JPS60170241A - Semiconductor wafer flatness station - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention 1 The present invention (31) relates to the field of material processing, and specifically relates to a novel 4 [semiconductor] Niwa flatness station.

[Precautions against inventions] 21'>'The manufacturing and quality control processes used in the manufacture of A-body devices and monthly products require
'No position etc.: [Ha requires accurate knowledge of ↑1. A highly productive automated assembly line system is utilized to obtain predetermined information. Typically, the wafer is roughly centered and transported to a wafer flatness station, where the wafer is roughly centered and transported to a wafer flatness station, where the wafer is roughly centered, and the flatness station records each piece of information without indicating flatness or deviation from a particular plane or plane. It is possible to do 41 for 1 Niha. Such information may include, for example:
Photographs and graphs used in the manufacture of electronic circuit elements are utilized at various stages of processing.

[Summary of the Invention] The present invention provides a method for automatically obtaining a wafer flatness profile suitable for use in automated manufacturing and quality control.
[Provide t-station. The wafer flatness station can be incorporated into a module suitable for use with various wafer characterization stations in high-throughput material processing equipment.

The wafer flatness station of the present invention is equipped with a microbe controller and typically requires approximately 7.2 seconds after receiving a wafer to obtain a flatness profile, even without the intervention of an Aberator. During normal operations, the company processes an average of about 500 wafers per hour.

The flatness station of the present invention calculates the thickness at successive points of a plurality of points selected to substantially cover a spatial region of the sample to be contoured. and means for determining second data representative of the flatness of the sample in response to the first data. In embodiments, the flatness station of the present invention provides flatness 111 of a semiconductor wafer.
Used to gain degrees. In a preferred embodiment, the wafer flatness station includes a wafer flattening station that allows the wafer to rotate about the θ axis and move along the X, Z axes in response to θ, X, 7 control signals. In order to freely support
There is a vacuum chip that can be displaced around the orthogonal X and Z axes and rotated around the θ axis.

A permissible hinge is placed near the vacuum chuck to deliver an electrical number 11 representing the wafer thickness.

A system controller having a memory coupled to the vacuum block and weight sensor controls the θ,
Rotate the chuck so that a series of points on J, selected to substantially cover the entire expanse of the wafer, are near capacitive lens υ; move it. For each such point, the system controller digitizes a corresponding electrical signal and stores data representing the thickness of each point in an associated predetermined memory unit. It works like this.

Thickness data for all of the points populates an in-memory data table containing address locations corresponding to the spatial location of each predetermined point on the wafer. The system controller operates in response to data in the data table to create a predetermined flatness profile. Preferably, the system controller has a first central control block and a second process according to the central control block. Medium heat control pro t? The processor controls the wafer movement through the Sji flatness module and instructs the second processor to edit the data table for each wafer. The second processor is a vacuum chip [! Controllably rotate and move the vines according to instructions given by a central control processor
? Read the sensor values and create a data table. Further, the edited data is sent to a central control processor to measure a predetermined flatness profile. The flatness module of the present invention can advantageously be used to obtain flatness contours on specimens and other objects other than semiconductor wafers, such as metal masks or memory disks, without departing from the scope of the present invention. .

Features of the present invention will become apparent from the following description of embodiments in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Block diagram 10 in FIG. 1 illustrates one embodiment in which the flatness station of the present invention may be utilized.

In this apparatus 10, an alignment station 14, a flatness station 16, a sample moving device 18, and a medium flame control device Pf 1 are provided.
2 are operatively coupled. For example, sample moving device 1
8 are pairs of spaced apart rubber belts through which a sample, such as a semiconductor wafer, is continuously moved through h=++-++-tion 14, flat IQ [stations 16]. For example, the automatic elevating device (
It is located on the left side of the figure and is placed on the bell 1- by the arrow ``a'' shown in the figure.

