JPH09171955A - Method and system for processing resist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a system for processing resist wherein a highly precise and convenient accuracy control can be carried out in a step for coating a semiconductor wafer with resist or SOG. SOLUTION: Additional jetting pressure is measured and monitored, along with the jetting and flow rate, for every jetting or lot and the jetting pressure or the time is regulated automatically based on the measurements such that a set jetting is not deviated. Consequently, fluctuation of jetting is suppressed and fluctuation in the thickness of coating due to difference of viscosity caused by the difference of production lot number of resist bottle 1 is accommodated. Alternatively, fluctuation in the thickness of coating can be suppressed among the lots of semiconductor wafer 6 or among the wafers 6. Furthermore, periodical confirmation of thickness by the operator is not required and highly precise and convenient coating of resist or SOG can be realized resulting in significant enhancement of dimensional accuracy of the pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for manufacturing a semiconductor integrated circuit, particularly a resist or SO on a semiconductor wafer.
The present invention relates to a device for applying G or the like.

[0002]

2. Description of the Related Art As a prior art of a resist coating apparatus, it is shown in the patent of publication number 06-267813. A schematic diagram of the conventional device is shown in FIG. When applying the resist to the surface of the semiconductor wafer 2, the semiconductor wafer 2 is fixed to the chuck by the vacuum chuck 3 and is rotated by the motor 4, or the resist is discharged from the discharge nozzle 1 while it is stopped. The resist is discharged by pushing out the resist from the pump 5 by applying pressure to the diaphragm 6 in the pump 5 to push it up.
After the ejection, the semiconductor wafer 2 is rotated at a desired rotation speed for a certain period of time to make the resist have a desired coating film thickness. Resist bottle 8 installed in the resist coating device
Therefore, when changing to a resist bottle whose manufacturing lot number is different from the previous one, in order to obtain the same coating film thickness as before changing, the resist was changed and the number of rotations was adjusted. In addition, it is necessary to regularly check the coating film thickness.

[0003]

This is because when the resist production lots are different, even if the resists have the same viscosity, a slight change in the applied film thickness occurs due to some influence in the process of applying the resist onto the semiconductor wafer. In addition, the discharge amount changes as the amount of resist in the resist bottle decreases. For this reason, it is necessary to confirm the coating film thickness after changing the resist, etc., and there is a problem that workability deteriorates. Further, since it is not constantly monitored, the coating film thickness varies from lot to lot. For a semiconductor wafer that has not been applied in a desired film thickness, it is necessary to remove the resist and apply it again.

Therefore, the present inventor has found that there are various problems such as variations in the pattern size formed by the resist and a desired pattern size cannot be obtained.

An object of the present invention is to provide a resist processing apparatus capable of performing simple and general-purpose management.

[0006]

Means for Solving the Problems A resist, SO 2 and SO 3 are formed on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged.
A resist processing apparatus for applying G or the like has means for detecting the discharge flow rate and discharge pressure at that time even if the viscosity of the resist varies by several cp depending on the manufacturing lot, and means for controlling the discharge flow rate and discharge pressure. It has a function of controlling the coating film thickness to a constant film thickness by having a means for adjusting either or both of the discharge flow rate and the discharge pressure based on the detection result.

Further, in a resist processing apparatus for coating a resist on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer are monitored at the time of discharge to monitor the resist semiconductor wafer. It is characterized by having a function of adjusting the discharge time at the time of the next discharge so that the discharge flow rate to the surface is always constant.

In a resist processing apparatus for coating a resist on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge amount of the resist and the discharge pressure at that time are measured at the time of dummy dispensing, and the resist on the surface of the semiconductor wafer is measured. It is characterized by having a function of adjusting the discharge pressure so that the discharge flow rate becomes constant.

In a resist processing apparatus for coating a resist on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge amount of resist and the discharge pressure at that time are measured at the time of dummy dispensing, and a constant discharge amount is obtained. Is characterized by having a function of adjusting the discharge time.

In a resist processing apparatus for applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, by making the amount of resist discharged onto the surface of the semiconductor wafer constant, the dimensional variation after patterning can be made in a range. The feature is that it can be suppressed within 0.02μ.

In a resist processing method for coating a resist on a surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer are monitored at the time of discharging, and the resist is applied to the surface of the semiconductor wafer. The discharge time of the next discharge is adjusted so that the discharge flow rate of is always constant.

