CN108198771B - Flow control method and flow control device - Google Patents
Flow control method and flow control device Download PDFInfo
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- CN108198771B CN108198771B CN201711456622.5A CN201711456622A CN108198771B CN 108198771 B CN108198771 B CN 108198771B CN 201711456622 A CN201711456622 A CN 201711456622A CN 108198771 B CN108198771 B CN 108198771B
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- 238000000034 method Methods 0.000 title claims abstract description 60
- 238000009792 diffusion process Methods 0.000 claims abstract description 499
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 498
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 249
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 89
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 86
- 239000010703 silicon Substances 0.000 claims abstract description 86
- 239000007788 liquid Substances 0.000 claims description 36
- 238000003860 storage Methods 0.000 claims description 34
- 238000012360 testing method Methods 0.000 claims description 10
- ILAHWRKJUDSMFH-UHFFFAOYSA-N boron tribromide Chemical compound BrB(Br)Br ILAHWRKJUDSMFH-UHFFFAOYSA-N 0.000 claims description 6
- XHXFXVLFKHQFAL-UHFFFAOYSA-N phosphoryl trichloride Chemical group ClP(Cl)(Cl)=O XHXFXVLFKHQFAL-UHFFFAOYSA-N 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 235000012431 wafers Nutrition 0.000 description 67
- 238000010586 diagram Methods 0.000 description 6
- 238000012937 correction Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 3
- 238000011112 process operation Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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- H01L21/67253—Process monitoring, e.g. flow or thickness monitoring
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- H01L21/22—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities
- H01L21/228—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities using diffusion into or out of a solid from or into a liquid phase, e.g. alloy diffusion processes
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Abstract
The invention discloses a flow control method and a flow control device, wherein the flow control method comprises the following steps: acquiring the operation sequence of the current diffusion process in the diffusion furnace; obtaining a small nitrogen flow value required by the current executed diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process; and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process. The flow control method provided by the embodiment of the invention does not need manual adjustment, is beneficial to automatic production, solves the problems that in the prior art, the manpower cost is increased but the obtained silicon wafer sheet resistance fluctuation is large and the silicon wafer sheet resistance uniformity among batches is poor because small nitrogen with constant flow is introduced into the diffusion furnace and the temperature is adjusted by adjusting and propelling temperature, and achieves the purposes of saving the manpower cost and achieving good silicon wafer sheet resistance uniformity among batches.
Description
Technical Field
The present invention relates to flow control technologies, and in particular, to a flow control method and a flow control device.
Background
At present, solar energy is rapidly developed as a sustainable green energy source for replacing fossil fuel. PN junctions must be prepared in the process of preparing the solar cell, the thermal diffusion method is the most widely applied junction preparation method, and the doping uniformity directly influences the efficiency of the solar cell. In order to improve the efficiency of the solar cell, high sheet resistance (sheet resistance) becomes the development direction of the current diffusion process, which puts higher requirements on diffusion uniformity.
The existing diffusion process generally uses inert gas to carry a liquid source to dope a silicon wafer, the diffusion process comprises active diffusion and propulsion steps, the active diffusion method is that when a diffusion quartz tube is heated to the process temperature, fixed large nitrogen, small nitrogen and oxygen flow are introduced in a fixed time according to the process setting, and then the required square resistance value is achieved by adjusting the time or the temperature of the diffusion or propulsion step.
However, in the conventional diffusion method, the uniformity of the sheet resistance values obtained in batches is poor, and the time or temperature of the diffusion or propulsion step needs to be continuously adjusted by increasing manpower so as to obtain the sheet resistance values with good uniformity among batches, so that the manpower cost is increased.
Disclosure of Invention
The invention provides a flow control method and a flow control device, which aim to achieve the purposes of saving labor cost and ensuring good silicon wafer sheet resistance uniformity among batches.
In a first aspect, an embodiment of the present invention provides a flow control method, including:
acquiring the operation sequence of the current diffusion process in the diffusion furnace;
obtaining a small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process and the operation ordinal number of the current diffusion process;
and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
Optionally, the flow control method further includes:
after the liquid diffusion source storage tank is replaced, starting from 0, adding 1 to the number of diffusion process operation times every time the diffusion process is operated;
the method for acquiring the operation ordinal number of the current diffusion process in the diffusion furnace comprises the following steps:
acquiring the total operation times of the diffusion process in a time period from the replacement of the liquid diffusion source storage tank to the current moment;
and adding 1 to the total operation times of the diffusion process to be used as the operation ordinal number of the current diffusion process.
Optionally, before obtaining the small nitrogen flow value required for currently executing the diffusion process according to the corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process, the method further includes:
and constructing the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value.
Optionally, the constructing a corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value includes:
after the liquid diffusion source storage tank is replaced, measuring the sheet resistance of the silicon wafer subjected to each diffusion process;
if the sheet resistance of the silicon wafer after the Mth diffusion process is out of the range of the first set threshold value, determining that the sheet resistance of the silicon wafer drifts after the Mth diffusion process;
correcting a small nitrogen flow value required by the Mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required by the Mth diffusion process;
wherein M is a positive integer.
Optionally, the correcting the small nitrogen flow value required by the mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required by the mth diffusion process includes:
respectively inputting a plurality of small nitrogen with different flow values into the diffusion furnace, and carrying out diffusion process testing;
if the sheet resistance of the silicon wafer subjected to the M1 th diffusion process test is within a second set threshold range, taking the small nitrogen flow value input into the diffusion furnace as the small nitrogen flow value required for executing the M1 th diffusion process when the M1 th diffusion process test is carried out;
wherein M1 is a positive integer.