Central control [1t? The central control processor operates the sample moving device 113 to move each wafer into the alignment stage 14.
Align the sea urchins in your mind to three
, when the two ha are aligned, the center block [one side is
Let's move on to stage 111 and 16! !
Activate the separate moving device d18 [! Ru. As described below,
:V+■t+ηThe station 16 operates to ``contour a predetermined 5[t117H good contour of the wafer. C Characterization station and automatic removal station W
Move to I (on the right side of the figure, not shown) and operate the sample moving device as shown.

Although various means can be used to align 1-C with the center of gravity of A, Yoneda Patent Application No. 360.3F'.

6. It is preferable to use the alignment station disclosed in 1. In FIG. 11
The flatness station 20 is shown.
The sensor 2G is located near the vacuum tip 22 that removably holds the wafer 24 (or (l!! sample)), and the sensor 26 is
When moved close to the tray, the thickness of parts 1-24 can be measured for each part of the chair. Renri 26 is the first
It consists of a first block 28 and a second block 1 separated from the first block 30, and a measuring head 32 is formed between them. For probes 28 and 30, type 6 lenses are good. Bu [1
-130 is fixed to the support IJ 34. The main part 28 is attached to the arm 36, and the part 28 is attached to the arm 36.
4, it is fixed with a 1J sea urchin screw 38 that is relatively movable. Ab
40 are coupled to the outputs of the y' lobes 28', 30 and are arranged successively within the head 32. Exit the Abrogoi Δshi 4, which is represented by . The analog cog-to-digital converter 42 outputs data on the thickness of each fish, and outputs the cog signal conditional -7 1-40. 5, various combinations (7p IT+-'728.30 and trust p3 condition i (Konitsu 1-40), but US 111 Tokudo'1 No. 3,99
It is preferable to use the apparatus disclosed in No. 0.005 [Capacitive thickness measurement of ungrounded cords].

An X, O, Z assembly 44 is operatively coupled to the vacuum tip 22 to move the block 11 about its axis in a sum of 0 radii jJ.
Rotate! , Move the vacuum button along the X@ and / axis! do. The X, θ, 7 assembly 44 is selected to cover the entire space of the Tsuoha 24 and is 1. :tsu1-ha22
Contains a continuous sequence of ten points; f1 type detection hetsu1
;responsive to a plurality of controls 13 that controllably activate J, Utko, and Butotsuta located near 32;

7r'+t? The bus 46 is connected to the data bus 48.
is coupled to a digital converter 42.

The bus OL 46 is dynamically coupled to a conventional latching drive 50 and an X, θ, 7 assembly 44 on the data bus. Pro lx 1J716 has RAM52 which is combined with normal h method.
Ru. The central control processor 56 has r E F I E /l
The 88 bus 58 is coupled to the data bus 48 via a connecting link. Proreza 46 is a medium heat control block [IL! The medium heat control block 56 follows and commands the book 22 to be controllably rotated and moved.
6. Execute the command given as J: to the sea urchin at a predetermined point placed near the central area, and then a predetermined point placed around the medium area of the wafer. At the same time, the processor 46 reads the output of the A/I converter 42 for each point and stores it in the RAM memory O cage via the bus/I8. write to. As explained later, each day -
The address of the column 46 corresponds to a spatial ``1 cage 1'' of points in the central area of wafer 1 and areas surrounding it. The data is sent to a central control block, which overturns a predetermined flatness contour for each square by one count.

FIG. 3A [Water valve 111] (1) It is a front perspective view of the water valve 111. This station 02 has an upper plate 64 having an elongated slot 66 therein. A capacitive thickness detection head 7 is disposed within the slot 66 and is movable along the slot (in the x direction and in the 7h direction through the slot).
0 is the first capacitive blowoff 2 and the second one separated from it.
1ti-shaped pipe 74 and passes through the slot 66. The position of the probe 72 is fixed at 1i to change the position in the Z direction.
! ! r] ■ It is attached to a capable arm 74. The arm 7/I has members 76 such as a first part 4A76 fixed to the temporary 64 and a second member 78 fixed to the bar 72.
．． It covers the leaf spring 80 fixed between 7B. The shaft to the right of the thin knob 81 that can be rotated manually is the
Control L in the Z direction with the digit "L", part U76.78
It is fixed with screws through.

