JPH10303111A - Aligner and manufacture of device thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the throughput decline of an aligner caused by the increase of the carrying-in and carrying-out frequencies of a test reticle. SOLUTION: An aligner is provided with an original plate stage which holds an original plate having an exposing pattern at an exposing position and a carrying means which carries in and out the original plate. The carrying means is provided with a rotatable original plate carrying-in/out arm 8 having original plate holding sections 8b and 8c which can hold the original plate at two symmetrical locations with respect to the center of rotation on the carrying route of the original plate and a rotationally driving means which rotationally drives the arm 8. Therefore, the carrying means can simultaneously carry in and out original plates to and from the original plate stage. The arm 8 is also provided with an expanded holding section 8d which can hold the original plate at one or more locations where the section 8d does not interfere with the holding section 8b and 8c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an LSI, a VLSI
The present invention relates to a semiconductor exposure apparatus and a device manufacturing method for manufacturing a semiconductor device such as a semiconductor device.

[0002]

2. Description of the Related Art FIG. 4 is a perspective view schematically showing a reticle transport path in a conventional semiconductor exposure apparatus. In this apparatus, the reticle cassette robot 2 is actually surrounded on all sides by the reticle cassette libraries 1A and 1B, the relay storage unit 3 and the elevator unit 1C, and is mounted so as to be able to move up and down by the elevator unit 1C. For this reason, FIG.

[0003] Reticle cassette library 1A or 1
The reticle stored in the reticle cassette in an arbitrary slot of B is not used in the relay storage unit 3 together with the reticle cassette by the raising / lowering of the reticle cassette robot 2 and the expansion / contraction operation of the arm (the cassette is stored). (Not) moved to a slot. Subsequently, the reticle cassette is opened in the relay storage unit 3, and only the reticle stored therein is taken out of the reticle cassette by the elevation of the relay storage unit 3 and the expansion and contraction of the arm of the reticle robot 4.
Next, the retil is moved to one side (lifter side) of the two reticle holding sections of the lifting / lowering / rotating arm 6 by the extension / retraction of the arm of the reticle robot 4 and the lifting / lowering and positioning mechanism of the lifter 5. Further, the reticle of the reticle holding portion on the lifter side of the rotating / elevating arm 6 is moved to the reticle cassette library 1A or 1B by an operation completely opposite to the above-described transport procedure.

FIGS. 5 and 6 are a top view schematically showing a positional relationship among a lifter, a lifting / lowering / rotating arm, and a reticle stage, and a cross-sectional view taken along a line AB. The elevating / rotating arm 6 has a mechanism for directly carrying in and out the reticle with respect to the reticle stage. In all the steps using the reticle, the reticle is moved in the order of raising, rotating and lowering the lifting / rotating arm 6 via the reticle holding portion currently located on the lifter 5 side of the lifting / rotating arm 6. The reticle is carried into the reticle stage 7, and after the reticle is used, the reticle is carried out from the reticle stage 7 to the reticle holding portion of the lifter 5 side of the lifting / rotating arm 6 by exactly the same operation as the reticle, and finally the reticle cassette library 1A or Collected in 1B.

When a reticle that has been used is already mounted on the reticle stage 7 and a reticle to be used next is held in the reticle holding portion of the lifter / rotation arm 6 on the lifter 5 side, the reticle is moved up and down. By causing the rotating arm 6 to carry in the reticle, the reticle to be used next and the used reticle are carried out at the same time. In addition, measurement of the device state using a test reticle
It is started by an operator between lots.

[0006]

In order to maintain the performance of the semiconductor exposure apparatus at a high level, the state of the apparatus is periodically measured, and various parameters for controlling the state of the apparatus are corrected based on the measurement result. In order to perform this measurement, a test reticle having a specific measurement pattern must be carried into the reticle stage, and after measurement, carried out from the reticle stage. On the other hand, an LSI represented by a semiconductor memory
Since the integration and miniaturization of the above elements are continuously progressing, the performance required for a semiconductor exposure apparatus is also improving.
As a result, it is necessary to increase the frequency of the measurement and correction in order to maintain the performance of the device at a higher level. When the frequency of the measurement is increased, the frequency of loading and unloading of the test reticle to and from the reticle stage increases, which causes a significant decrease in throughput. In addition, as the frequency of measurement using the test reticle increases, the operation for recognizing the arrival of the measurement time and activating the measurement by the operator is repeatedly performed, which results in forcing the operator to always wait and for the operator to perform the operation. Since the total time from the recognition of the arrival of the measurement timing to the completion of the operation of starting the measurement also increases, the effect of this on the throughput cannot be ignored.