Optionally, the constructing a corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value further includes:
if two adjacent silicon chip sidesResistance drift occurs at Nth1After the sub-diffusion process and Nth2After the sub-diffusion process;
the small nitrogen flow value B required for performing the nth diffusion processNIs composed of
Wherein, BN2To execute the Nth2Small nitrogen flow value, B, required for the sub-diffusion processN1To execute the Nth1Small nitrogen flow values required for the sub-diffusion process; n, N1And N2Are all positive integers, and N1＜N＜N2。
Optionally, the constructing a corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value further includes:
after the liquid diffusion source storage tank is replaced, if the first silicon wafer sheet resistance drift occurs in the Nth3After the sub-diffusion process;
the small nitrogen flow value B required for performing the N' th diffusion processN’Is composed of
Wherein, BN3To execute the Nth3Small nitrogen flow value, B, required for the sub-diffusion process1Small nitrogen flow values required to perform the 1 st diffusion process; n' and N3Are all positive integers, and 1 is more than N' < N3≤N1。
Optionally, the diffusion source is phosphorus oxychloride or boron tribromide.
In a second aspect, an embodiment of the present invention further provides a flow control device, including:
the operation ordinal number acquisition module is connected with the machine station control module and is used for acquiring the operation ordinal number of the current diffusion process in the diffusion furnace;
the flow determining module is connected with the operation ordinal number obtaining module and is used for obtaining the small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process;
and the machine control module is connected with the flow determination module and used for inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
Optionally, the operation ordinal number obtaining module includes:
the counter is used for starting from the diffusion process running frequency of 0 after the liquid diffusion source storage tank is replaced and adding 1 to the diffusion process running frequency after the diffusion process is run once;
the operation ordinal number acquisition module is specifically configured to:
acquiring the total operation times of the diffusion process in a time period from the replacement of the liquid diffusion source storage tank to the current moment;
and adding 1 to the total operation times of the diffusion process to be used as the operation ordinal number of the current diffusion process.
The flow control method and the flow control device provided by the embodiment of the invention obtain the operation sequence of the current diffusion process in the diffusion furnace; obtaining a small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process; according to the small nitrogen flow value required by the currently executed diffusion process, small nitrogen is input into the diffusion furnace without manual adjustment, and the small nitrogen with the required small nitrogen flow value is input into the diffusion furnace according to the operation sequence of the diffusion process, so that the fluctuation of the square resistance value of the obtained silicon wafer is small, the uniformity of the square resistance of the silicon wafer among batches is good, the automatic production is facilitated, the problems that in the prior art, the small nitrogen with the constant flow is introduced into the diffusion furnace, the square resistance is adjusted by adjusting diffusion or advancing the temperature, the labor cost is increased, but the fluctuation of the square resistance of the obtained silicon wafer is large, and the uniformity of the square resistance of the silicon wafer among batches is poor are solved, and the labor cost is saved under the condition that the uniformity of the square resistance of the silicon wafer.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
FIG. 1 is a schematic diagram of a flow control device of the prior art;
fig. 2 is a flowchart of a flow control method according to an embodiment of the present invention;
fig. 3 is a flowchart of a flow control method according to a second embodiment of the present invention;
fig. 4 is a schematic structural diagram of a flow control device according to a third embodiment of the present invention;
fig. 5 is a diagram illustrating a relationship between operation ordinal numbers and sheet resistances of silicon wafers according to a third embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Fig. 1 is a schematic structural diagram of a flow control device in the prior art. Referring to fig. 1, in the conventional diffusion process, the sheet resistance value of a silicon wafer is adjusted by introducing a fixed small nitrogen flow into a diffusion furnace 1 and adjusting the propulsion time or propulsion temperature. However, the inventor of the present application finds, through research, that the liquid level height of the diffusion source storage tank affects the molar content of the diffusion source carried by the small nitrogen introduced into the diffusion furnace when the small nitrogen flow rate value is the same, so that the molar content of the diffusion source entering the diffusion furnace for diffusion in the prior art changes along with the liquid level height of the diffusion source storage tank, which causes that the sheet resistance value of the silicon wafer obtained after the diffusion process is completed fluctuates greatly in batches, and the sheet resistance value is usually adjusted by subsequently adjusting the propulsion temperature or time, which consumes manpower resources, but the uniformity of the sheet resistance of the obtained silicon wafer is still poor. In order to solve the problem, the embodiment of the invention provides a flow control method and a flow control device so as to obtain silicon sheet square resistance with good batch-to-batch uniformity.
Example one
Fig. 2 is a flowchart of a flow control method according to an embodiment of the present invention. Referring to fig. 2, a flow control method provided in an embodiment of the present invention includes:
s10: and acquiring the operation ordinal number of the current diffusion process in the diffusion furnace.
The current diffusion process refers to a process for diffusing a diffusion source in progress in a diffusion furnace, and the diffusion process in each operation corresponds to an operation ordinal number, namely an operation sequence index. Illustratively, if the nth diffusion process is currently running, the running number of the current diffusion process is N.
S20: and obtaining the small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process.
It should be noted that, when the diffusion source is a liquid diffusion source, in the process of performing the diffusion process, small nitrogen needs to be introduced into the diffusion source, so that the small nitrogen can carry out the diffusion process with the diffusion source having a certain molar content. In order to maintain the mole content of the diffusion source carried in the small nitrogen in a stable range, the flow value of the small nitrogen needs to be adjusted to the flow value of the small nitrogen required by the current diffusion process according to the operation sequence number of the diffusion process.
Factors such as the level of the diffusion source storage tank and the flow rate of the small nitrogen will affect the molar content of the diffusion source carried in the small nitrogen. In the process of each diffusion process operation, small nitrogen input into the diffusion source storage tank can carry out a part of diffusion sources, when the number of times of the diffusion process operation is small, the influence on the sheet resistance of the silicon wafer obtained by the diffusion process at each time is not obvious, but when the number of times of the diffusion process operation is too large, the liquid level height of the diffusion source storage tank can be changed along with the small nitrogen input, so that the sheet resistance value of the silicon wafer is influenced, and the sheet resistance fluctuation obtained by adjusting the flow value of the small nitrogen according to the liquid level height of the diffusion source storage tank is large. When the sheet resistance difference value of the silicon wafer is large, the window of a subsequent sintering process can be greatly reduced, and when the sheet resistance difference value of the silicon wafer is too large, the silicon wafer can be reworked, so that materials and cost are wasted.
Therefore, in order to ensure the uniformity of sheet resistance of the silicon wafers obtained in the diffusion process batches, expand a sintering process window and reduce material waste and rework cost, the small nitrogen flow value is adjusted to the small nitrogen flow value corresponding to the operation process sequence number when the diffusion process is operated every time, so that the mole content of the diffusion source carried by the small nitrogen input into the diffusion furnace in the diffusion process is basically unchanged every time.
Commonly used diffusion sources may be compounds of boron, phosphorus, antimony or arsenic, and when the diffusion source is a liquid diffusion source, the diffusion source may alternatively be phosphorus oxychloride or boron tribromide.
S30: and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
It can be understood that the small nitrogen is input into the diffusion source before being input into the diffusion furnace to carry the diffusion source out for participating in the diffusion reaction, so the small nitrogen flow value corresponding to the operation order of the diffusion process can be the small nitrogen flow value directly input into the diffusion furnace, or the small nitrogen flow value input into the diffusion source before being input into the diffusion furnace. When the flow value of the small nitrogen input into the diffusion source after passing through the diffusion source does not change much, the small nitrogen flow value input into the diffusion source and the small nitrogen flow value input into the diffusion furnace can be regarded as the same small nitrogen flow value.
The flow control method provided by the embodiment of the invention obtains the operation ordinal number of the current diffusion process in the diffusion furnace; obtaining the small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process; and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process. According to the embodiment of the invention, manual adjustment is not needed, the automatic production is facilitated, the small nitrogen with the required small nitrogen flow value is input into the diffusion furnace according to the operation sequence of the diffusion process, the molar content of a diffusion source carried in the small nitrogen in each diffusion process is basically unchanged, the fluctuation of the sheet resistance value of the obtained silicon wafer is smaller, the uniformity of the sheet resistance among batches is good, the problems that in the prior art, the small nitrogen with the constant flow is introduced into the diffusion furnace, the sheet resistance is adjusted by adjusting diffusion or pushing temperature, the labor cost is increased, but the fluctuation of the sheet resistance of the obtained silicon wafer is large, and the uniformity of the sheet resistance among batches is poor are solved, and the purposes of saving the labor cost and good uniformity of the sheet resistance among batches are realized.
Because the number of process operations in the diffusion furnace is not limited, the process operation number of the diffusion furnace is continuously increased, and in order to avoid problems such as error of the operation number caused by an excessively large operation number of the diffusion process, for example, on the basis of the above scheme, the flow control method may further include: and after the liquid diffusion source storage tank is replaced, starting from 0, and adding 1 to the number of diffusion process operation times every time the diffusion process is operated.
Because the times of the diffusion processes which can be carried out by one liquid diffusion source storage tank are basically the same, the operation ordinal number of the diffusion processes is a finite value and is not always subjected to infinite superposition, the probability of error of recording the operation process times can be reduced, and the accuracy of the operation times of the diffusion processes is ensured.
Then S10: obtaining the operation ordinal number of the current diffusion process in the diffusion furnace may include:
first, the total running times of the diffusion process in the time period from the replacement of the liquid diffusion source storage tank to the current time is obtained.
And secondly, adding 1 to the total operation times of the diffusion process to be used as the operation times of the current diffusion process.
It can be understood that the method for obtaining the operation ordinal number of the current diffusion process is not particularly limited, and the accurate operation ordinal number of the current diffusion process may also be obtained in other manners.
Example two
The present embodiment is a specific example of the first embodiment. Fig. 3 is a flowchart of a flow control method according to a second embodiment of the present invention. Illustratively, referring to fig. 3, on the basis of the foregoing embodiment, the flow control method may include:
s10: and acquiring the operation ordinal number of the current diffusion process in the diffusion furnace.
S21: and constructing the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value.
There are various specific implementation methods of this step, and the following description will be made in detail with reference to typical examples, but the present application is not limited thereto.
Firstly, after a liquid diffusion source storage tank is replaced, the sheet resistance of the silicon wafer after each diffusion process is measured.
The silicon sheet square resistance is the average square resistance of a plurality of silicon sheet square resistances obtained by each diffusion process. Because the factors such as the temperature of each area in the diffusion furnace are not completely the same, the sheet resistance of the obtained silicon wafer also has a certain difference after the same complete process operation in the diffusion furnace is finished. In order to determine the sheet resistance value of the same batch of silicon wafers, the silicon wafers in different areas can be taken, the corresponding sheet resistance is obtained through measurement, and the average value of the sheet resistances of the silicon wafers is defined as the sheet resistance of the silicon wafer obtained after the diffusion process is completed.
And secondly, if the sheet resistance of the silicon wafer after the Mth diffusion process is out of the range of the first set threshold value, determining that the sheet resistance of the silicon wafer after the Mth diffusion process drifts, wherein M is a positive integer.
For example, a target square resistance value that is the best predicted square resistance value may be set. A first set threshold range may also be set, and the first set threshold range may be set according to actual needs, and the first set threshold range may be a fluctuation range of the sheet resistance acceptable near the target sheet resistance, for example, the first set threshold range may be a sheet resistance range with a target sheet resistance value floating up and down by 10%.
And measuring the sheet resistance value of the silicon wafer after each diffusion process, and when the sheet resistance value of the silicon wafer is within a first set threshold range, indicating that the sheet resistance of the silicon wafer is the predicted sheet resistance of the silicon wafer, the sheet resistance does not drift, the silicon wafer is qualified, and the obtained silicon wafer can be continuously processed by the subsequent process without being reworked. When the sheet resistance does not drift, the small nitrogen flow value input by the sub-diffusion process can be determined as the small nitrogen flow value corresponding to the operation ordinal number of the sub-diffusion process.
When the sheet resistance of the silicon wafer is out of the range of the first set threshold value, the sheet resistance of the silicon wafer obtained after the diffusion process is shown to drift and deviate from the acceptable sheet resistance range, namely the silicon wafer is unqualified, and the silicon wafer obtained by the diffusion process cannot participate in the subsequent process processing.
And finally, correcting the small nitrogen flow value required by the Mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required by the Mth diffusion process.
When the sheet resistance of the silicon wafer drifts after the mth diffusion process, it is shown that the molar content of the diffusion source carried in the input small nitrogen may be changed after the mth diffusion process. Therefore, the flow rate of the small nitrogen required by the mth diffusion process needs to be adjusted to make the sheet resistance of the small nitrogen return to the first set threshold range, and the flow rate of the small nitrogen which can make the sheet resistance return to the first set threshold range is taken as the flow rate of the small nitrogen required for performing the mth diffusion process.
And when the sheet resistance drifts every time, determining the operation ordinal number of the diffusion process when the sheet resistance drifts, correcting the small nitrogen flow value required by the operation ordinal number of the diffusion process corresponding to the operation ordinal number of the diffusion process, inputting the corrected small nitrogen flow value into the diffusion process after the diffusion process when the sheet resistance drifts until the next sheet resistance drifts, and correcting the small nitrogen flow value again.
And determining the small nitrogen flow values corresponding to the operation ordinal numbers of all the diffusion processes, so as to obtain the corresponding relation between the operation ordinal number of each diffusion process and the small nitrogen flow value corresponding to the operation ordinal number.
S20: obtaining a small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process and the operation ordinal number of the current diffusion process;
s30: and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
According to the flow control method provided by the embodiment of the invention, the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process is constructed in advance, the small nitrogen flow value required for currently executing the diffusion process is input into the diffusion furnace according to the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process and the operation ordinal number of the current diffusion process, only the small nitrogen flow value is adjusted, the molar contents of diffusion sources entering the diffusion furnace in batches are basically the same, manual intervention on the subsequent process is not needed, the variation factor of diffusion conditions is reduced, and the uniformity of the sheet resistance of the obtained silicon wafers in batches is good.
In the above-described embodiments, there are many methods for correcting the required small nitrogen flow value, and a typical example will be described in detail below, but the present application is not limited thereto. For example, on the basis of the above technical solution, modifying the small nitrogen flow value required by the mth diffusion process, and taking the modified small nitrogen flow value as the small nitrogen flow value required by the mth diffusion process, may include:
firstly, small nitrogen with a plurality of different flow values is respectively input into a diffusion furnace for diffusion process testing.
When the Mth diffusion process is operated, the sheet resistance can drift due to the input small nitrogen flow value, small nitrogen with different flow values is respectively input into the diffusion furnace, the sheet resistance of the silicon wafer after the diffusion process corresponding to each small nitrogen flow value is completed is measured, and the sheet resistance of the silicon wafer at different small nitrogen flow values in the Mth diffusion process is determined. And in order to avoid overlarge error range, multiple tests can be carried out on each small nitrogen flow value in the Mth diffusion process, and the silicon sheet square resistance correspondingly obtained by each small nitrogen flow value in the Mth diffusion process is determined through an average or other calculation modes.
Secondly, if the sheet resistance of the silicon wafer subjected to the M1 th diffusion process test is within a second set threshold range, the small nitrogen flow value input into the diffusion furnace when the M1 th diffusion process test is performed is taken as the small nitrogen flow value required for executing the M < th > diffusion process, wherein M1 is a positive integer.
For example, a second set threshold range may be set, which is also an acceptable range of variance of the sheet resistance, and may be the same as or different from the first set threshold range. For example, in order to obtain an azimuthally resistance closer to the target azimuthally resistance value after the modified small nitrogen flow value is subjected to the diffusion process, the second set threshold range may be set smaller than the first set threshold range, for example, when the first set threshold range is set to be an azimuthally resistance range in which the target azimuthally resistance value is 10% vertically shifted, the second set threshold range may be set to be an azimuthally resistance range in which the target azimuthally resistance value is 5% vertically shifted. Optionally, the second set threshold range may be set to be smaller, for example, the second set threshold range is set as a target sheet resistance value, that is, the sheet resistance obtained after the modified small nitrogen flow value is subjected to the diffusion process is the set target sheet resistance.
When the mth diffusion process is operated, the sheet resistance is shifted due to the input small nitrogen flow value, small nitrogen with different flow values is respectively input into the diffusion furnace every time the mth diffusion process is operated, and illustratively, the operation numbers of the diffusion processes with different small nitrogen flow values input in the mth diffusion process are respectively marked as Mx, My, M1, … and Mn. When the small nitrogen of the small nitrogen flow value inputted at the M1 time can obtain the sheet resistance within the second set threshold range, the small nitrogen flow value inputted at the M1 time diffusion process inputted at the small nitrogen flow value is used as the small nitrogen flow value required for executing the M diffusion process.
In the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value constructed according to the method, the small nitrogen flow value is only required to be corrected for the diffusion process in which the sheet resistance drifts each time, and the small nitrogen flow value corresponding to the diffusion process in which the sheet resistance does not drift is not corrected. However, in the diffusion process with adjacent running numbers, the difference between the mole contents of the diffusion sources carried by small nitrogen with the same flow value is small and can be ignored easily. The molar content difference of the small nitrogen carried diffusion sources with the same flow value is accumulated along with the increase of the operation times of the diffusion process, and when the molar content difference of the small nitrogen carried diffusion sources reaches a certain value, the sheet resistance of the silicon wafer subjected to the diffusion process can drift. That is, in the diffusion process without drift of the sheet resistance, the flow value of the small nitrogen is not modified, and although the sheet resistance does not drift, the mole content of the diffusion source carried by the input small nitrogen is slightly changed.
In order to maintain the mole content of the diffusion source carried in the small nitrogen input into the diffusion furnace in each diffusion process within a stable range, the embodiment of the invention also provides another method for constructing the corresponding relation between the operation ordinal number of the diffusion process and the flow value of the small nitrogen. Specifically, on the basis of the foregoing embodiment, S21 may further include:
if the sheet resistance drift of two adjacent silicon chips occurs in the Nth1After the sub-diffusion process and Nth2After the sub-diffusion process, the small nitrogen flow value B required by the N-th diffusion process is executedNIs composed of
Wherein, BN2To execute the Nth2Small nitrogen flow value, B, required for the sub-diffusion processN1To execute the Nth1Small nitrogen flow values required for the sub-diffusion process; n, N1And N2Are all positive integers, and N1＜N＜N2。
It should be noted that, because the difference between the sheet resistance values obtained after two adjacent diffusion processes is small, it is not easy to determine the correction value of the small nitrogen flow value corresponding to each diffusion process. Therefore, the small nitrogen flow value required by each diffusion process between the two diffusion processes can be corrected through the small nitrogen flow value required by the two diffusion processes with larger sheet resistance difference. By diffusion process during two adjacent sheet resistance drifts (Nth)1Second and Nth2Next) the respective required small nitrogen flow values: b isN1And BN2The correction value of the small nitrogen flow value required between the two diffusion processes can be determined, and the correction value of the small nitrogen flow value required in each diffusion process can be determined according to the correction value and the difference value of the operation ordinal number of the two diffusion processes, so that the required small nitrogen flow value corresponding to the operation ordinal number of each diffusion process can be determined according to the formula (1).
In which the diffusion process is performed twice during the drift of the adjacent sheet resistance (the firstN1Second and Nth2Next) the respective required small nitrogen flow values: b isN1And BN2The specific determination method is not limited at all. The following is a detailed description of exemplary examples, but is not intended to limit the scope of the disclosure. Exemplarily, if N1The sheet resistance of the silicon chip drifts after the sub-diffusion process, and can be in the Nth1Inputting modified B in +1 diffusion processN1+1Calculating the sheet resistance obtained after the diffusion process according to the small nitrogen flow value; at the Nth1Inputting modified B in +2 diffusion processesN1+2Calculating the sheet resistance obtained after the diffusion process according to the small nitrogen flow value; go back and forth until the Nth1Inputting modified B in + n times diffusion processN1+nThe obtained sheet resistance is the set target sheet resistance, then the Nth sheet resistance can be determined1The small nitrogen flow value required by the + n times diffusion process is BN1+nThe Nth can be determined according to equation (1)1Sub-diffusion process and Nth1And between + n times of diffusion processes, the required small nitrogen flow value corresponding to the operation sequence of each diffusion process. It is understood that N, N1And N2Are all positive integers, i.e. N1It may be 1, that is, even if the sheet resistance drifts after the 1 st diffusion process, the required small nitrogen flow value corresponding to the subsequent diffusion process operation number may be determined according to the formula (1).
When the sheet resistance drift occurs for the first time, the small nitrogen flow value required by the diffusion process before the sheet resistance drift occurs needs to be corrected on the basis of the small nitrogen flow value required by the 1 st diffusion process. Accordingly, S21 may further include:
after the liquid diffusion source storage tank is replaced, if the first silicon wafer sheet resistance drift occurs in the Nth3After the sub-diffusion process, the small nitrogen flow value B required for the N' th sub-diffusion process is performedN’Is composed of
Wherein, BN3To execute the Nth3Small nitrogen flow required for sub-diffusion processMagnitude, B1Small nitrogen flow values required to perform the 1 st diffusion process; n' and N3Are all positive integers, and 1 is more than N' < N3≤N1。
It can be understood that after the liquid diffusion source storage tank is replaced, when the sheet resistance of the silicon wafer drifts for the first time, the diffusion process in which the sheet resistance drifts for the previous time does not exist, and the small nitrogen flow value required by each diffusion process before the sheet resistance of the silicon wafer drifts needs to be corrected on the basis of the small nitrogen flow value required by the diffusion process for the 1 st time. Wherein, the N3After the sub-diffusion process, a first silicon sheet resistance drift occurs, illustratively, the Nth3The sub-diffusion process can be one of the diffusion processes in the two adjacent sheet resistance drifts in the technical scheme, namely N3＝N1(ii) a Or the Nth diffusion process in the two adjacent sheet resistance drifts in the technical scheme1Diffusion processes preceding the sub-diffusion process, i.e. N3＜N1。
Namely, determining a required small nitrogen flow value corresponding to each diffusion process operation ordinal number before the diffusion process operation ordinal number occurring in the first sheet resistance drift through a formula (2); and (2) determining the required small nitrogen flow value corresponding to each diffusion process operation ordinal number between the diffusion process operation ordinal numbers when the sheet resistance drifts twice through a formula (1), so as to determine the required small nitrogen flow value corresponding to each diffusion process operation ordinal number during the period from the replacement of the liquid diffusion source storage tank to the next replacement.
The small nitrogen flow value correction is carried out on each diffusion process after the liquid diffusion source storage tank is replaced, the corrected flow value is more accurate, the diffusion source carried by the small nitrogen input at each time can be basically maintained in a stable range, the uniformity of the sheet square resistance of the silicon wafers obtained in batches can be better, when the molar content of the diffusion source input into the diffusion furnace is stable, the sheet square resistance can be adjusted without manually adjusting the push time, and the labor cost is saved.
EXAMPLE III
Fig. 4 is a schematic structural diagram of a flow control device according to a third embodiment of the present invention. Referring to fig. 4, a flow control device provided in the third embodiment of the present invention includes: the operation ordinal number acquisition module 2 is connected with the machine control module 4 and is used for acquiring the operation ordinal number of the current diffusion process in the diffusion furnace 1; the flow determining module 3 is connected with the operation ordinal number obtaining module 2 and is used for obtaining the small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process; and the machine control module 4 is connected with the flow determination module 3 and is used for inputting small nitrogen to the diffusion furnace 1 according to the small nitrogen flow value required by the currently executed diffusion process.
The specific manner of acquiring the operation ordinal number of the diffusion process by the operation ordinal number acquisition module 2 is not limited, and for example, the operation number of the diffusion process in the diffusion furnace 1 may be recorded by the machine control module 4, and the operation ordinal number acquisition module 2 acquires the operation ordinal number of the current diffusion process from the machine control module 4.
The corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value can be constructed in advance, for example, before the diffusion process is operated, the corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value is determined, the flow determination module 3 can determine the small nitrogen flow value required by the current diffusion process according to the corresponding relationship and the operation ordinal number of the current diffusion process, and the small nitrogen with the small nitrogen flow value required by the current diffusion process is input into the diffusion furnace 1 through the control of the machine control module 4, so that the time is saved.
It should be noted that, when the diffusion source is a liquid diffusion source, the small nitrogen is introduced into the diffusion source before being input into the diffusion furnace 1, so that the small nitrogen carries a certain molar content of the diffusion source from the diffusion source into the diffusion furnace 1 to participate in the diffusion reaction.
Optionally, the small nitrogen flow input into the diffusion furnace may be controlled by the machine control module 4 by controlling the mass flow controller, or may be controlled by other flow control devices.
According to the flow control device provided by the embodiment of the invention, the operation sequence of the current diffusion process in the diffusion furnace is obtained through the operation sequence obtaining module; the flow determination module determines the small nitrogen flow value required by the currently executed diffusion process according to the corresponding relation between the constructed operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the currently executed diffusion process; the machine table control module inputs small nitrogen to the diffusion furnace according to the small nitrogen flow value required by the current executing diffusion process, manual adjustment is not needed, automatic production is facilitated, the small nitrogen with the small nitrogen flow value required by the current executing diffusion process is input to the diffusion furnace according to the operation sequence of the diffusion process, so that the fluctuation of the sheet resistance value of the obtained silicon wafer is small, the uniformity of the sheet resistance among batches is good, the problems that in the prior art, the small nitrogen with the constant flow is introduced into the diffusion furnace, the sheet resistance is adjusted by adjusting diffusion or advancing the temperature, the labor cost is increased, but the fluctuation of the sheet resistance of the obtained silicon wafer is large, and the uniformity of the sheet resistance among batches is poor are solved, and the purposes of saving the labor cost and good uniformity of the sheet resistance among.
Optionally, the operation ordinal number obtaining module 1 may include: the counter 11 is used for starting from the diffusion process running frequency of 0 after the liquid diffusion source storage tank is replaced, and adding 1 to the diffusion process running frequency every time the diffusion process is run; the operation ordinal number obtaining module 2 is specifically configured to: acquiring the total operation times of the diffusion process in a time period from the replacement of the liquid diffusion source storage tank to the current moment; and adding 1 to the total operation times of the diffusion process to be used as the operation ordinal number of the current diffusion process.
The counter 11 can record the running times of the diffusion process in the diffusion furnace 1, and after the liquid diffusion source storage tank is replaced each time, the running times of the diffusion process are started from 0, so that more accurate running times of the process can be obtained, errors in the process of accumulating the running times by overlapping for many times for a long time are avoided, the corresponding running times of the process can be reduced in the process of corresponding relation between the running number of the framework diffusion process and the small nitrogen flow value, human resources are saved, and material loss is reduced.
The operation ordinal number obtaining module 2 is used for obtaining the operation ordinal number of the diffusion process currently operated, so that the small nitrogen flow value required by the operation ordinal number of the current diffusion process can be determined, the small nitrogen carried by the small nitrogen which is introduced into the diffusion furnace 1 every time is ensured to be maintained in a stable range, and the silicon sheet resistance with good batch-to-batch uniformity is obtained.
Fig. 5 is a diagram illustrating a relationship between operation ordinal numbers and sheet resistances of silicon wafers according to a third embodiment of the present invention. In fig. 5, the abscissa represents the operation ordinal number of the diffusion process, the ordinate represents the square resistance of the silicon wafer after the diffusion process is operated, a represents the relationship between the operation ordinal number and the square resistance of the silicon wafer obtained by using the flow rate control device provided in the embodiment of the present invention, b represents the relationship between the operation ordinal number and the square resistance of the silicon wafer obtained by using the conventional flow rate control device (i.e., the flow rate control device provided in fig. 1), and c represents the set target square resistance.
As can be seen from fig. 5, compared with the conventional flow control device, the flow control device obtained by the technical scheme in the embodiment of the present invention has smaller sheet resistance fluctuation and better batch-to-batch uniformity than the comparative example.
Illustratively, a target square resistance value may be set, and a first predetermined threshold range, for example, 90 Ω/□, may be set, with the first predetermined threshold range being 5% of the target square resistance, i.e., 85.5 Ω/□ -94.5 Ω/□. As can be seen from fig. 5, the silicon wafer sheet resistance difference obtained by the technical scheme provided by the embodiment of the present invention is small, and the uniformity among batches is good.
Therefore, the flow control method and the flow control device provided by the embodiment of the invention do not need manual adjustment, are favorable for automatic production, and input small nitrogen with a required small nitrogen flow value into the diffusion furnace according to the operation sequence of the diffusion process, so that the fluctuation of the sheet resistance value of the obtained silicon wafer is small, the uniformity of the sheet resistance among batches is good, the problems that in the prior art, the small nitrogen with a constant flow is introduced into the diffusion furnace, the sheet resistance is adjusted by adjusting the propelling temperature, the labor cost is increased, but the fluctuation of the sheet resistance of the obtained silicon wafer is large, and the uniformity of the sheet resistance among batches is poor are solved, and the purposes of saving the labor cost and achieving good uniformity of the sheet resistance among batches are achieved.
The product can execute the method provided by any embodiment of the invention, and has corresponding functional modules and beneficial effects of the execution method.
Example four
The present embodiment may provide an optional specific example based on the second embodiment.
Illustratively, on the basis of the above embodiment, the flow control method may include:
s10: and acquiring the operation ordinal number of the current diffusion process in the diffusion furnace.
S21: and constructing the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value.
Wherein, S21 may include:
after the liquid diffusion source storage tank is replaced, if the first silicon wafer sheet resistance drift occurs in the Nth3After the sub-diffusion process, the small nitrogen flow value B required for the N' th sub-diffusion process is performedN’Is composed of
Wherein, BN3To execute the Nth3Small nitrogen flow value, B, required for the sub-diffusion process1Small nitrogen flow values required to perform the 1 st diffusion process; n' and N3Are all positive integers, and 1 is more than N' < N3≤N1。
If the sheet resistance drift of two adjacent silicon chips occurs in the Nth1After the sub-diffusion process and Nth2After the sub-diffusion process, the small nitrogen flow value B required by the N-th diffusion process is executedNIs composed of
Wherein, BN2To execute the Nth2Small nitrogen flow value, B, required for the sub-diffusion processN1To execute the Nth1Small nitrogen flow values required for the sub-diffusion process; n, N1And N2Are all positive integers, and N1＜N＜N2。
It can be understood that after the liquid diffusion source storage tank is replaced and the 1 st diffusion process is performed, the sheet resistance does not drift, and the drift of the sheet resistance of the first silicon wafer occurs in the Nth3Sub-diffusion processThen (1 < N)3). May be in the Nth3Setting a plurality of different small nitrogen flow values for diffusion during the sub-diffusion process, detecting the sheet resistance of the silicon wafer after the diffusion process is finished under each small nitrogen flow value, and assuming that the small nitrogen flow value capable of obtaining the target sheet resistance is found to be B after detectionN3Then N is3The sub-diffusion process is corrected to obtain the required small nitrogen flow value B of the target sheet resistanceN3Then can pass through the formula
Determination of the 1 st diffusion Process and the Nth3Small nitrogen flow value B required for N' th sub-diffusion process between sub-diffusion processesN’。
When N is present3＝N1When, the N-th2After the sub-diffusion process, the second generation of sheet resistance drift passes
To determine the Nth1Sub-diffusion process and Nth2Small nitrogen flow value B required for Nth diffusion process between sub-diffusion processesN. And when the sheet resistance drift occurs again, repeating the mode of determining the required small nitrogen flow value when the sheet resistance of the adjacent two silicon wafers drifts. Therefore, the required small nitrogen flow value corresponding to each diffusion process in the whole liquid diffusion source storage tank can be determined until the liquid diffusion source storage tank is replaced again.
S20: obtaining a small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process and the operation ordinal number of the current diffusion process;
s30: and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
According to the embodiment of the invention, manual adjustment is not needed, the automatic production is facilitated, the small nitrogen with the required small nitrogen flow value is input into the diffusion furnace according to the operation sequence of the diffusion process, the molar content of a diffusion source carried in the small nitrogen in each diffusion process is basically unchanged, the fluctuation of the sheet resistance value of the obtained silicon wafer is smaller, the uniformity of the sheet resistance among batches is good, the problems that in the prior art, the small nitrogen with the constant flow is introduced into the diffusion furnace, the sheet resistance is adjusted by adjusting diffusion or pushing temperature, the labor cost is increased, but the fluctuation of the sheet resistance of the obtained silicon wafer is large, and the uniformity of the sheet resistance among batches is poor are solved, and the purposes of saving the labor cost and good uniformity of the sheet resistance among batches are realized.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
Claims (8)
1. A method of flow control, comprising:
acquiring the operation sequence of the current diffusion process in the diffusion furnace;
obtaining a small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number and the small nitrogen flow value of the diffusion process and the operation ordinal number of the current diffusion process;
before obtaining the small nitrogen flow value required by the current execution of the diffusion process according to the corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process, the method further comprises the following steps:
constructing a corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value;
wherein, the corresponding relation of the operation ordinal number and the small nitrogen flow value of the diffusion process is constructed, and the method comprises the following steps:
after the liquid diffusion source storage tank is replaced, measuring the sheet resistance of the silicon wafer subjected to each diffusion process;
if the sheet resistance of the silicon wafer after the Mth diffusion process is out of the range of the first set threshold value, determining that the sheet resistance of the silicon wafer drifts after the Mth diffusion process;
correcting a small nitrogen flow value required by the Mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required by the Mth diffusion process;
wherein M is a positive integer;
and inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
2. The flow control method according to claim 1, characterized by further comprising:
after the liquid diffusion source storage tank is replaced, starting from 0, adding 1 to the number of diffusion process operation times every time the diffusion process is operated;
the method for acquiring the operation ordinal number of the current diffusion process in the diffusion furnace comprises the following steps:
acquiring the total operation times of the diffusion process in a time period from the replacement of the liquid diffusion source storage tank to the current moment;
and adding 1 to the total operation times of the diffusion process to be used as the operation ordinal number of the current diffusion process.
3. The flow control method according to claim 1, wherein the correcting the small nitrogen flow value required by the mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required for performing the mth diffusion process, comprises:
respectively inputting a plurality of small nitrogen with different flow values into the diffusion furnace, and carrying out diffusion process testing;
if the sheet resistance of the silicon wafer subjected to the M1 th diffusion process test is within a second set threshold range, taking the small nitrogen flow value input into the diffusion furnace as the small nitrogen flow value required for executing the M1 th diffusion process when the M1 th diffusion process test is carried out;
wherein M1 is a positive integer.
4. The flow control method according to claim 1, wherein the establishing of the correspondence between the operation ordinal number of the diffusion process and the small nitrogen flow value further comprises:
if the sheet resistance drift of two adjacent silicon chips occurs in the Nth1After the sub-diffusion process and Nth2After the sub-diffusion process;
the small nitrogen flow value B required for performing the nth diffusion processNIs composed of
Wherein, BN2To execute the Nth2Small nitrogen flow value, B, required for the sub-diffusion processN1To execute the Nth1Small nitrogen flow values required for the sub-diffusion process; n, N1And N2Are all positive integers, and N1＜N＜N2。
5. The flow control method according to claim 4, wherein the establishing of the correspondence between the operation ordinal number of the diffusion process and the small nitrogen flow value further comprises:
after the liquid diffusion source storage tank is replaced, if the first silicon wafer sheet resistance drift occurs in the Nth3After the sub-diffusion process;
the small nitrogen flow value B required for performing the N' th diffusion processN’Is composed of
Wherein, BN3To execute the Nth3Small nitrogen flow value, B, required for the sub-diffusion process1Small nitrogen flow values required to perform the 1 st diffusion process; n' and N3Are all positive integers, and 1 is more than N' < N3≤N1。
6. The flow control method according to claim 2,
the diffusion source is phosphorus oxychloride or boron tribromide.
7. A flow control device, comprising:
the operation ordinal number acquisition module is connected with the machine station control module and is used for acquiring the operation ordinal number of the current diffusion process in the diffusion furnace;
the flow determining module is connected with the operation ordinal number obtaining module and is used for obtaining the small nitrogen flow value required by the current diffusion process according to the corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the current diffusion process;
before obtaining the small nitrogen flow value required by the currently executed diffusion process according to the corresponding relationship between the operation ordinal number of the diffusion process and the small nitrogen flow value and the operation ordinal number of the currently executed diffusion process, the method further comprises the following steps: constructing a corresponding relation between the operation ordinal number of the diffusion process and the small nitrogen flow value; wherein, the corresponding relation of the operation ordinal number and the small nitrogen flow value of the diffusion process is constructed, and the method comprises the following steps:
after the liquid diffusion source storage tank is replaced, measuring the sheet resistance of the silicon wafer subjected to each diffusion process;
if the sheet resistance of the silicon wafer after the Mth diffusion process is out of the range of the first set threshold value, determining that the sheet resistance of the silicon wafer drifts after the Mth diffusion process;
correcting a small nitrogen flow value required by the Mth diffusion process, and taking the corrected small nitrogen flow value as the small nitrogen flow value required by the Mth diffusion process;
wherein M is a positive integer;
and the machine control module is connected with the flow determination module and used for inputting small nitrogen into the diffusion furnace according to the small nitrogen flow value required by the currently executed diffusion process.
8. The flow control device of claim 7, wherein the run number acquisition module comprises:
the counter is used for starting from the diffusion process running frequency of 0 after the liquid diffusion source storage tank is replaced and adding 1 to the diffusion process running frequency after the diffusion process is run once;
the operation ordinal number acquisition module is specifically configured to:
acquiring the total operation times of the diffusion process in a time period from the replacement of the liquid diffusion source storage tank to the current moment;
and adding 1 to the total operation times of the diffusion process to be used as the operation ordinal number of the current diffusion process.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101237010A (en) * | 2008-02-29 | 2008-08-06 | 珈伟太阳能(武汉)有限公司 | Method for improving solar battery diffusion |
| CN102254991A (en) * | 2011-06-30 | 2011-11-23 | 浚鑫科技股份有限公司 | Crystalline silicon solar cell and diffusion method thereof |
| CN102569523A (en) * | 2012-02-09 | 2012-07-11 | 苏州盛康光伏科技有限公司 | Diffusion method for polycrystalline silicon solar photovoltaic cell silicon chip |
| CN104393107A (en) * | 2014-10-27 | 2015-03-04 | 中国电子科技集团公司第四十八研究所 | High-sheet resistance crystalline silicon cell low-voltage diffusion process |
| CN105428226A (en) * | 2015-10-29 | 2016-03-23 | 晋能清洁能源科技有限公司 | Tubular POCl3 diffusion sheet resistance automatic adjusting method |
| CN206022326U (en) * | 2016-08-31 | 2017-03-15 | 无锡尚德太阳能电力有限公司 | The intelligence control system of adjustment diffused sheet resistance |
-
2017
- 2017-12-28 CN CN201711456622.5A patent/CN108198771B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101237010A (en) * | 2008-02-29 | 2008-08-06 | 珈伟太阳能(武汉)有限公司 | Method for improving solar battery diffusion |
| CN102254991A (en) * | 2011-06-30 | 2011-11-23 | 浚鑫科技股份有限公司 | Crystalline silicon solar cell and diffusion method thereof |
| CN102569523A (en) * | 2012-02-09 | 2012-07-11 | 苏州盛康光伏科技有限公司 | Diffusion method for polycrystalline silicon solar photovoltaic cell silicon chip |
| CN104393107A (en) * | 2014-10-27 | 2015-03-04 | 中国电子科技集团公司第四十八研究所 | High-sheet resistance crystalline silicon cell low-voltage diffusion process |
| CN105428226A (en) * | 2015-10-29 | 2016-03-23 | 晋能清洁能源科技有限公司 | Tubular POCl3 diffusion sheet resistance automatic adjusting method |
| CN206022326U (en) * | 2016-08-31 | 2017-03-15 | 无锡尚德太阳能电力有限公司 | The intelligence control system of adjustment diffused sheet resistance |
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