A first groove 82 and a second groove 84 are provided on either side of the slot 66 and are adapted to receive a rubber belt (not shown) for transporting wafers into and out of the station.

FIG. 3B shows the wafer flat I 11 degree station 8 of the present invention.
FIG. 6 is a rear perspective view of No. 6. A vacuum book II 68 is secured to the carriage 88. A Z-axis actuator 89 controls seven axes of position of the vacuum chuck 68. A carriage 88 is slidably mounted on wheels 90 of a pair of parallel guide rails 92.
A worm gear 94 is rotatably attached to a threaded housing 96 of the kill ridge 88. One end of the A-worm gear 94 is rotatably attached to a journal bearing 98 fixed to the plate 64. The shaft of the x-axis step motor 100 is coupled to the other end of the worm gear 94 via a bearing 102. Bearing 1
02 is fixed to the plate 6/1, and the x-axis step motor 100
is fixed to the flange 104. Flange 104 is fixed to plate 64. θ-axis step motor 106
Is it Ki1? It is fixed to the ridge 88. The shaft of the θ-axis step motor 106 is fixed to the shaft of the vacuum block 17 68 by a bell 1 to a wheel device (not shown) 1-, which controls the θ-axis of the vacuum block 68. . vacuum line 10
23 controls the operating state of the vacuum check ↑・check 68.

-, /'l'l t? 46 (FIG. 2) supplies data to the drive device 50 (FIG. 2) in order to control the operating state and vacuum state of the X-axis step motor 100.0 and the Z-axis step motor 89. Control signals for X, θ, 7, and vacuum are sent via bus 48 (FIG. 2). , X-axis step L-1 in response to the X control signal.
The shaft of the worm gear 94 is engaged with the threaded housing 96 to control the position of the pull pull 68 along the X axis. Similarly, the θ axis of the vacuum tilt 68 is
In response to the .theta. control signal, the .theta.-axis step motor 106 at the lower end of the belt and wheel assembly is controlled. Further, the Z-axis of the vacuum chuck 68 is controlled by a 7-axis actuator 89 in response to the 7-axis control (i'i month).
The rON, Ir0FFJ state of the vacuum applied to the vacuum line 108 is controlled by the vacuum line 108.

FIG. 4: Flowchart 1.11 showing the operation of the central control processor of the wafer flat stage 31 of the present invention.
It is 0. 112, the central control processor enters the alignment station 14 (instructions to align the incoming wafer at its center of gravity are sent to the alignment station 14).
4, and hold until the alignment is completed as shown in block 1:1 block 114. As shown at block 116, the central controller then selects the test F! The center of gravity of 1 is a shape detection head 3
2 (FIG. 2), sends a command to the sample moving device 18 (FIG. 1) to move the sample after alignment,
Wait until the movement is complete as shown in block 118.

As shown at block 120, the medium heat control block [item 1]
Send a command to the flatness station ITI to measure the central area of the sample.

FIG. 5 shows the wafer weight station of the present invention.
This is Fu[]-Chichartoko 12, who explains the operation of Hysa. Processor 46 (FIG. 2) sends 1! to the central control processor indicated by block 124. Receive instructions to measure the central area of the sample being sampled. Tsu1-ha-ki I
Team 11 Stay/Yonbroseri, give orders! ? Lie down and execute the command ``Attempt 1 to measure the central area of 1'' as shown in block 126.X, θ.

Z, vacuum control Jinyu 1! ■PROM the fixed J-ru code
111 (FIG. 2). The processor then transfers a series of points selected to cover the entire central area of the sample into a volumetric thickness sensing head, as shown at block 128.

0°7, if; J, and the creation of a vacuum! Sends a control signal to the IJ device.

