TW569324B - Method of drying after performing a semiconductor substrate cleaning process - Google Patents

Abstract

A method of drying after performing a semiconductor substrate cleaning process comprises, after performing the abovementioned cleaning process, and using two pipelines to separately introduce N2 gas and a mixture gas of N2 and IPA into a dryer to performing a drying treatment in order to remove residual moisture from the semiconductor substrate. The invention is characterized in that the IPA flow is reduced during the drying process.

Description

569324 Five technical steps Description of the invention (1) Technical field: ^ The invention relates to a method A for drying after a semiconductor substrate cleaning process, especially a method for drying steps after the semiconductor substrate is not eroded. Background of the Invention: In order to pursue faster operating speed and greater accumulation density, the research units and manufacturers of Integrity Road endeavor to design and manufacture smaller critical dimensions (CDs) and more silicon oxide layers. Thin components. The cleanliness of semiconductor substrates has been an important issue for semiconductor companies during the two or three decades of integrated circuit development. Especially after the integrated circuit manufacturing process has entered the field of deep sub-microns, with the attendant technical challenges, the cleanliness of the semiconductor substrate has a very important impact on the process rate. In semiconductor manufacturing, the main pollutants are particles, metals, organics, microroughness, and native silicon oxide (native oxide). The particles mainly come from the machine, the environment, deionized water, or chemicals, etc. 'Valley is liable to cause the collapse of the oxidized stone layer to decrease the voltage, the polycrystalline stone wire or the metal interconnects are bridged and short-circuited; Mainly from the machine, the environment, reactive ion etching (RIE), or chemicals' easy to cause the collapse of the oxide oxide layer to reduce the voltage, increase the interface leakage current, the initial voltage shift, etc .; organic matter usually comes from Residual photoresist, storage containers, or chemicals can cause changes in oxidation rates.

569324

The crystalline silicon wires or metal interconnects are found on semiconductor substrates. Part of the silicon oxide layer is caused by environmental moisture and the strength of the layer and the uniformity of the film thickness. The five pollutants described above will greatly affect the system The cleaning process is an important issue to reduce the above pollutants. Short circuit, etc .; Micro-roughness will make it worse by the original pickling solution; original deionized water will reduce the gate silicon oxide ’and increase the resistance of the contact window. Yield of the journey. Therefore, the use of effective 'has become a part of the semiconductor industry. After each cleaning process is completed, especially before the semiconductor substrate is sent into the furnace tube, the semiconductor substrate must be sent to a dryer to remove moisture using N and IPA. In order to avoid leaving water marks on the semiconductor substrate, the flow rate of N2 is about 50 SCCm 'and the flow rate of NJIPA is about 50 sccin, as shown in Figure 1. However, during the drying process, due to the residue of organic substances, In the subsequent high-temperature process, the above-mentioned residual organic substances chemically interact with the semiconductor substrate to cause pitting on the surface of the semiconductor substrate. Therefore, a new method of drying the semiconductor substrate after the cleaning process has been developed, and While removing the moisture on the surface of the semiconductor substrate, it will not erode the semiconductor substrate, which has become an important issue for integrated circuit industry.

SUMMARY OF THE INVENTION: The main object of the present invention is to provide a method for a drying step after a washing process. The invention discloses a drying step after a semiconductor substrate cleaning process is performed.

Page 5 569324 V. Description of the invention (3)

After performing the cleaning process, two tubes of N gas and N plus IPA gas are introduced into a dryer to perform the drying, and the residual moisture on the semiconductor substrate is removed stepwise. The technical point of the present invention is to reduce the flow rate of I PA during the drying step. It is preferred that the method of reducing the flow rate of I PA is to fix the flow rate of N ammonia gas and decrease the flow rate of N 2+ I PA gas with time. Preferably, the method of reducing the flow rate of IPA is to decrease the flow rate of N ammonia body and the flow rate of N plus IPA gas according to time. Preferably, the method of reducing the flow rate of I PA is to change the pipeline carrying N plus IPA gas, and connect the pipeline carrying N plus IPA gas to the pipeline carrying N gas. The technical focus of the present invention is to change the process parameters of the drying step of the cleaning process, and in the third embodiment, to change the pipeline configured by the dryer, the concentration of I PA in the drying step can be effectively reduced. In this way, I PA can be prevented from remaining on the semiconductor substrate after the drying step of the cleaning process. Drawing number description 1 0-dryer

The invention relates to a drying method and device for a semiconductor substrate cleaning process. The invention can be applied to the cleaning of various processes using silicon as a material, including semiconductor processes, thin film transistor-liquid crystal display (TFT-LCD) processes, and the like. First, please refer to FIG. 2 ’, which is a schematic diagram of the dryer and its configured pipelines.