In a resist processing method for applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharging pressure and the discharging flow rate onto the surface of the semiconductor wafer are monitored at the time of discharging, and the resist is applied to the surface of the semiconductor wafer. The feature is that the discharge pressure at the time of the next discharge is adjusted so that the discharge flow rate of is always constant.

In a resist processing method for applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge pressure and the discharge flow rate of the resist are measured during dummy dispensing to discharge the resist onto the surface of the semiconductor wafer. The feature is that the discharge pressure is adjusted so that the flow rate becomes constant.

In a resist processing method for applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the resist pressure and the discharge flow rate of the resist onto the surface of the semiconductor wafer are monitored at the time of discharge to monitor the resist semiconductor wafer. The feature is that the ejection time for the next ejection is adjusted so that the ejection flow rate to the surface becomes constant.

In a resist processing method of applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge pressure and the discharge flow rate of the resist onto the surface of the semiconductor wafer are monitored at the time of discharge to monitor the resist semiconductor wafer. The feature is that the discharge pressure at the time of the next discharge is adjusted so that the discharge flow rate to the surface becomes constant.

In a resist processing method of applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge amount of the resist and the discharge pressure at that time are measured at the time of dummy dispensing, and a constant discharge amount is obtained. In addition, the discharge pressure is adjusted.

[0017]

According to the present invention, the discharge amount and the discharge pressure of the resist are measured and controlled, whereby the discharge amount onto the surface of the semiconductor wafer can be made constant at all times. Moreover, since the measurement is performed in real time, the variation in the coating film thickness between lots can be reduced, and the dimensional accuracy can be dramatically improved.

Therefore, conventionally, it was necessary to periodically measure the coating film thickness of the resist and adjust it so as to obtain a desired film thickness by the number of rotations of the semiconductor wafer. It is possible to manage with high accuracy. Therefore, the operation rate can be improved by reducing the down time of the resist coating device.

Along with this, the dimensional accuracy of the pattern formed on the semiconductor wafer can be improved.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail based on Examples.

FIG. 1 is a diagram showing the basic construction of a resist processing apparatus used for resist coating in the first embodiment of the present invention. A resist 12 is contained in the resist bottle 1, and the resist 12 is filled in a pipe 13 connecting the resist bottle 1 and the discharge nozzle 5. This is pump A
By applying pressure by IR2, the resist 12 is extruded from the pump 3, ejected from the ejection nozzle 5 through the filter 4 onto the wafer 6. At the time of discharging, the wafer 6 is vacuum chucked by the spin chuck 7 and rotated by the motor 8. After the resist is discharged, the wafer 6 reaches a predetermined rotation speed and is applied with a desired resist application film thickness. Here, when the resist 12 is ejected from the ejection nozzle 5, the AIR 12 is ejected.
The pressure in the pump generated by the pressure gauge 11 is monitored by a pressure gauge 11, and the flow rate of the resist 12 passing through the discharge nozzle 5 as a result of applying this pressure at the same time, in other words, the amount of the resist 12 discharged onto the wafer 6. , Are monitored by the flow sensor 10. The above operation is performed for each ejection operation.

Here, the discharge amount of the resist 12 is 3 ± 0.1 cc for 3 seconds, and the discharge pressure at this time is 0.5 kg.
Set to f / cm ² . When pressure is applied from the AIR 2 and the resist is discharged from the discharge nozzle 5, the flow rate sensor 10 measures the flow rate of the resist that has passed through the discharge nozzle 5 during this period. When the measured flow rate at this time is the set value of 3 cc ± 0.1 cc, the same discharge pressure as in the main measurement is applied in the next discharge. However, when the measured flow rate is less than the set value, as the first method, the next resist discharge operation is performed by applying a discharge pressure that is a fixed amount higher than the discharge pressure at the time of the next resist discharge. . As a second method, in order to keep the ejection amount at the next ejection within the set value, the ejection time is made longer than the set time, and the total ejection amount is adjusted to the set value, and the next ejection is adjusted. Take action.

Alternatively, when the measured flow rate is larger than the set value, the reverse operation is performed.

The relationship between the discharge pressure, the discharge time, and the discharge amount is known in advance as a linear approximation by the resist processing apparatus (the relationship between the discharge pressure and the discharge time with respect to the discharge amount depends on the lot, and the slope of the linear approximation is If the value of the Y-intercept changes constantly, the data in the ejection operation is refreshed at any time, and the ejection pressure or the ejection time for the next ejection operation is determined based on the latest 20 data.

