KR20070022820A - Use of an active wafer temperature control independent from wafer emissivity - Google Patents

Abstract

Embodiments of the present invention relate to a substrate or wafer edge support having an emissivity greater than that of a silicon wafer when the edge support supports the wafer during processing to form a circuit device in or on the wafer. These embodiments include a temperature sensor and a thermal conducting gas nozzle, and the temperature of the wafer and / or the edge support during annealing to reduce the degree of temperature roll off and temperature roll up at the edge of the wafer relative to the center of the wafer. Light energy is applied to sense and control. In particular, the use of an edge support having a radiation capacity greater than or equal to that of the wafer during processing reduces the temperature rollup or temperature rolloff during annealing of the helium gas jets directed to the edge support and / or wafer edge. You can. Since the wafers always have different radiative capacities in their different process and annealing positions, the use of a feedback loop allows one edge ring to provide a uniform annealing state of the wafer with radiative capacities with different ranges.

Description

USE OF AN ACTIVE WAFER TEMPERATURE CONTROL INDEPENDENT FROM WAFER EMISSIVITY

The present invention relates to the field of circuit device fabrication.

Maximizing the performance and yield of circuit devices formed on a substrate (such as integrated circuits (ICs), transistors, resistors, capacitors, etc., on semiconductor (eg, silicon) substrates) is the design, manufacture of equipment for manufacturing such devices. And important factors to be considered during operation. In transistor processes, it is common to increase the parameters to improve transistor performance. If the parameter crosses the threshold, the transistor will fail. The goal of transistor process engineering is to maximize performance without compromising yield. To create the maximum number of dies that meet these criteria, the uniformity of the process equipment needs to be optimized. For example, during the design and manufacture of a wafer processing chamber, such as a chamber with thermal spikes and annealing capabilities, the temperature of the substrate (eg, wafer) processed in the chamber needs to be maintained within a desired temperature threshold. Specifically, the equipment for manufacturing the circuit device must be able to maintain a uniform temperature along the substrate on which the circuit device is being formed during annealing, such as a spike annealing process.

Embodiments of the present invention will be described in an illustrative manner rather than a restrictive manner with reference to the accompanying drawings, in which like reference numerals designate like elements. In the detailed description that follows, only “an embodiment” does not necessarily refer to the same embodiment but means at least one embodiment.

1 is a cross-sectional view of a wafer processing system,

FIG. 2 is a graph plotting the temperature of the wafer versus distance along the surface of the wafer for a wafer having a higher emissivity than the emissivity of the wafer edge support;

FIG. 3 is a graph plotting the temperature of the wafer versus distance along the surface of the wafer for a wafer having a radiation ability less than that of the wafer edge support;

4 is a graph plotting the temperature of the wafer versus the distance along the surface of the wafer in the wafer having the same radiation power as that of the wafer edge support;

5 is a flow chart of an active temperature control process providing radiation independent of wafer temperature.

Various embodiments of the present invention provide a heating and cooling apparatus, system for heating and cooling an edge or edge support of a substrate or wafer on which a circuit device will be formed thereon or in a thermal process such as spike annealing or annealing a wafer or substrate. And methods. In addition, various embodiments of the present invention provide an edge support having a thermal mass greater than or equal to or less than the thermal mass or radiative capacity of the wafer or wafer surface (determined by radiance, mass and conductivity, and heating rate). It includes a chamber having a. The radiation capacity of the device or surface is defined as an index of the degree of light energy absorption expressed by 0-1. Thus, zero radiation refers to a surface that reflects all light incident on it (such as a fully reflective mirror), and radiation power of 1 indicates light incident on it (such as a fully black body). It represents the surface which all absorb. In other words, the reflectivity of the surface is (1-surface radiation).

The radiant heat processing chamber is a type of wafer processing chamber used during thermal processing operations. In one example of a radiant heat processing chamber, an edge ring or wafer edge support (referred to herein as "edge support") supports a substrate (eg, a wafer) on which an electronic circuit device is to be formed. This edge support supports the periphery of the substrate. The rest of this wafer is not supported.

1 is a cross-sectional view of a wafer processing system. 1 shows a system 100 having a wafer processing chamber 102 having an interior space suitable for receiving a wafer or substrate for processing (eg, a wafer or substrate having a diameter of 150 millimeters, 200 millimeters or 300 millimeters). do. Wafer 110 is supported by edge support 120 in chamber 102. According to an embodiment, the edge support 120 includes a variety of suitable materials, such as silicon carbide, ceramic, silicon or other thermally suitable materials with similar radiative capacity to silicon wafers.

According to an embodiment, the edge support 120 has a circle having a diameter larger than the diameter of the wafer to be processed on the edge support. Edge support 120 also has a generally flat surface, such as a circular surface, and has a flat circular disk shaped lip that defines the sheet or pocket on which the wafer to be processed on the edge support is to be placed. For example, the cross section of the edge support 120 at any point across its diameter defines an L shaped cross section, the base of which provides a support area such as the seat or pocket described above. The base of the L-shaped edge support extends 3 mm of its diameter so that the diameter can extend between 1 and 12 mm.