In the preferred embodiment shown in FIG. For step [1 +), move the vacuum chip from the standard position in A along the X axis to "X1 point 130" between the periphery of the wafer and the center point, and hold the wafer using the vacuum. It works. Next, the stepper motor 4J operates the θ-axis step motor to continuously move a predetermined plurality of points (in the diagram, three points arranged along the first arc 132). into the sensor's M-shaped detection head. After completing the movement along fi132, the process (
Activate the X-axis step motor to move the wafer along line 134.
Move to the left as shown by . The processor then activates the theta-axis stepper motor to move a successive number of predetermined points (three points shown along arc 136) into the capacitive sensing head.

The processor scans the sample until all of the points specified in the PROM and arranged in one jig and one pattern move into the foot shape detection head, as shown by bullet 9138. A zig-zig movement is caused as described above through the central area, as shown in block 140.
For each point, the processor stores the corresponding (if in the RAM 52) of the digital converter 42 (FIG. 2).
It is stored at a predetermined address 1 in the data table shown in FIG.

The address location corresponds to the position of each center point of the wafer determined by the rotational position 119 of the zero motor and the rotational position of the X-axis motor. After the measurements are completed, the flatness processor generates a data table representing the thickness of the medium area of the sample, indicated by block 142. Send to Rihe.

Returning to the h+/1 diagram, the 1 medium heat control pulse lasts until the data representing the thickness of the medium heat 1 area of tsu is taken as shown in block 144. 1 piece 14G
It is shown in "Yo(, 2, Proseli t, flat IL)"
- Shobu ``Accept from 1st order! Store the data of the 9th time. Block 148'' 18 (Fig. 1), and move the sample until the center of the sample is at nominal position b' above the center of the vacuum tube.
! , /[Until the movement is completed, as shown by 150: i! +5. As shown in zo[-1tsuk152,
The central control processor 11 measures the central area to [Wu]! J,'s command is flat jjJI! Returning to FIG. 55, the station processor 1 sends an area surrounding the central area of the sample according to instructions received by the central control processor as shown at block 124. The wafer flatness station pro lj decodes the command and executes the command [Measure the area surrounding the central area] as indicated by block 126.

0.7 and the code that specifies the vacuum control signal.
The primary C1- taken out from Rovb4 (Fig. 2)
j'-1 sends control signals to , into the d-shaped thickness measurement head, as shown in block 128. The Ukoha Hei 11 degree station processor is
The area surrounding the sea urchin [Chuo Ward 1] is not shown in Figure 6.
I actually follow the command. Measurements of the area surrounding the central area of the sample are made by sequentially taking a plurality of predetermined data points arranged in concentric circles starting with the outermost circle and moving inward until the innermost circle is taken. Preferably, the central control block [
Flatness stage so that one auction takes 8 yen continuously.
Give the order to play the computer. The wafer flat II state controller is activated by vacuum to lift the wafer at the center point 154 until the outermost edge 156 is located within the capacitive thickness sensing head. Move OJ! Operate the X-axis step motor to cover 13
Next, tI9 operates the θ-axis step motor to successively move a predetermined plurality of points (three points located within the outermost end 156 in the diagram) closer to the capacitive sensing head.

In the flatness station controller, the θ-axis step motor is rotated to advance the measurement over the entire circle as shown by block 138.

As shown by block 1/IO, for each point, the program converts the reading of the inverter 112 (Fig. 2) to the data table of RAM 52- (Fig. 2). Store at a predetermined address location.

The j'dress 1 gougeon is a circle 156-1 determined by the rotational position of the θ-axis and the rotational position of the X-axis motor.
correspond to the position of each point in . After the points within the outermost edge are collected in the metric, as shown in block 142,
degree control pro t? (J returns the data to the medium heat control brozeza.

Returning to FIG. 4, the central control processor waits until the data within the outermost edge has been collected, as shown at block 158, and then selects a point along the outermost edge, as shown at block 160. It represents the thickness and stores the aforementioned data.