In this way, in each discharge operation, the discharge amount and discharge pressure at that time are monitored, and the resist discharge amount for the next discharge is adjusted to be constant.

Next, FIG. 2 shows an outline of a resist processing apparatus used for resist coating in the second embodiment of the present invention. A resist 15 is filled in a pipe 19 connecting the resist bottle 14 and the discharge nozzle 27. The resist 15 is extruded by the pressure applied by the AIR 18 in the pump 16 and ejected from the ejection nozzle 27. At the time of discharging, the discharging nozzle is located on the center of the wafer 25 fixed to the spin chuck 26, the resist 15 is discharged at this position, and the wafer 25 rotates at a predetermined rotation speed to obtain a desired resist film thickness. . Here, if air bubbles generated in the pipe are caught during ejection, the coating becomes uneven. Therefore, before the resist 15 is ejected onto the wafer 25, the ejection nozzle 27 is provided in a housing installed next to the application cup 29. Is waiting, and the dummy dispense is performed here to remove the air bubbles in the pipe 19. This operation can be freely set at the beginning of the lot or before each ejection. Here, it is set as the beginning of the lot. Next to the coater cup 29, there is a housing 13 for waiting a discharge nozzle and performing dummy dispensing. Inside the housing, a liquid reservoir cup 22 for measuring the amount of dummy dispense, a liquid level sensor 21 corresponding to the liquid reservoir cup 22, and a valve 24 for discharging the resist accumulated in the liquid reservoir cup to the drain. Nozzle 3 in which piping 23 branched the back surface cleaning liquid for cleaning the liquid reservoir cup
0 is set. While the discharge nozzle 27 is on standby in the housing, the discharge nozzle 27 is located on the liquid storage cup 22. Here, the discharge nozzle 27 is in the housing 28 until the wafer 25 at the top of the lot is in the coater cup 29, and a dummy dispense is performed immediately before the wafer 25 enters the coater cup 29. At this time, the dispensed resist accumulates in the liquid reservoir cup 22. The liquid level of the accumulated resist is measured by the liquid level sensor. The liquid level sensor 21 has three stages, and if the liquid level is within the lower and upper sensor ranges, the amount of resist discharge is set. The pressure gauge 17 measures the discharge pressure when the dummy dispensing is performed. When the liquid level exceeds the upper level liquid level sensor, the discharge pressure is reduced. Then, the dummy dispensing is performed again, the liquid level of the resist accumulated in the liquid reservoir cup 22 is measured, and it is confirmed whether the liquid level is present in the liquid level sensor. In addition, the dummy dispensing is performed once, the valve 24 is opened after the liquid level is measured, and the back surface cleaning liquid is discharged from the nozzle to clean the inside of the liquid reservoir cup,
Waste liquid is drained to the drain through the drain pipe. Then, the valve 24 is closed and the next dummy dispense is performed. This is repeated until the liquid level is formed in the liquid level sensor.

Similarly, there is also a method of adjusting the discharge time within the standard by adjusting the discharge time with the same discharge pressure.

After that, the discharge nozzle 27 enters the coater cup 29 and moves onto the wafer 25 fixed on the spin chuck 26, and the resist is discharged from the discharge nozzle 27 at the determined discharge pressure.

Thus, according to the method of this embodiment, the discharge amount of the resist can be constantly controlled and the resist coating film thickness becomes constant. For this reason, it is not necessary to periodically check the coating film pressure, and the down time of the resist processing apparatus is shortened, and the operating rate is greatly improved. In addition, since the resist coating film thickness can be controlled and managed easily and accurately, it is possible to greatly reduce the variation in the resist coating film thickness between lot-to-lot wafers, and as a result, to greatly improve the uniformity of pattern dimensions. Is possible.

In the above description, the description has been mainly based on the embodiment made by the present inventor, but the present invention is not limited to the above-mentioned embodiment. Application to chemicals other than resist,
Various modifications can be made without departing from the scope of the present invention, such as the discharge amount measurement frequency and the combination of the first embodiment and the second embodiment.

[0031]

As described in detail above, according to the present invention, the accuracy and reproducibility of the resist coating film thickness can be greatly improved, and the resist processing apparatus can be managed simply and accurately.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a resist processing apparatus showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of a resist processing apparatus showing an embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional resist processing apparatus.

