KR101602508B1 - Method for probing a wafer - Google Patents

Abstract

A probing method is disclosed. In the wafer probing method, first, the Nth wafer is placed on the stage. Then, a stage is set so that the set pattern is searched at a total of five first points, which are first upper and lower points and first left and right points symmetrical with respect to a first center point and a first center point of the Nth wafer, Aligns the Nth wafer through the x and y axes. Next, the Nth wafer is probed through the positions at the first points. Then, the Nth wafer is transferred from the stage to the outside. Next, the N + Mth wafer is successively placed on the Nth wafer on the stage. Next, a total of three second points, which is any one of the second upper and lower points symmetrical with respect to the second center point and the second right point on the upper surface of the (N + M) th wafer, Aligns the (N + M) -th wafer on the x-axis and the y-axis through the stage so that the setting pattern is retrieved from the wafer. Then, the (N + M) th wafer is probed through the positions at the second points.

Description

METHOD FOR PROBING A WAFER

The present invention relates to a wafer probing method, and more particularly to a method of probing the wafer to inspect the electrical characteristics of the wafer.

In general, a semiconductor device includes a process of forming an integrated circuit by repeatedly forming a specific pattern on a wafer, a process of packaging the wafer after cutting the wafer in which the integrated circuit is formed into unit chips, Is performed on each of the unit chips constituting the wafer before the wafer is cut into the unit chips.

In the step of inspecting, the defective chip is regenerated or initially removed by determining the quantity / defect state of the chips constituting the wafer, so that the assembling cost and inspection cost in the following packaging process can be reduced .

The inspection process specifically proceeds by probing each of the chips of the wafer using a prober. Here, there is a need to align the wafer in the x and y axes to probe and probe the probe in the correct position when probing each of the chips.

However, in the process of aligning the wafers, each time the wafer is changed, the upper and lower points and the left and right points are set at five points on the upper surface of the wafer, that is, the center point of the upper surface, By aligning the wafer on the x-axis and the y-axis so that the wafer is searched for.

It is an object of the present invention to provide a wafer probing method which can shorten the processing time by reducing the setting pattern for some wafers in the case of points to be searched.

In order to achieve the above-mentioned object of the present invention, a wafer probing method according to one aspect is disclosed.

In the wafer probing method, first, an Nth (N is a natural number of 1 or more) wafers is placed on a stage. Then, the first set of upper and lower points symmetrical to each other with respect to the first center point of the N-th wafer placed on the stage and the first center point, And aligns the Nth wafer on the x-axis and the y-axis through the stage. Next, the Nth wafer is probed through positions at the first points. Then, the Nth wafer is transferred from the stage to the outside.

Next, an N + M (M is a natural number of 1 or more) wafers successively following the Nth wafer is placed on the stage. Then, any one of the second upper and lower points symmetrical with respect to the second center point of the (N + M) th wafer placed on the stage and the second center point, And aligns the (N + M) -th wafer on the x-axis and the y-axis through the stage so that the setting pattern is retrieved at a total of three second points. Next, the (N + M) th wafer is probed through positions at the second points.

Here, the Nth wafer may be the first wafer when the item is replaced. Alternatively, the Nth wafer may be the first wafer when the process conditions for probing are changed.

On the other hand, when probing the (N + M) -th wafer, the positions of the remaining two third points, which are excluded from the (N + M) th search, are compared with the first points, It is possible to calculate and probe based on the positions of the first points.

In addition, the first and second upper and lower points and the first and second right and left points may each be set at a position about 0.7 to 0.9 times closer than their respective edges from the first center point or the second center point have.

According to the wafer probing method, for the Nth wafer, first, the first and second upper and lower points symmetrical with respect to the first central point of the upper surface and the first central point, And a second central point on the upper surface of the (N + M) th wafer, the second central point being symmetrical with respect to the second central point, And probing the N-th wafer and the (N + M) -th wafer while aligning the set patterns so that the set patterns are searched at a total of three second points, which are any one of the two upper and lower points and the second right and left points, The probing process can be performed in a shorter time than in the background art. Thus, the process of inspecting electrical characteristics of multiple wafers can be performed efficiently by shortening the time of the probing process.

FIG. 1 is a view showing a schematic configuration of a wafer probing apparatus according to an embodiment of the present invention.
FIG. 2 is a flow chart illustrating a process of probing a wafer through the wafer probing apparatus of FIG. 1;
FIGS. 3-5 illustrate embodiments of a method for aligning sequentially probed wafers by the flow diagram of FIG. 2. FIG.

Hereinafter, a wafer probing apparatus and method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention in order to clarify the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a part or a combination thereof is described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

FIG. 1 is a view showing a schematic configuration of a wafer probing apparatus according to an embodiment of the present invention.

Referring to FIG. 1, a wafer probing apparatus 1000 according to an embodiment of the present invention includes a stage 100, a search mechanism 200, and a probing mechanism 300.

A wafer W is placed on the stage 100. The wafer W is a silicon single crystal plate for manufacturing a semiconductor device which is one of the integrated circuit elements, and generally has a circular shape.

The wafers W are transferred one by one to the stage 100 through the first transfer unit 12 in a state in which a plurality of wafers W are stacked and stored in the cartridge 10 disposed at an adjacent position of the stage 100 . At this time, the wafer W is laid so that a circuit pattern for performing an electrical function is exposed upward.

The retrieval mechanism 200 is transferred to the upper portion of the wafer W placed on the stage 100 through the second transfer unit 210. The search mechanism 200 comprises a camera and photographs the upper surface of the wafer W.

Thus, the search mechanism 200 searches for a setting pattern formed on the upper surface of the wafer W. [ Here, the setting pattern may be a pattern arbitrarily formed for alignment, or may be a specific pattern repeatedly formed at a specific position in a circuit pattern formed on the upper surface of the wafer W. [

At this time, the stage 100 is connected to the third transfer unit 110 to be searched for the setting pattern of the wafer W at the position where the search mechanism 200 is transferred, and the wafer W is transferred to the x- and y- . The search mechanism 200 searches the setting pattern at a plurality of points on the upper surface of the wafer W and transmits the setting pattern to the search unit 200 through the third transfer unit 110 connected to the stage 100, .

The probing mechanism 300 is transferred to the upper part of the wafer W placed on the stage 100 through the fourth transferring part 310. When the search mechanism 200 is positioned above the wafer W, the probing mechanism 300 is located outside the wafer W, The set pattern of the wafer W is retrieved and then transferred to the upper portion of the wafer W. [

The probing mechanism 300 contacts the circuit pattern of the wafer W to inspect the electrical characteristics of the circuit pattern. Specifically, the probing mechanism 300 includes a probe head 320 connected to the fourth transfer unit 310, a probe card 330 replaceable with the circuit pattern of the wafer W on the probe head 320, And a prober 340 in the form of a needle that is formed on the probe card 330 to directly contact the circuit pattern to inspect the electrical characteristics of the wafer W. [

The probing mechanism 300 is connected to the search mechanism 200 and sets a position at which the prober 340 is contacted through the positions of the setting pattern searched from the search mechanism 200. The prober 340 of the probing mechanism 300 is aligned with the search mechanism 200 and the third transfer unit 110 connected to the stage 100 so that the wafer W W). ≪ / RTI >

Hereinafter, the process of probing the wafer W using the wafer probing apparatus 1000 will be described in further detail with reference to FIG.

FIG. 2 is a flow chart illustrating a process of probing a wafer through the wafer probing apparatus of FIG. 1;

2, in order to probe the wafer W, first N (N is a natural number of 1 or more) wafers W are placed on the stage 100 through the first transfer unit 12 (S100) .

Next, the search mechanism 200 is transferred to the upper part of the N-th wafer W placed on the stage 100 through the second transfer part 210, and a total of 5 pieces of the upper surface of the N-th wafer W The Nth wafer W is aligned through the third transfer unit 110 connected to the stage 100 so that the setting pattern is searched by the search mechanism 200 at the first points S200.

The five first points are set as first upper and lower points and first left and right points that are symmetrical with respect to the first center point and the first center point on the upper surface of the Nth wafer W, do. The positions of the first points thus detected are transmitted to the probing mechanism 300 so that the position at which the prober 340 is contacted can be set.

Then, the probing mechanism 300 is transferred to the upper part of the wafer W through the fourth transfer part 310 to probe the Nth wafer W through the first points, (S300). Specifically, the probing mechanism 300 can precisely contact the prober 340 with the aligned N-th wafer W based on the searched positions of the first points.

Next, the inspected Nth wafer W is transferred from the stage 100 to the outside through the fifth transfer unit 14 (400). At this time, the first transfer unit 12 connected to the cartridge 10 may transfer the Nth wafer W instead of the fifth transfer unit 14.

Then, the wafer W is transferred from the cartridge 10 to the first transfer unit 12 (12) from the N + M (M is a natural number of 1 or more) wafers W, To the stage 100 (S500).

Next, the search mechanism 200 is transferred to the upper portion of the (N + M) -th wafer W placed on the stage 100 through the second transfer portion 210, (N + M) -th wafer W is aligned through the third transfer unit 110 connected to the stage 100 so that the setting pattern is searched by the search mechanism 200 at the second three points, (S600).

Here, the total of the three second points may be any one of the second upper and lower points symmetrical with respect to the second central point on the upper surface of the (N + M) th wafer W and the second central point, Left and right points. The positions of the second points thus detected are transmitted to the probing mechanism 300 so that the position at which the prober 340 is contacted can be set.

Then, the probing mechanism 300 is transferred to the upper portion of the wafer W through the fourth transferring portion 310 to probe the (N + M) th wafer W through the second points, The characteristic is checked (S700).

At this time, the probing mechanism 300 compares the positions of the remaining three third points, which are excluded from the search, with the first points among the upper surfaces of the (N + M) th wafer W, Based on the positions of the first points.