When the data within the innermost edge has not been collected, as shown in block 162, the central control block sends commands to the 10° station processor to continue rotating the wafer, as shown in block 164. Zuyoni next inner inner position n 1
57 (Figure 6). The flatness control process receives instructions for the inner circle of the method (J,
1? is repeated. In block 166, the sea urchin,
Once the data within the innermost edge has been collected, the central control processor sends a command to the flatness control processor to stop the rotation of the sample and start the vacuum. The pick is moved to the nominal position and the sample is dropped and held until the move is complete as indicated by block 168. The central control process υ then calculates a predetermined flatness profile from the thickness data, as shown at block 170.

Central control program? υ repeats the above process for each wafer passing through the flatness station.

It will be seen that various 1/2 degree contours can be subtracted from the data. For example, a flat 1σ translocation can be fit tI from a plane defined by three predetermined points, from a plane defined by the least mean-square C appropriate to the data, and from a plane defined by the ideal back surface of the wafer. Predetermined date
An example of an algorithm for the adjustment of data for simple is given below in Pascal cost.

pnoc+-Hikime ([8 DJIIST (formerly IHBEI?
OF-POINTS.

INTEGER; XPO3ITION, YPO3ITION, TII
ICKHFSS: ARRAYr 1. , N1111
BIRQ3 POTNTSIOF RE^1: To V II
NrWX, Nil', FIATHESS: ARR
AY (1,, N11HB [1j-OF POIN'r
S] OF RE^1-:HATI+IX[1,,3,
1,,3 OF IIEAl; orrso-X
, (IFF'SEI'-j', 0FFSFI'-
2: RF Δ1);
01NTS DOEGIN NE14X [I] : = XPO3[11ON'
[rl”H to TRrX[1,1] + Y PO3IT
ION [I] ”HATltlX[1,2] +T
l1ICKN[SS[I]*HA■1(I×shi1.3]
, (S[1X; N[WY [I 1 : =XPO3ITION [+
1 ” TRIX[2,1] +YPO3ITI to M
ON [l 1 ”HATllIX[2,2]-1-T
IIICK old-3SII]” HATllIX 2,
31 + 0FFS [: r V ; Fl-ATNESS
[r]: = Xl'0SITrON r r
1 “HATR4X[3,1] +YPO3ITION
[1] * TO H TRIX[3,2] -1-TIIICKNESS [I] ” HATR
TX [3,3]+0FFSET-l; END; FOIt 100P END; PROCEDIIRE Here, NLJM13EROF POINTS is
Great versatility, XPO3IT ION, YPO3r T
I ONL, LIa/jylJ4mi=, (X, Y),
G, is the axis of each data, T l-110K N F S
S is flatness stage S color (1) storage data, MAT
RIX, 0FFSF'l-,,X, OFF"SET'
-Y, 0FFSF3 4-7 (, 1t10 is a new plane reference.

The flatness module of the present invention is '4' for objects other than T.
7111i and that many modifications are possible without departing from the scope of the invention.5 The foregoing examples are not intended to limit the scope of the invention.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of an apparatus in which the T-flat melon station of the present invention can be used. FIG. 2 is a block diagram showing one of the flatness stations of the present invention.
FIG. 313 is a rear perspective view of the same stage. FIG. 4 shows the flatness station of the present invention. FIG. 5 shows the operation of the second part of the 111 degree wafer flatness stage of the present invention. Char 1-. FIG. 6 is a conceptual diagram showing the operation of the flatness station of the present invention. 12.46...Bu [1t? 14... Alignment station 16, . 20, 62.86... Flat bean station 18... Sample moving device 22, (58... Vacuum holder 24... Uko I A 26-t?nri 28... 1st step [] -Abu 3o...2nd Bu "1-bu 32.70
...Detection head 36.74...Arm 40...
AB [1 signal strip A1 included] Knit 42...Analog-
Digital converter 56...Central control block 1-9
o...Middle wheel 89.100,106...Step motor IG 3A

Claims (1)