[Explanation of symbols]

 1 ... Resist bottle 2 ... AIR 3 ... Pump 4 ... Filter 5 ... Discharge nozzle 6 ... Semiconductor wafer 7 ... Spin chuck 8 ... Motor 9 ... Coater cup 10 ... Flow rate sensor 11 ... Pressure gauge 12 ... Resist 13 ... Piping 14 ... Resist bottle 15 ... Resist 16 ... Pump 17 ... Pressure gauge 18 ... AIR 19・ ・ ・ Piping 20 ・ ・ ・ Filter 21 ・ ・ ・ Liquid level sensor 22 ・ ・ ・ Liquid reservoir cup 23 ・ ・ ・ Drain piping 24 ・ ・ ・ Valve 25 ・ ・ ・ Semiconductor wafer 26 ・ ・ ・ Spin chuck 27 ・ ・ ・Discharge nozzle 28 ... Housing 29 ... Coater cup 30 ... Resist bottle 31 ... Resist 32 ... AIR 33 ... Pump 34 ... Piping 35 ... Discharge nozzle Sprue 36 ... Semiconductor wafer 37 ... Coater cup 38 ... Spin chuck 39 ... Motor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01L 21/316 H01L 21/316 G 21/30 564D

Claims (10)

[Claims] 1. In the step of applying a resist, SOG, etc. on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the viscosity of the resist is several cp depending on the manufacturing lot.
Even if it fluctuates, it has a means for detecting the discharge flow rate and the discharge pressure at that time, and a means for controlling the discharge flow rate and the discharge pressure, and either or both of the discharge flow rate and the discharge pressure based on the detection result. A resist processing apparatus having a function of controlling the coating film thickness to a constant film thickness by having a means for adjusting 2. In the step of applying a resist, SOG, or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer are monitored at the time of discharge to monitor the resist and SOG. 2. The resist processing apparatus according to claim 1, which has a function of adjusting a discharge time at the time of the next discharge so that the discharge flow rate onto the surface of the semiconductor wafer is always constant. 3. The resist and SOG are monitored by monitoring the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer during discharging in the step of applying the resist, SOG and the like on the surface of the semiconductor wafer on which a plurality of semiconductor devices are arranged. 2. The resist processing apparatus according to claim 1, which has a function of adjusting the discharge pressure at the time of the next discharge so that the discharge flow rate to the surface of the semiconductor wafer is always constant. 4. A constant discharge amount is measured by measuring the discharge amount of the resist and the discharge pressure at the time of dummy dispensing in the step of applying a resist, SOG, etc. on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged. A resist processing apparatus having the function of adjusting the discharge pressure so that 5. In a step of applying a resist, SOG or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge amount of the resist and the discharge pressure and the discharge time at that time are measured at a constant time during the dummy dispensing, and the results are constant. A resist processing apparatus having a function of adjusting a discharge time so that the discharge amount becomes. 6. A step of applying a resist to the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged,
By making the amount of resist discharged onto the surface of the semiconductor wafer constant, the variation in dimension after patterning can be reduced to 0.
The resist processing apparatus according to any one of claims 1 to 5, wherein the resist processing apparatus can be controlled within 02μ. 7. A method of applying a resist, SOG or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, wherein the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer are monitored at the time of discharge to monitor the resist and SOG. 2. The resist processing method, wherein the discharge time for the next discharge is adjusted so that the discharge flow rate on the surface of the semiconductor wafer is always constant. 8. A method of applying a resist, SOG, or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, by monitoring the discharge pressure and the discharge flow rate on the surface of the semiconductor wafer during discharge, A resist processing method, characterized in that the discharge pressure is adjusted so that the discharge flow rate to the nozzle is constant. 9. A method for applying a resist, SOG, or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, in which the discharge amount of the resist and the discharge pressure at that time are measured at the time of dummy dispensing to obtain a constant discharge amount. The resist processing method is characterized in that the discharge pressure is adjusted so that. 10. In a method of applying a resist, SOG, or the like on the surface of a semiconductor wafer on which a plurality of semiconductor devices are arranged, the discharge amount of resist and the discharge pressure and discharge time at that time are measured at a constant time during dummy dispensing. A resist processing method, wherein the discharge time is adjusted so that the discharge amount becomes.