The probing mechanism 300 may be configured to detect the prober 340 from the aligned N + Mth wafer W based on the searched second points and the positions set from the calculated positions of the third points, Can be accurately contacted and inspected.

As described above, the N-th wafer W is first subjected to the first and second upper and lower points symmetrical with respect to the first central point and the first central point on the upper surface thereof, (N + M) wafers (W) successively following the Nth wafer (W) are arranged such that the second center point of the upper surface and the second center point of the second The first and second left and right points are symmetrical with respect to a center point of the first and second left and right points, (W) and the (N + M) -th wafer (W), the probing process can be performed in a shorter time than in the background art. Thus, it is possible to efficiently perform the process of checking the electrical characteristics of the multiple wafers W by shortening the time of the probing process.

On the other hand, the first upper and lower points and the first left and right points of the Nth wafer W and the second upper and lower points and the second right and left points of the (N + M) W, it is difficult to detect the setting pattern, and when it is set too close to the first center point or the second center point, it is difficult to determine the size of the wafer W Therefore, it is not preferable.

Thus, the first and second upper and lower points and the first and second right and left points are each set at a position about 0.7 to 0.9 times closer than their edges from the first center point or the second center point desirable.

Hereinafter, the N-th wafer W illustrated in FIG. 2 will be described in more detail with reference to FIGS. 3 to 5 with respect to various embodiments.

FIGS. 3-5 illustrate embodiments of a method for aligning sequentially probed wafers by the flow diagram of FIG. 2. FIG.

Referring to FIG. 3, the N-th wafer W for searching the positions of the first five points may be defined as the first wafer W for the same item using the same lot number .

Specifically, when performing a probing process on a plurality of wafers W manufactured with a lot number, only the first wafers W are searched at the first five points in total, It is possible to search only the positions of the second three points, such as the (N + M) th wafer W, for the subsequent remaining wafers W, thereby shortening the processing time consumed therein.

In this case, as shown in FIG. 3, the order of searching for the positions of the first points may be carried out while sequentially turning the first center point from the first upper point along the counterclockwise direction. Since this search order is only one example, this order can be changed in many other ways.

Referring to FIG. 4, the N-th wafer W for searching the positions of the first five points is defined as the first wafer W among the wafers W performing the probing process under the same condition .

Specifically, even if the item is the same as in FIG. 3, only the first wafer W placed first in the stage 100 when the process conditions for performing the probing process is partially or totally changed, 5 wafers W, and for the remaining consecutive wafers W, only the positions of the second three points, such as the (N + M) th wafer W, are retrieved and consumed The process time can be shortened.

Referring to FIG. 5, when the probing process is continuously performed on the plurality of wafers W, an Nth wafer W that searches for the positions of the first five points in total is used to detect the positions of the wafers W And may be defined as the first wafer (W) for every predetermined number.

For example, if the N is 1 and the M is an arbitrary natural number K, the Nth wafer, that is, the first wafer for each certain number of times, as shown in FIGS. 3 and 4, As shown, nK + 1 (n is 0 or a natural number of 1 or more) wafers may be used.

That is, when performing a probing process on a plurality of wafers W, only a predetermined number of the wafers W placed on the stage 100 are searched at the first five points in total, and the remaining wafers W W), it is possible to shorten the processing time consumed by searching only the positions of the second three points, such as the (N + M) th wafer W, in total.

While the present invention has been described in connection with what is presently considered to be practical and exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

W: wafer 10: cartridge
12: first conveyance part 100: stage
110: Third transfer part 200: Search device
210: second transfer part 300: probing mechanism
310: fourth transfer part 320: probe head
330: Probe card 340: Prober
1000: Wafer probing device

Claims (6)

Placing an Nth (N is a natural number of 1 or more) wafers on a stage;
The set pattern is detected at a total of five first points, which are first upper and lower points and first left and right points symmetrical to each other with respect to a first central point of the Nth wafer placed on the stage and the first center point, Aligning the Nth wafer on the x and y axes through the stage;
Probing the aligned Nth wafer through locations at the first points;
Transferring the probed N-th wafer from the stage to the outside;
Placing an N + M (M is an integer of 1 or more) wafers successively following the Nth wafer on the stage;
And a third center point of the (N + M) -th wafer placed on the stage and a second center point located on the stage, Aligning the (N + M) th wafer with the x and y axes through the stage so that the setting pattern is retrieved at second points; And
And probing the aligned N + Mth wafers through locations at the second points. 2. The method of claim 1, wherein the Nth wafer is the first wafer when the item is replaced. 2. The method of claim 1, wherein the Nth wafer is the first wafer when the process conditions for the probing are changed. delete The method of claim 1, wherein probing the (N + M) th wafer further comprises comparing positions of the remaining two third points, which are excluded from the search for the (N + M) And probing based on positions of the first points based on positions of the points. The method of claim 1, wherein each of the first and second upper and lower points and the first and second right and left points are located at a position 0.7 to 0.9 times closer than their respective edges from the first center point or the second center point Wherein the wafer is probed by the probe.

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