CN116759346B - Quick temperature control slide holder, photoresist removing etching equipment and photoresist removing process - Google Patents

Abstract

The invention provides a rapid temperature-controlled film carrier, degumming and etching equipment, and a degumming process. The rapid temperature-controlled film carrier includes a base. A cooling circuit is distributed in the base, and the cooling circuit is provided with an inlet and an outlet. ; Heating layer, arranged on the base; electric heating wire, arranged in the heating layer; interlayer, arranged between the base and the heating layer, used to physically isolate the electric heating wire and the cooling circuit; the interlayer is a good conductor of heat; Temperature sensor, the sensing part of the temperature sensor passes through the interlayer and contacts the heating layer. The invention can control the temperature of the carrier stage to drop slightly during the wafer degumming process through the calibrated flow rate of process coolant, offset the rising trend of the etching rate caused by the rise in the wafer surface temperature during the degumming process, and control the degumming process. The speed basically achieves a uniform effect; on the premise of ensuring complete glue removal, the remaining time after glue removal is more accurately controlled to minimize the oxidation degree of the easily oxidized film layer.

Description

Rapid temperature control slide stage, glue removal etching equipment and glue removal process

Technical field

The invention relates to the technical field of semiconductor equipment, in particular to a rapid temperature control slide stage, glue removal etching equipment and glue removal process.

Background technique

In the etching equipment, the existing slide stage is shown in Figure 1, including a base 1. A heating layer 2 is provided on the base 1. Electric heating wires 3 are distributed in the heating layer 2. The electric heating wires 3 are usually arranged in a spiral. Or reciprocating; the heating layer 2 is also provided with a temperature sensor 4, such as a thermocouple, which can monitor the temperature of the heating layer 2 in real time; the wafer to be processed is placed on the heating layer 2.

The glue involved in the wafer degluing process is usually hydrocarbons. The degluing process mainly involves the introduction of O2 under microwave or ion source bombardment to carry out the combustion reaction of C+O and H+O. During the process , will continuously generate heat; and the etching rate of the glue has a strong correlation with temperature. The heat generated during the process will partially accumulate on the surface of the wafer, thus having a direct impact and accelerating the etching rate of the glue. The existing wafer carrier is controlled at a constant temperature during the glue removal process. For example, the process temperature is set to 200°C. During the glue removal process, as the heat continues to be generated on the wafer surface, the glue removal rate continues to accelerate with the process; This will make it difficult to control the time required for the entire glue removal process.

For example, the degumming time of a certain kind of glue at a constant temperature of 200°C is estimated to be 120s. However, due to the accelerated degumming rate, the actual degluing time is only 100s or less, and the remaining time after complete degumming is 20s or longer; for some easily The oxidized process film will easily form an oxide film on the surface after the glue is completely removed; taking metal Al as an example, Al will react with O2: 4Al+3O2=2Al2O3. Al is used as a conductor in the wafer structure, and Al2O3 has very poor electrical conductivity and is basically non-conductive at room temperature, which will affect some of the performance of the product.

Contents of the invention

In order to solve at least one technical problem in the prior art, embodiments of the present invention provide a fast temperature-controlled slide stage, degumming etching equipment and a degumming process to control the degumming rate to basically achieve a uniform effect, which facilitates better Control the remaining time after glue removal to minimize the oxidation degree of the easily oxidized film. In order to achieve the above technical objectives, the technical solutions adopted in the embodiments of the present invention are:

In a first aspect, embodiments of the present invention provide a rapid temperature control slide stage, including:

A base with a cooling circuit distributed in the base, and the cooling circuit is provided with an inlet and an outlet;

The heating layer is arranged on the base;

Electric heating wire is arranged in the heating layer;

An interlayer is provided between the base and the heating layer for physically isolating the heating wire and the cooling circuit; the interlayer is a good conductor of heat;

Temperature sensor, the sensing part of the temperature sensor passes through the interlayer and contacts the heating layer;