Page 6 569324 V. Description of the invention (4) Figure. The dryer 10 is provided with two pipelines, one of which is used to introduce the N-body, and the other is to use N and: to guide the gas to introduce I PA. Next, please refer to FIG. 3, which is a graph showing a change in a gas flow rate in a drying step after a cleaning process in the first embodiment of the present invention. In order to avoid the residue of organic substances in the drying step after the cleaning process, the first embodiment of the present invention fixes the flow rate of the N miao body and decreases the flow rate of the N 2+ IPA gas with time. The flow rate of N2 + IPA gas decreases from 50 sccm to 40 sccm to between 25 sccm and 15 sccm within 1 minute to 10 minutes. The optimal flow rate of N gas is 50 sccm, and the optimal flow rate of N2 + IPA gas is a linear decrease from 50 s c c m to 20 s c c m within 5 minutes. Next, please refer to FIG. 4, which is a graph showing a change in a gas flow rate in a dry step after a cleaning process in a second embodiment of the present invention. In order to avoid the residue of organic substances in the drying step after the cleaning process, the second embodiment of the present invention decreases the flow rate of N gas and the flow rate of N 2+ IPA gas according to time, wherein the flow rate of N 2 gas is from 1 minute to 10 The time in minutes is from 50 scc m to 40 sccm to between 2 5 sccm and 15 sccm. The flow of N 2+ IPA gas is between 50 scc m in 1 minute to 10 minutes. And 40 sccm to between 25 sccm and 15 sccm. The optimal flow rate of N gas is reduced from 50sccmi to 20 sccm in 5 minutes, and the optimal flow rate of NAIPA gas is decreased from 50 sccm to 20 seem in 5 minutes. ○ Please refer to Figure 5 below, where Figure 5A is a schematic diagram of the dryer and its configuration pipeline used in the third embodiment of the present invention, and Figure 5B is

569324 V. Description of the invention (5)

Change diagram of gas flow rate in the drying step after the cleaning process in the third embodiment of the invention. In order to avoid the residue of organic substances in the drying step of the cleaning process, the third embodiment of the invention will not directly connect the pipeline carrying IPA with N helium to the dryer 10, but connect to the carrying N fishing The pipeline can effectively dilute the concentration of IPA, where the flow rate of n gas is between 50 sccm and 40 seem, and the flow rate of n2 + IPA gas is between 50 sccm and 40 sccm within 1 minute to 10 minutes. Decreased between 25 sccm and 15 sccm. Among them, the optimal flow rate of N2 gas is 50 sccm, and the optimal flow rate of N2 + IPA gas is 50 sccm to 5 0 within 5 minutes. In addition, in the third embodiment, the flow rate of N gas and the The flow rate of N 2+ IPA gas decreases with time, and the flow rate of N helium gas decreases from 50 sccm and 40 sccm to between 2 5 seem and 15 seem within 1 minute to 10 minutes. In the meantime, the flow rate of N2 + IPA gas decreases from 50 sccm to 40 sccm to between 25 sccm and 15 sccm in a period of 1 minute to 10 minutes. Among them, the optimal flow rate of N ammonia body is from 50sccm to 20sccm within 5 minutes, and the optimal flow rate of NJIPA gas is from 50sccm to 20sccm within 5 minutes. The technical focus of the present invention is to change the process parameters of the drying step of the cleaning process and change the pipeline configured by the dryer in the third embodiment, which can effectively reduce the concentration of IPA in the drying step. In this way, I PA can be prevented from remaining on the semiconductor substrate after the drying step of the cleaning process. The above is a detailed description of the present invention using preferred embodiments, but not limiting the scope of the present invention ', and those skilled in the art will understand that it is appropriate

Page 8 569324 V. Description of the invention (6) Making minor changes and adjustments will still not lose the essence of the invention, nor depart from the spirit and scope of the invention.