An object of the present invention is to minimize a decrease in throughput due to an increase in the frequency of loading and unloading of test reticles in an exposure apparatus and a device manufacturing method in view of the above-mentioned problems of the prior art.

[0008]

According to the present invention, there is provided an original stage for holding an original having an exposure pattern at an exposure position, and a carrier for carrying the original in and out of the original stage. And a rotatable original loading / unloading arm having an original holding portion capable of holding the original at two positions symmetrical with respect to the center of rotation on the transport path, and a rotational drive for rotating the original transport arm. Means, whereby the loading and unloading of the original to and from the original stage can be performed simultaneously.In the exposure apparatus, the original loading and unloading arm is on the same circumference around the rotation center and The image forming apparatus further includes an extended holding unit capable of holding the original at one or more positions that do not interfere with the original holding unit.

Further, in the device manufacturing method of the present invention, at the exposure position of the exposure apparatus, the original is transported by transport means for loading and unloading the original to and from an original stage holding an original having an exposure pattern. Performing the exposure, held in the original stage, in a device manufacturing method for measuring the state of the apparatus by a test original for measuring the state of the apparatus, the transport means,
On the transport path, there is provided a rotatable original loading / unloading arm having an original holding portion capable of holding an original at two locations symmetrical with respect to the center of rotation, and rotational driving means for driving the original to rotate. An extended holding unit capable of simultaneously loading and unloading the original, and capable of holding the original at one or more positions on the same circumference around the rotation center and not interfering with the original holding unit; In measuring the state of the apparatus, the test original held by the extension holding unit is supplied to the original stage and collected.

In this configuration, with respect to the procedure and time required for normal loading, unloading and replacing of the original, the original loading and unloading arm has the same function and performance as the conventional elevating and rotating arm, and a test is carried out on the extended holding section. By holding a frequently used master such as a reticle, when using the test reticle, the same lifting, rotation, lowering, etc. as the normal reticle loading / unloading by the master loading / unloading arm except for the rotation angle when using the test reticle. By the operation, the reticle on the original stage is carried out and the test reticle is carried into the original stage. Further, after the test reticle is used, the carry-out of the test reticle on the original stage and the carry-in of the reticle held in one of the two original holders are simultaneously performed by the same operation.

[0011]

In a preferred embodiment of the present invention, the carrying means carries the original into and out of the original stage with storage means for storing a plurality of originals. Further, the transfer means has a vertical drive mechanism for moving the original loading / unloading arm up and down, thereby transferring the original to the original loading / unloading arm.

Further, an interval time for executing the measurement of the device state using the test master is determined, and every time the interval time elapses, or the execution of the measurement of the device state using the test original is determined. It is determined whether or not to execute each exposure processing of the exposed substrates. Each time the processing of the determined number of exposed substrates is completed, the processing is performed before or next to the exposure processing of the next exposed substrate. Before the exposure processing of the lot, the test original held in the extension holding unit is carried into the original stage, the device accuracy is measured using the test original, and the test original is transferred to the extension holding unit. It collects and corrects each device control parameter based on the measurement result.

Alternatively, when a measurement / correction command is received from the host computer via communication means for communicating with a host computer for managing a manufacturing process in a factory, the exposure processing or the lot of the substrate to be exposed is executed. After the exposure process is completed, the test original held in the extension holding unit is carried into the original stage, the device accuracy is measured using the test original, and the test original is extended and held. And corrects each device control parameter based on the measurement result.

By causing the control means of the exposure apparatus to perform such an operation, measurement of the apparatus state and correction of each apparatus control parameter are performed without intervention of an operator. Preferably, the operation of transferring the original to the original holding portion and the extended holding portion in the original loading and unloading arm is the same except for the rotation angle of the original loading and unloading arm. Also,
The extension holder has the same structure as the original holder.

[0015]

【Example】

[Embodiment 1] FIG. 1 is a view best showing the features of the present invention. In FIG. 1, reference numeral 8 denotes a lifting / rotating arm having a mechanism for lifting and lowering and rotating in a horizontal direction;
a is the center of rotation of the lifting / rotating arm 8, 8b and 8c are reticle holding parts of the lifting / rotating arm 8, and 8d is a test reticle holding part of the lifting / rotating arm 8.

The test reticle mounted on the test reticle holding portion 8d is vertically moved up to a height not interfering with the reticle stage 7 during rotation of the arm.
After rotating by 90 ° in the direction (counterclockwise) and lowering to the original height, it moves to the reticle stage 7,
The device can be used for purposes such as measuring the device status. The test reticle moved to the reticle stage 7 raises the elevating / rotating arm 8 and performs CW rotation around the rotation center 8a.
By rotating it in the direction (clockwise) and then lowering it, it returns to its original state. In loading and unloading the test reticle to and from the reticle stage 7, the reticle on the reticle holder 8b is maintained as it is, and the reticle on the reticle stage is moved halfway through the reticle holder 8.
c, but is finally returned to the reticle stage 7. When loading and unloading a reticle to and from reticle stage 7 for normal exposure processing using reticle holding units 8b and 8c, the test reticle installed in test reticle holding unit 8d is maintained as it is. You.

In this embodiment, the lifting / rotating arm 6 shown in the prior art is modified to have a test reticle holding portion 8d, and the test reticle holding portion 8d is provided with a reticle stage 7 for a rotating mechanism. This can be realized by adding a means for recognizing that the above predetermined position has been reached. Further, by moving the test reticle holding unit 8d to the position of the reticle holding unit in FIG. 4, the test reticle mounted on the test reticle holding unit 8d can be replaced by the conventional transporting means except for the lifting / lowering / rotating arm. It is possible.

FIG. 2 is a flowchart showing a process in which the control means of the exposure apparatus executes measurement and correction using a test reticle at a preset frequency without operator intervention in this configuration. It is assumed that the interval time T and the number W of wafers for determining the frequency of the measurement and correction are set together with other exposure sequence control parameters prior to the exposure processing.

When the first exposure process after the interval time T for determining the frequency of measurement / correction or the number W of wafers is changed in advance is started (step S1), a timer for measuring the elapsed time is reset immediately after that (step S1). Step S2) and resetting of a counter for recording and adding the number of processed wafers w (step S3) are executed.

In the following steps S4 to S10, 1
This is a process that is repeatedly executed for each process of one wafer. That is, first, it is determined whether or not to start processing for a new lot (step S4). If it is determined that the slot is not a new slot, the process directly proceeds to step S6, and if it is determined that the slot is a new slot, it is necessary. After the used reticle is exchanged (step S5), the process proceeds to step S6.
In step S6, a series of exposure processing for one wafer is executed, and thereafter, a counter of the number of processed wafers w is incremented by one.
Is added (step S7), and it is determined whether or not the exposure processing is completed (step S8). When it is determined that the exposure processing is completed, the exposure processing is completed. However, when the exposure processing is not completed, whether the elapsed time of the timer is longer than the interval time T is determined. It is determined whether or not it has exceeded (steps S9, S1
0). If the elapsed time of the timer is greater than the interval time T, or if the number of processed wafers w is greater than the number of wafers W, the test reticle is loaded into the reticle stage and the reticle is unloaded from the reticle stage (step S11). The measurement of the device state using the test reticle and the correction of the device control parameters based on the measurement result (Step S12), the collection of the test reticle, and the transfer of the reticle carried out in Step S11 to the reticle stage (Step S13). ,
Thereafter, the timer is reset (step S14) and the number of processed wafers is reset (step S15).

[Embodiment 2] FIG. 3 shows a second embodiment of the present invention, in which a first step of receiving a measurement / correction command sent from a host computer without intervention of an operator, and its reception. 9 is two flow charts showing a second step of measuring an apparatus state using a test reticle and updating an apparatus control parameter according to data.
The device configuration is the same as that described above. First step and second
Are performed in parallel.

In the first step, "reception and recording of a measurement / correction command", when the control means of the exposure apparatus receives the measurement / correction command sent from the host computer (step S31), it receives the command. The fact that the command has been recorded is recorded, and the measurement conditions received with the command are stored (step S32).

In the second step, the "measurement / correction step based on a command from the host computer", the control means of the exposure apparatus starts arbitrary exposure processing (step S3).
3) Unless the measurement / correction command is recorded (step S34), the processing of steps S35 to S38 is repeated for each wafer. That is, first, it is determined whether or not to start processing for a new lot (step S35). If it is determined that the current slot is not a new slot, the process directly proceeds to step S37. If it is determined that the current slot is a new slot, it is necessary. After the used reticle is replaced (step S36)
Proceed to step S37. In step S37, a series of exposure processing for one wafer is executed, and thereafter, it is determined whether or not the exposure processing is completed (step S38).
When it is determined that the exposure processing is completed, the exposure processing is completed. However, when the exposure processing is not completed, the process returns to step S34, and the same processing is performed on the next wafer.

If it is determined in step S34 that the measurement / correction command is recorded, the test reticle is carried into the reticle stage, the reticle is carried out on the reticle stage (step S39), and the state of the apparatus using the test reticle is changed. Measurement and correction of the device control parameters based on the measurement result (Step S40), collection of the test reticle, and loading of the reticle carried out in Step S39 into the reticle stage (Step S41).
After that, the recording of the measurement / correction command is erased (step S42), and the measurement / correction result is reported to the host computer (step S43), and step S35 is performed.
Move to

Next, a description will be given of an example of manufacturing a device that can use this exposure apparatus. FIG. 7 shows a micro device (I
1 shows a flow of manufacturing semiconductor chips such as C and LSI, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, and the like. In step 31 (circuit design), the circuit of the semiconductor device is designed. Step 32 is a process for making a mask on the basis of the circuit pattern design. on the other hand,
In step 33 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 34 (wafer process) is referred to as a preprocess, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 35 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer prepared in step 34, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. Step 36 (inspection)
Then, inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 35 are performed. Through these steps, a semiconductor device is completed and shipped (step 37).

FIG. 8 shows a detailed flow of the above wafer process. Step 41 (oxidation) oxidizes the wafer's surface. In step 42 (CVD), an insulating film is formed on the wafer surface. In step 43 (electrode formation), electrodes are formed on the wafer by vapor deposition. In step 44 (ion implantation), ions are implanted into the wafer. Step 45
In (resist processing), a photosensitive agent is applied to the wafer. Step 46 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. In step 47 (developing), the exposed wafer is developed. In step 48 (etching), portions other than the developed resist image are removed. In step 49 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer. By using this manufacturing method, a highly integrated semiconductor device, which was conventionally difficult to manufacture, can be manufactured at low cost.

[0027]

As described above, according to the present invention, the original carrying-in / out arm holds the original at one or more positions on the same circumference centered on the rotation center and which does not interfere with the original holding part. To have a further possible expansion holder,
To reduce the time required for loading and unloading the test master to and from the master stage, and to suppress the decrease in throughput due to the loading and unloading of the test master, in response to the increase in the frequency of measuring the device status using the test master. it can.

Further, an interval time for executing the measurement of the apparatus state using the test master is determined, and each time the interval time elapses, the apparatus state is measured and the apparatus control parameters are corrected. Measurement and correction can be performed at appropriate time intervals, and changes in the state of the apparatus over time can be suppressed to a certain range.

Further, it is determined how many times the substrate to be exposed is to be measured by using the test master for each exposure process of the substrate to be exposed, and each time the processing of the determined number of substrates to be exposed is completed. In addition, since the measurement of the apparatus state and the correction of the apparatus control parameters are performed, the measurement and the correction can be executed for each appropriate number of wafers, and the change in the apparatus state due to the processing amount of the wafer is suppressed to a certain range. be able to.

Further, when a measurement / correction command is received via the communication means from the host computer through communication with a host computer which controls a manufacturing process in a factory, the test master is used at an appropriate break of exposure processing. Since the measurement of the device status and the correction of the device control parameters are performed, the management of the device status by the host computer becomes easy.

[Brief description of the drawings]

FIG. 1 is a view for explaining a lifting / lowering / rotating arm in an exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a flowchart of processing steps in the exposure apparatus of FIG.

FIG. 3 is a flowchart of processing steps according to a second embodiment of the present invention.

FIG. 4 is a perspective view illustrating an entire reticle transport system in a conventional example.

FIG. 5 is a top view of a lifting / lowering arm in a conventional example.

FIG. 6 is a sectional view taken along line AB in FIG. 5;

FIG. 7 is a flowchart showing a flow of manufacturing a micro device that can be manufactured by the exposure apparatus described with reference to FIG.

FIG. 8 is a flowchart showing a detailed flow of a wafer process in FIG. 7;

[Explanation of symbols]

1A: Standard reticle cassette library, 1B: Extended reticle cassette library, 2: Reticle cassette robot, 3: Relay storage unit, 4: Reticle robot,
5: lifter, 6: conventional elevating / rotating arm, 7: reticle stage, 8: elevating / rotating arm according to the present invention.

Claims (13)

[Claims] An exposure stage includes an original stage for holding an original having an exposure pattern, and transport means for loading and unloading the original to and from the original stage. , A rotatable original loading / unloading arm having an original holding portion capable of holding the original at two locations symmetrical with respect to the center of rotation, and rotation driving means for rotating the original loading / unloading arm, thereby loading the original onto the original stage. And the unloading arm can be performed at the same time. In the exposure apparatus, the original loading / unloading arm is provided at one or more positions on the same circumference around the rotation center and not interfering with the original holding unit. An exposure apparatus further comprising an extended holding unit capable of holding an original. 2. A test original which is held on the original stage and which measures the state of the apparatus by a test original for measuring the state of the apparatus, wherein the test original held by the extended holding unit is provided. 2. An exposure apparatus according to claim 1, wherein said substrate is supplied to and recovered from said original stage. 3. The apparatus according to claim 1, wherein the transporting means carries in and out the original to and from an original stage with storage means for storing a plurality of originals. Exposure equipment. 4. The apparatus according to claim 1, wherein said transport means has an up-down drive mechanism for vertically moving said original loading / unloading arm, thereby transferring the original to said original loading / unloading arm. The exposure apparatus according to any one of claims 1 to 3, 5. An interval time for executing a measurement of an apparatus state using the test master is determined, and each time the interval time elapses, before or next to exposure processing of a substrate to be exposed next. Before the exposure processing of the lot to be performed, the test original held in the extension holding unit is carried into the original stage, the accuracy of the apparatus is measured using the test original, and the test original is placed in the extension holding unit. 3. The exposure apparatus according to claim 2, further comprising a control unit that collects the data and corrects each device control parameter based on the measurement result. 6. A method for determining the number of substrates to be exposed to be executed for each exposure process on the apparatus using the test master, and terminating the processing of the determined number of substrates to be exposed. Each time, before the exposure processing of the substrate to be exposed next or before the exposure processing of the lot to be processed next, the test master held in the extended holding unit is carried into the master stage, and the test master is loaded. Measure the device accuracy using the original plate,
3. The exposure apparatus according to claim 2, further comprising a control unit that collects the test master in the extension holding unit and corrects each device control parameter based on the measurement result. 7. A communication device for communicating with a host computer for managing a manufacturing process in a factory, and when a measurement / correction command is received from the host computer via the communication device, an exposure process for a substrate to be exposed is executed. Or after the exposure process of the lot is completed, the test master held in the extended holding unit is carried into the master stage, and the device accuracy is measured using the test master, and the test master is used as the test master. 3. The exposure apparatus according to claim 2, further comprising a control unit that collects the data in the extension holding unit and corrects each device control parameter based on the measurement result. 8. The operation of transferring an original to and from the original holding unit and the extended holding unit in the original loading and unloading arm is the same except for the rotation angle of the original loading and unloading arm. The exposure apparatus according to any one of the above. 9. The exposure apparatus according to claim 1, wherein the extension holding unit has the same structure as the original holding unit. 10. An exposure apparatus, wherein the original is transported to and transported from an original stage holding an original having an exposure pattern by a transport means for loading and unloading the original at an exposure position of the exposure apparatus. In the device manufacturing method for measuring the state of the apparatus by using a test original for measuring the state of the apparatus held on the device, the transport unit may include two originals at two locations symmetrical with respect to the rotation center on the transport path. A rotatable original loading / unloading arm having an original holding portion capable of holding the original, and a rotation driving means for rotating the original loading / unloading arm, whereby the loading / unloading of the original to / from the original stage can be performed simultaneously. An original at one or more positions on the same circumference around the rotation center and not interfering with the original holding portion. Is further provided, and when measuring the state of the apparatus, supplying and collecting the test master held in the expansion holder to the original stage. Device manufacturing method. 11. An interval time for executing a measurement of an apparatus state using the test master is determined, and each time the interval time elapses, before or next to exposure processing of a substrate to be exposed next. Before the exposure processing of the lot to be performed, the test master held in the extended holding unit is carried into the master stage, and the device accuracy is measured using the test master,
11. The device manufacturing method according to claim 10, wherein the test master is collected in the extension holding unit, and each device control parameter is corrected based on the measurement result. 12. A method for determining the number of substrates to be exposed to be performed for each exposure process by using the test master to perform measurement of an apparatus state, and terminating the processing of the determined number of substrates to be exposed. Each time, before the exposure processing of the substrate to be exposed next or before the exposure processing of the lot to be processed next, the test master held in the extended holding unit is carried into the master stage, and the test master is loaded. 11. The device manufacturing method according to claim 10, wherein the accuracy of the apparatus is measured using an original, the test original is collected in the extension holding unit, and each apparatus control parameter is corrected based on the measurement result. 13. Communicating with a host computer for controlling a manufacturing process in a factory and receiving a measurement / correction command from said host computer via said communication means,
After the exposure processing of the substrate to be exposed or the exposure processing of the lot being completed is completed, the test master held in the extended holding unit is loaded into the master stage, and the accuracy of the apparatus is reduced using the test master. 11. The device manufacturing method according to claim 10, wherein measurement is performed, the test master is collected in the extension holding unit, and each device control parameter is corrected based on the measurement result.