The cooling loop is used to pass in process coolant during the degumming process; the flow rate of the process coolant needs to be calibrated in advance. When calibrating the process coolant flow rate, it includes:

When the wafer degumming process starts, set a preset time, which is less than the predetermined degluing time, but greater than 90% of the predetermined degluing time; pass an initial flow of process coolant into the cooling loop, and after the preset Lower the temperature of the heating layer from the first degumming process temperature to the second degumming process temperature within a certain period of time;

Measure the etching rate of the glue strip in at least three periods within the preset time period; compare the etching rates in each period;

If the deviation of the etching rate in all adjacent periods is within the deviation range threshold, the calibration ends; if it exceeds the deviation range threshold and the etching rate increases, increase the process coolant flow, replace the wafer and repeat the calibration process; if it exceeds the deviation range threshold, and the etching rate increases, increase the process coolant flow, replace the wafer and repeat the calibration process; If the deviation range threshold is reached and the etching rate decreases, reduce the process coolant flow rate, replace the wafer and repeat the calibration process; until the deviation of the etching rate in all adjacent periods is within the deviation range threshold;

When performing the glue removal process, it is necessary to add the predetermined glue removal time plus a preset remaining time as the complete glue removal time. During the entire complete glue removal time, process coolant with a calibrated flow rate is introduced into the cooling loop.

Further, the rapid temperature control slide stage further includes a temperature controller; the temperature sensor is connected to the signal input end of the temperature controller, and the output end of the temperature controller is connected to the electric heating wire.

Further, the rapid temperature control slide stage also includes an inlet pipe and an outlet pipe; the inlet of the cooling circuit is connected to the inlet pipe, and the outlet of the cooling circuit is connected to the outlet pipe.

Further, the cooling circuit is embedded in the surface of the base, and the partition is provided on the surface of the base and can close the top of the cooling circuit.

In a second aspect, embodiments of the present invention provide a degumming and etching equipment, including the rapid temperature control slide stage as described above, and a process chamber;

The bottom of the process chamber is provided with a pipeline inlet and outlet; the bottom of the base is connected to a hollow foot; the inlet pipe, outlet pipe, temperature sensor and temperature controller are all located in the inner space of the foot and can be removed from the pipeline. The inlet and outlet are led out; the lower port of the seat foot is butt assembled with the pipeline inlet and outlet, so that the process chamber can remain sealed.

Further, the degumming and etching equipment also includes a first valve and a second valve; one end of the first valve is used to connect the control gas, and the other end is connected to the inlet pipe; one end of the second valve is used to connect Pour in the process coolant and connect the other end to the inlet pipe.

Further, a one-way valve is provided between the first valve and the inlet pipe, and the conduction direction of the one-way valve is from the first valve to the inlet pipe.

In a third aspect, embodiments of the present invention provide a glue removal process, which is suitable for the glue removal and etching equipment as described above, and includes the following steps:

Steps to calibrate process coolant flow include:

Step S110: Make the process conditions in the process chamber meet the wafer degluing process conditions; the wafer degluing process conditions include: the heating layer is kept heated, the temperature of the heating layer is the first degluing process temperature, and the process chamber is first pumped. The vacuum is then introduced into the process gas and auxiliary gas;

Step S120: When the wafer degumming process starts, a preset time length is set. The preset time length is less than the predetermined degluing time but greater than 90% of the predetermined degluing time; an initial flow rate of process coolant is introduced into the cooling loop. Lower the temperature of the heating layer from the first degumming process temperature to the second degumming process temperature within a preset time period;

Measure the etching rate of the glue strip in at least three periods within the preset time period; compare the etching rates in each period;

Step S130, if the deviation of the etching rate in all adjacent periods is within the deviation range threshold, end the calibration; if it exceeds the deviation range threshold and the etching rate increases, increase the process coolant flow, replace the wafer and repeat step S110 Go to step S120; if it exceeds the deviation range threshold and the etching rate decreases, reduce the process coolant flow, replace the wafer and repeat steps S110 to S120; until the deviation of the etching rate in all adjacent periods is within the deviation range threshold Inside;