[Scope of Claims] (1) A device for forming a flat contour on a sample, the device forming a flat outline on a sample, which substantially covers a predetermined spatial region of the sample, and forming a contour on a plurality of consecutive points selected from a plurality of points substantially covering a predetermined spatial region of the sample means for obtaining first data representing a thickness at a point; in response to the first data;
(2) The means for obtaining the first data is a thickness detection head;
means for moving the sample to position the sequential points of the predetermined points within the thickness detection head;
(3) The device according to claim 1 (3) wherein the detection head is arranged in the same direction as the first and 20th eight hanging-shaped sections; The equipment described in the section! . (4) The device according to claim 2m, wherein the front &1 moving means has a vacuum filter. (5) The vacuum chuck is rotatable by θ radians about its axis in response to θ, XS7 control signals, and movable along the orthogonal X1z axis, and the thickness detection head θ,× to actuate and control the vacuum chuck to be placed near the knock and further move the succession of the predetermined points near the thickness sensing head.
17 The means for issuing the control signal is provided in claim 4.
Equipment described in Section. 6. The apparatus of claim 1, wherein the means for obtaining the second data comprises a processor operative in response to the first data to estimate a flatness profile. (7) θ around the axis in response to θ, X, and Z control signals.
means for detachably holding the sample so as to rotate in radians and move along the orthogonal X1z axes; a hinge for holding the thickness measuring head; and a hinge coupled to the thickness measuring head and the holding means; , selected to cover substantially the entire spatial area of the sample]-c holding means for sequentially transferring a plurality of points i1 into the measuring head, respectively;
1 possible rotation and movement of θ, 41'! means for storing data representing the n-ness of each point in the memory of the data solver; Test 1 (1 Hei j, Q I
Q station. (8) The holding means is a vacuum stick fixed to the carriage;
- an X-axis actuator operatively coupled to the shaft; a Z-axis actuator fixed to the shaft for moving the vacuum pull along the shaft; The apparatus according to claim 7, which rotates the θ-axis step motor fixed to the 1-V ridge to the right in order to rotate by one angle. (Claim 71 in which the Lamp 1 is a capacitive sensor) (11) A device according to claim 9, comprising means coupled to one of said probes for moving said probe toward and away from the other probe. 11) The device according to claim 10. (12) The device according to claim 7, wherein the means for holding the memory has a proref 1. (13) The device for holding the memory. The apparatus according to claim 71Qj, which sends the sample to the sample and moves the sample to the next level without taking it out from the beginning. Measure and try the address location corresponding to each of the 10 spatial locations 1r, store the thickness measurements of each of the points in memory, and write the addresses for all of these points. Buch's method for determining a predetermined flat contour of the trial, which consists of the step of determining the flat structure of the trial from information stored in a "1-couple" section. (15) The measurement step Support another at a point far from its center, successively measure the thickness of several selected points in or near the center area of the trial, and support +:, t C trial near the center of the king. 14. The apparatus according to claim 14, comprising: continuously measuring the thickness of the sample at a plurality of points selected to surround the central area of the sample; (16) the center of the sample; 16. The apparatus of claim 15, wherein the step of measuring an area is performed by moving the central area of the sample in a predetermined pattern under a thickness sensing head. 1j. Apparatus according to claim 16, comprising: (18) a step of measuring around the central area, in which the step of measuring around the central area moves the specimen in a predetermined pattern surrounding the central area of the sample under the thickness sensing head; An apparatus according to claim 15, wherein the predetermined pattern includes concentric circles. Apparatus according to claim 14, wherein the thickness measurements of each of said points are stored in a table, the address locations corresponding to the respective spatial locations of a plurality of predetermined points on the specimen. In response to the 5°(21)θ, A means for holding the Ic; a capacitor 4) for holding the capacitor 4-shaped thickness measuring head;
controllably rotating the holding means to sequentially transfer into each capacitive measuring head a plurality of points on the wafer selected to substantially cover the overall spatial scorching of the wafer; A data table that outputs a control signal of θ,×,7 to move the memories connected in such a way as to read 1 column at a predetermined address corresponding to the position of each of the points in the data table. means for storing data at each point in the memory; means responsive to the data in the data table for estimating a predetermined contour of the wafer; Wafer flatness station consisting of: