load 200: Transformer
210_1: first switching unit 220: load current control unit
220a: second switching unit

Claims (12)

A transformer having a first to nth output taps and converting input power to output a multi-stage voltage having different levels at the output taps;
A plurality of switching elements, one side of which is connected to one node of one end of the output tap and the first to nth output tabs connected to each other, and the other side of which is connected to one side of a load, and outputs the voltage of the multi-stage A tap-changing switching unit having a;
A first switching unit connected to an intermediate point of the load that divides one end of the output tap and the voltage at both ends thereof and outputs a voltage of the highest level among the voltages of the multi-stage; And
Electrically connected to both ends of the n-th output tap for outputting a voltage of the lowest level and to one side of the load, and driven during operation of the first switching unit to regulate a current classified between both ends of the load at the intermediate point; Load current control unit
Power supply comprising a. The method of claim 1,
The power supply further includes a switching control unit,
And the switching control unit controls the tap change switching unit, the first switching unit, and the load current control unit. The method of claim 1, wherein the first switching unit,
First and second switching elements each connected to both ends of the first output tap for outputting a voltage of a highest level; And
One side is connected to the other side of the first and second switching elements, the other side is an auxiliary switching element connected to the intermediate point
Power supply comprising a. The method of claim 1,
And the other side of the n-th output tap and the other side of the load are grounded. The method of claim 1,
The tap switch switching unit includes a third to sixth switching element as the plurality of switching elements. The method of claim 5, wherein the load current control unit,
An auxiliary tab having one side connected to the other side of the nth output tap and having the same electrical characteristics as the nth output tap; And
One side is connected to one side of the n-th output tap and the other side of the auxiliary tap, respectively, the other side is connected to each other second switching unit for connecting to one side of the load
Power supply comprising a. The method of claim 6, wherein the second switching unit,
A seventh switching element connected at one side to one side of the nth output tap and at another side to one side of the load; And
One side is connected to the other side of the auxiliary tap, the other side of the eighth switching element connected to one side of the load
Power supply comprising a. The method of claim 7, wherein
The first to eighth switching device is a bidirectional SCR (Silicon-Controlled Rectifier). Outputting a voltage of the highest level by driving a switching unit electrically connected to one end of an output tap for outputting a voltage of the highest level in a transformer having a plurality of output taps and an intermediate potential point of a load that distributes voltage; And
When the current classified at both ends at the intermediate potential point of the load is not uniform, the load current controller electrically connected between one side of the load classified at both ends at the intermediate potential point and the ground is driven to both ends of the load. To adjust the current flowing
A method of driving a power supply comprising a. 10. The method of claim 9,
The load current controller includes a bidirectional SCR of a first group and a bidirectional SCR of a second group,
The bidirectional SCR of the first group outputs a voltage of an in-phase smaller than the voltage of the highest level,
The bidirectional SCR of the second group outputs a voltage which is in phase with the in-phase voltage. The method of claim 10, wherein the load current control unit,
Temporarily turning on one side SCR of the second group of bidirectional SCRs in a section in which one side SCR of the first group of bidirectional SCRs is turned on;
In the section in which the other side SCR of the first group of bidirectional SCR is turned on, the other side SCR of the second group of bidirectional SCR is temporarily turned on,
The driving method of the power supply, characterized in that for adjusting the current. The method of claim 11,
One side SCR of the bidirectional SCRs of the first group and one side SCR of the bidirectional SCRs of the second group are connected in the same direction,
The other side SCR of the bidirectional SCRs of the first group and the other side SCR of the bidirectional SCRs of the second group are connected in the same direction.

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