The steps to remove glue include:

Step S210: Make the process conditions in the process chamber meet the wafer degluing process conditions; add the predetermined degluing time plus a preset remaining time as the complete degluing time;

Step S220, during the entire complete glue removal time, introduce the calibrated flow rate of process coolant into the cooling loop;

Step S230, after the complete glue removal time is completed, control gas is introduced into the cooling circuit to blow out the process coolant in the cooling circuit;

Then proceed to the glue removal process of the next wafer.

Further, the second glue removal process temperature is 6°C to 10°C lower than the first glue removal process temperature.

Further, the preset remaining time is set to 4 to 6 seconds.

The beneficial effects brought by the technical solutions provided by the embodiments of the present invention are: during the wafer degluing process, the application can control the temperature of the wafer carrier to drop slightly by calibrating the flow rate of process coolant, thus offsetting the wafer degluing process. The increase in surface temperature leads to an increasing trend in the etching rate, and the degumming rate is controlled to basically achieve a uniform effect; on the premise of ensuring complete degumming, the remaining time after degumming is more accurately controlled to minimize the easily oxidized film. The degree of oxidation of the layer.

Description of the drawings

Figure 1 is a schematic structural diagram of a slide stage in the prior art.

FIG. 2 is a schematic diagram of the electrical structure of the slide stage and the glue removal and etching equipment in the embodiment of the present invention.

Figure 3 is a flow chart of the glue removal process in the embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

In the description of the embodiments of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" The orientation or positional relationship indicated by "" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or a specific orientation. orientation, construction and operation, and therefore should not be construed as limitations of the present invention. Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection or a fixed connection. Detachable connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also be an internal connection between two components; it can be a wireless connection or It's a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

As shown in Figure 2, first, a rapid temperature control slide stage proposed by an embodiment of the present invention includes:

Base 1, a cooling circuit 101 is distributed in the base 1, and the cooling circuit 101 is provided with an inlet 102 and an outlet 103;

Heating layer 2 is provided on the base 1;

Electric heating wire 3 is arranged in the heating layer 2;

The partition 5 is provided between the base 1 and the heating layer 2 for physically isolating the heating wire 3 and the cooling circuit 101; the partition 5 is a good conductor of heat;

Temperature sensor 4, the sensing part of the temperature sensor 4 passes through the barrier layer 5 and contacts the heating layer 2.

The electric heating wire 3 is roughly evenly arranged in the heating layer 2, for example, it can be arranged in a spiral or reciprocating manner; when performing the degumming process on the wafer surface, the wafer is placed on the heating layer 2, and the heating layer 2 is heated to the first degumming point. The temperature of the degluing process, the temperature sensor 4 can monitor the temperature of the heating layer 2; when the degluing process starts, a certain flow of process coolant is introduced through the inlet 102 of the cooling loop 101 to take away part of the heat to offset the constant heat generated on the wafer surface. Heat, control the flow of process coolant, so that the glue removal rate is basically uniform, which can prevent the remaining time after glue removal from being too long due to the increase in the glue removal rate, and minimize the easily oxidized film layer on the wafer degree of oxidation.

Further, the rapid temperature control slide stage also includes a temperature controller 6; the temperature sensor 4 is connected to the signal input end of the temperature controller 6, and the output end of the temperature controller 6 is connected to the electric heating wire 3; the temperature controller 6 can Set the heating temperature and control the heating power of the electric heating wire 3.

Further, the rapid temperature control slide stage also includes an inlet pipe 10 and an outlet pipe 11; the inlet 102 of the cooling circuit 101 is connected to the inlet pipe 10, and the outlet 103 of the cooling circuit 101 is connected to the outlet pipe 11; through the inlet pipe 10 The process coolant can be passed into the cooling circuit 101, and the process coolant in the cooling circuit 101 can be led out through the outlet pipe 11, and then returned to the cooling circuit 101 after external heat dissipation, forming a cooling cycle.

Specifically, the electric heating wire 3 is provided with an insulating layer on its surface; thus, both the heating layer 2 and the interlayer 5 can be made of metal layers; the heating layer 2 and the interlayer 5 can also be made of ceramic materials.

In one embodiment, the cooling circuit 101 is embedded in the surface of the base 1, and the partition 5 is disposed on the surface of the base 1 and can close the top of the cooling circuit 101; the cooling circuit 101 directly contacts the partition 5 to speed up the cooling process. heat exchange between the two.

As shown in Figure 2, an embodiment of the present invention also proposes a degumming and etching equipment, including the rapid temperature control slide stage as mentioned above, and a process chamber 200;

The bottom of the process chamber 200 is provided with a pipeline inlet and outlet 201; the bottom of the base 1 is connected to a hollow foot 104; the inlet pipe 10, the outlet pipe 11, the temperature sensor 4 and the temperature controller 6 are all located on the foot. 104, and can be led out from the pipeline inlet and outlet 201; the lower port of the foot 104 is butt assembled with the pipeline inlet and outlet 201, so that the process chamber 200 can remain sealed; the process chamber 200 is etching During the process, it is often necessary to maintain a certain degree of vacuum.

More preferably, the degumming and etching equipment also includes a first valve 7 and a second valve 8; one end of the first valve 7 is used to access the control gas, and the other end is connected to the inlet pipe 10; the second valve One end of 8 is used to connect to the process coolant, and the other end is connected to the inlet pipe 10; the connected control gas can be used as a temperature control gas to take away part of the heat. Another important function of the control gas is to remove glue from a wafer. After the process is completed, the process coolant in the cooling circuit 101 is quickly blown out; the temperature of the heating layer 2 can quickly rise to the first degluing process temperature to carry out the degluing process of the next wafer as soon as possible to improve efficiency; the first step above Valve 7 and second valve 8 can use pneumatic valves or solenoid valves;

More preferably, a one-way valve 9 is provided between the first valve 7 and the inlet pipe 10, and the conduction direction of the one-way valve 9 is from the first valve 7 to the inlet pipe 10; the one-way valve 9 can avoid When the first valve 7 is not closed, the process coolant mistakenly enters the air inlet pipeline of the control gas.

Based on the glue removal and etching equipment proposed in the above embodiment, the embodiment of the present invention also proposes a glue removal process, which includes the following steps:

Steps to calibrate process coolant flow include:

Step S110: Make the process conditions in the process chamber 200 meet the wafer degluing process conditions; the wafer degluing process conditions include: the heating layer 2 is kept heated, and the temperature of the heating layer 2 is the first degluing process temperature. The cavity 200 is first evacuated and then the process gas and auxiliary gas are introduced;

The temperature of the first degumming process depends on the specific photoresist, which is 200°C in this embodiment; the process gas is generally O2, and the auxiliary gas can be N2; the auxiliary gas can also include water vapor to remove the wafer before the degumming process. Chloride ions in the process;

Step S120, when the wafer degluing process starts, set a preset time length, which is less than the predetermined degluing time, but greater than 90% of the predetermined degluing time; pass an initial flow rate of process coolant into the cooling circuit 101 , reducing the temperature of the heating layer 2 from the first degumming process temperature to the second degumming process temperature within a preset time period;

Measure the etching rate of the glue strip in at least three periods within the preset time period; compare the etching rates in each period;

In this embodiment, the second glue removal process temperature is 6°C to 10°C lower than the first glue removal process temperature;

Step S130, if the deviation of the etching rate in all adjacent periods is within the deviation range threshold, end the calibration; if it exceeds the deviation range threshold and the etching rate increases, increase the process coolant flow, replace the wafer and repeat step S110 Go to step S120; if it exceeds the deviation range threshold and the etching rate decreases, reduce the process coolant flow, replace the wafer and repeat steps S110 to S120; until the deviation of the etching rate in all adjacent periods is within the deviation range threshold Inside;

The deviation of the etching rate can be expressed as the deviation rate, for example, the difference between the etching rate of a certain period and the etching rate of the previous period is divided by the etching rate of the previous period; the deviation range threshold can be set to ±0.5% or ± 0.3%;

The steps to remove glue include:

Step S210: Make the process conditions in the process chamber 200 meet the wafer degluing process conditions; add the predetermined degluing time plus a preset remaining time as the complete degluing time;

The default remaining time can be set to a few seconds, such as 4 to 6 seconds;

Step S220, during the entire complete glue removal time, pass the calibrated flow rate of process coolant into the cooling circuit 101;

Step S230, after the complete glue removal time is over, control gas is introduced into the cooling circuit 101 to blow out the process coolant in the cooling circuit 101;

Then proceed to the glue removal process of the next wafer.

In the above process steps, the process coolant or control gas can be switched through the first valve 7 and the second valve 8; the control gas can be N2 or Ar; because the predetermined degumming time and the predetermined time when calibrating the process coolant flow rate are The set time lengths are very close, so the etching rate within the predetermined degumming time period is basically the same as or has a very small deviation from the etching rate when calibrating the process coolant flow rate. The predetermined degluing time is slightly longer than the preset time when calibrating the process coolant flow rate. Coupled with the preset remaining time, it can ensure that each wafer in a batch can be completely deglued.

Embodiment 1

In the first embodiment, the first degumming process temperature is set to 200°C; the process gas is O2, and the auxiliary gas is N2 and H2O (gaseous); the process chamber 200 is first evacuated, and the pressure after the process gas and auxiliary gas are introduced is 600mt; the preset time for calibrating the process coolant flow is 60 seconds; the predetermined glue removal time can be 65 seconds; the process coolant flow is 2GPM; the photoresist that needs to be removed from the wafer is "TOKYO HKA KOGYO" CO., LTD.", the model is "TDMR-AR80 HP"; after the process coolant is introduced, the temperature of the heating layer drops from 200℃ to 190℃ within 60 seconds. In the first 20 seconds, the second 20 seconds and In the third 20 seconds, the etching rate of the glue removal is measured respectively, see Table 1;

Table I

As can be seen from Table 1, the etching rates in the three periods are 37297 Å/min, 37382 Å/min, and 37411 Å/min, and the deviation rates are 0.23% and 0.08% respectively; it can be seen that after entering 2GPM After the flow of process coolant, the gum removal rate basically reaches a constant speed.

Comparative Example 1

In Comparative Example 1, the first degumming process temperature is set to 200°C; the process gas is O2, and the auxiliary gas is N2 and H2O (gaseous); the process chamber 200 is evacuated first, and the pressure after the process gas and auxiliary gas are introduced is 600mt; no process coolant is introduced; a 60-second degumming process is performed; the etching rate of the degumming is measured in the first 20 seconds, the second 20 seconds, and the third 20 seconds. See Table 2. ;

Table II

As can be seen from Table 2, in the traditional 200°C constant temperature degumming process, as the wafer surface temperature continues to increase, the etching rate of the degumming shows an accelerating trend; the actual degumming time is difficult to grasp. If the remaining time is too long, for some process film layers that are easily oxidized, it is easy for an oxide film to form on the surface after the glue is completely removed.

Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the embodiments, those of ordinary skill in the art will understand that the technical solutions of the present invention can be Modifications or equivalent substitutions without departing from the spirit and scope of the technical solution of the present invention shall be included in the scope of the claims of the present invention.

Claims (5)

1. A glue removal process, suitable for a glue removal etching equipment, The degumming and etching equipment includes a rapid temperature control slide stage and a process chamber (200); The rapid temperature control slide stage includes: Base (1), a cooling circuit (101) is distributed in the base (1), and the cooling circuit (101) is provided with an inlet (102) and an outlet (103); The heating layer (2) is arranged on the base (1); Electric heating wire (3) is arranged in the heating layer (2); The partition (5) is provided between the base (1) and the heating layer (2), and is used to physically isolate the electric heating wire (3) and the cooling circuit (101); the partition (5) is a good conductor of heat; Temperature sensor (4), the sensing part of the temperature sensor (4) passes through the partition (5) and contacts the heating layer (2); Thermostat (6); the temperature sensor (4) is connected to the signal input end of the thermostat (6), and the output end of the thermostat (6) is connected to the electric heating wire (3); Inlet pipe (10) and outlet pipe (11); the inlet (102) of the cooling circuit (101) is connected to the inlet pipe (10), and the outlet (103) of the cooling circuit (101) is connected to the outlet pipe (11); The bottom of the process chamber (200) is provided with a pipeline inlet and outlet (201); the bottom of the base (1) is connected to a hollow foot (104); the inlet pipe (10), outlet pipe (11), The temperature sensor (4) and the thermostat (6) are both located in the inner space of the seat foot (104) and can be led out from the pipeline inlet and outlet (201); the lower port of the seat foot (104) is in contact with the pipeline inlet and outlet. (201) docking assembly to enable the process chamber (200) to remain sealed; The degumming and etching equipment also includes a first valve (7) and a second valve (8); one end of the first valve (7) is used to access the control gas, and the other end is connected to the inlet pipe (10); One end of the second valve (8) is used to access the process coolant, and the other end is connected to the inlet pipe (10); It is characterized by including the following steps: Steps to calibrate process coolant flow include: Step S110: Make the process conditions in the process chamber (200) meet the wafer degluing process conditions; the wafer degluing process conditions include: the heating layer (2) remains heated, and the temperature of the heating layer (2) is the first At the glue removal process temperature, the process chamber (200) is first evacuated and then the process gas and auxiliary gas are introduced; Step S120: When the wafer degluing process starts, a preset time length is set. The preset time length is less than the predetermined degluing time, but greater than 90% of the predetermined degluing time; the process of passing the initial flow rate into the cooling loop (101) The coolant reduces the temperature of the heating layer (2) from the first degumming process temperature to the second degumming process temperature within a preset time period; Measure the etching rate of the glue strip in at least three periods within the preset time period; compare the etching rates in each period; Step S130, if the deviation of the etching rate in all adjacent periods is within the deviation range threshold, end the calibration; if it exceeds the deviation range threshold and the etching rate increases, increase the process coolant flow, replace the wafer and repeat step S110 Go to step S120; if it exceeds the deviation range threshold and the etching rate decreases, reduce the process coolant flow, replace the wafer and repeat steps S110 to S120; until the deviation of the etching rate in all adjacent periods is within the deviation range threshold Inside; The steps to remove glue include: Step S210: Make the process conditions in the process chamber (200) meet the wafer degluing process conditions; add the predetermined degluing time plus a preset remaining time as the complete degluing time; Step S220, during the entire complete glue removal time, pass the calibrated flow rate of process coolant into the cooling circuit (101); Step S230, after the complete glue removal time is completed, control gas is introduced into the cooling circuit (101) to blow out the process cooling liquid in the cooling circuit (101); Then proceed to the glue removal process of the next wafer. 2. The glue removal process according to claim 1, characterized in that, The second glue removal process temperature is 6°C to 10°C lower than the first glue removal process temperature. 3. The glue removal process according to claim 1, characterized in that, The default remaining time is set to 4 to 6 seconds. 4. The glue removal process according to claim 1, characterized in that, The cooling circuit (101) is embedded in the surface of the base (1), and the partition (5) is provided on the surface of the base (1) and can close the top of the cooling circuit (101). 5. The glue removal process according to claim 1, characterized in that, A one-way valve (9) is provided between the first valve (7) and the inlet pipe (10), and the conduction direction of the one-way valve (9) is from the first valve (7) to the inlet pipe (10).