I1HH 569324 Brief description of the diagram Brief description of the diagram: Figure 1 is a diagram showing the change of the gas flow rate in the drying step after the cleaning process in the conventional technology. Figure 2 is a schematic diagram of the dryer and its configured pipelines. Fig. 3 is a graph showing a change in a gas flow rate during a drying step after a cleaning process in the first embodiment of the present invention. Fig. 4 is a graph showing a change in a gas flow rate during a drying step after a cleaning process in a second embodiment of the present invention.

Fig. 5A is a schematic diagram of the dryer and its configuration pipeline used in the third embodiment of the present invention. Fig. 5B is a graph showing the change of the gas flow rate in the drying step after the cleaning process in the third embodiment of the present invention.

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Claims (1)

569324 6. Scope of patent application Patent scope: 1. A method for performing a drying step after a semiconductor substrate cleaning process. After performing the cleaning process, two pipelines are used to respectively introduce N helium and N IPA gas into a dryer. In the method, the drying step is performed to remove residual moisture on the semiconductor substrate; and it is characterized in that when the drying step is performed, the flow rate of IPA is reduced. 2 · The method for performing the drying step after the semiconductor substrate cleaning process as described in item 1 of the scope of the patent application, wherein the method for reducing the flow rate of IPA is to fix the flow rate of N ammonia and fix the N 2+ 1 PA gas. Traffic decreases over time. 3. The method for performing the drying step after the semiconductor substrate cleaning process as described in item 2 of the scope of the patent application, wherein the flow rate of N gas is between 50 sccm and 40 sccm, and the flow rate of N ammonia body plus IPA is 1 minute. Within 10 minutes from 50 sccm and 40 scc in to between 2 5 sccm and 15 sccm 0 4. After the semiconductor substrate cleaning process as described in item 1 of the scope of patent application The method of drying step, wherein the method of reducing the flow rate of 1 PA is to decrease the flow rate of N gas and the flow rate of N plus IPA gas according to time. 5. The method for performing the drying step after the semiconductor substrate cleaning process as described in item 4 of the scope of the patent application, wherein the flow rate of the N ammonia body is 1 minute 569324 6. The range of application for patents decreases from 50 sccm and 40 seem to between 2 5 sccm and 15 sccm within 10 minutes, and the flow rate of the N 2+ IPA gas is from 1 minute to 10 The time in minutes decreases from between 50 sccm and 40 sccm to between 25 sccm and 15 sccm. 6 · The method for performing the drying step after the semiconductor substrate cleaning process as described in item 1 of the scope of the patent application, wherein the method of reducing the flow rate of 1 p A is to change the pipeline carrying N plus I PA gas, so that The pipeline carrying N plus I PA gas is connected to the pipeline carrying N 2 gas. 7 · The method for performing the drying step after the semiconductor substrate cleaning process as described in item 6 of the scope of the patent application, wherein the flow rate of the N ammonia body is fixed and the flow rate of the N plus IPA gas decreases with time * ° 8 The method for performing the drying step after the semiconductor substrate cleaning process according to item 7 of the scope of the patent application, wherein the flow rate of the ammonia gas is between 50 sccm and 40 sccm, and the flow rate of N such as IPA gas is between The time from 1 to 10 minutes decreases from 50 sccm to 40 sccm to between 25 sccm and 15 sccm. 9. The method of performing the drying step after the semiconductor substrate cleaning process according to item 6 of the scope of the patent application, wherein the flow rate of the N gas and the flow rate of the N 2 plus I P A gas are extinguished with time * ° Page 12 569324 VI. Patent Application Range 10 · The method of performing the drying step after the semiconductor substrate cleaning process as described in item 9 of the patent application range, wherein the flow rate of the N ammonia body is between 1 minute and 10 minutes. The time decreases from 50 sccm to 40 sccm to between 25 sccm and 15 sccm, and the flow rate of the N plus IpA gas decreases from 50 sccm to 40 sccm to 25 sccm and 1 between 5sccm. 13th Tribute