The edge support 120 also defines a cylindrical ring having an upper disk shaped step and a lower disk shaped step, for example the lower disk shaped step includes a seat, pocket or L-shaped base as described above, The upper disk shaped stepped portion has a larger diameter than the lower disk shaped stepped portion. In addition, the upper disc-shaped step may have an outer diameter to be fitted or connected on the support cylinder 122 or may be part of the support cylinder 122. The lower disc shaped stepped portion also has an inner diameter smaller than the outer diameter of the substrate or wafer and an outer diameter slightly larger than the outer diameter of the substrate or wafer. Thus, the lower disk shaped stepped portion has a size suitable for supporting the substrate or wafer, and the upper disk shaped stepped portion has a size suitable for supporting the substrate or wafer and the lower disk shaped stepped portion. The lower disk shaped stepped portion also has a support lip or support ring along its inner diameter to connect, contact or support the wafer or substrate.

In some embodiments, the lower disk shaped step, L-shaped base or support lip supports the wafer or substrate by contacting only a portion of the bottom or bottom surface of the wafer or substrate such that heat transfer between the edge support and the substrate or wafer is minimal. can do. In particular, the contact between the bottom or bottom surface of the substrate or wafer and the edge support defines a contact ring having an inner diameter that is approximately equal to its outer diameter. In addition, the inner and outer diameters of the contact ring exist between the inner and outer diameters of the lower disc shaped step.

In particular, the edge support 120 has a total width W1 between 2 and 30 millimeters by having a width W1 equal to one centimeter. Likewise, edge support 120 has an edge ring support width W2 between 1 and 12 millimeters by having a width W2 equal to 3 millimeters. Thus, edge support 120 has an exposed surface width W3 between 0 and 16 millimeters by having a width W3 equal to 7 millimeters. If the width W3 is zero, a structure other than the structures 122 and 120 shown in FIG. 1 is created. In addition, although the wafer 110 and the edge support 120 have a top surface having approximately the same height in FIG. 1, the top surface of the wafer 110 may be below or above the top surface of the edge support 120. . Likewise, the edge support 120 and the bottom or bottom surface of the wafer 110 are at different heights as shown in FIG. 1 and their shape is as shown in FIG. 1, but the edge supports disclosed herein ( 120) and other various shapes, heights, and / or orientations are possible. In addition, the edge support 120 may detachably attach or remove the wafer 110 (eg, include a geometric feature that makes the wafer slip, or a geometric feature that prevents the wafer from deviating from the support). Devices or features capable of connecting or supporting, holding, retaining or constraining wafer 110.

According to an embodiment, the wafer 110 includes or forms or deposits or grows monocrystalline silicon or polycrystalline silicon, or a silicon base or substrate such as a silicon wafer, silicon on insulator (SOI) or silicon on glass (SIOG). Wafers or substrates formed from various other suitable techniques for forming or any other type of wafer capable of forming electronic devices thereon, such as other wafers or substrates formed or cut or separated therefrom.

1 also shows an edge support 120 that may be supported, connected, attached, mounted on, or part of a support cylinder 122. The support cylinder 122 is connected to a drive assembly that rotates the support cylinder about an axis through the center of the support cylinder 122. According to an embodiment, the support cylinder 122, the edge support 120, and the wafer 110 rotate or rotate about an axis 115, such as the axis defined at the center 116 of the disk 110. For example, the wafer is provided with a wafer edge 112 that defines a circular, oblong, or other closed shape to provide a disk shape for the wafer 110. The edge support 120 also has a shape or edge support ring that matches the shape of the edge support 112 to support the wafer edge 112 by having a circular, oblong, or other closed shape. The chamber 102 is such as a plate having a surface facing the edge support 120 while generally reflecting the edge support 120 and the optical energy to which the wafer 110 is exposed to maintain the thermal state of the wafer 110. Reflector plate 104. The reflector plate 104 has a surface that is similar in size to the inner diameter of the support cylinder 122 and may or may not rotate as described above with respect to the rotation of the wafer 110.

In accordance with an embodiment, the system 100 includes a heater 130 inside or connected to or attached to the chamber 110 to direct light energy 132 to the wafer 110 and wafer edge support 120. According to an embodiment, the heater 130 directs the light energy uniformly against the surface of the wafer 110 and the surface of the edge support 120. For example, heater 130 includes an array of a number of individual heating lamps (eg, tungsten lamps) suspended over wafer 110 within chamber 102, which may include a plurality of zones grouped by radius ( For example, 14 or 15 zones). As such, heater 130 may be attached to the top or portion of chamber 102 such that wafer 110 may be disposed on and removed from edge support 120. In addition, chamber 102 is an opening, door or removable that allows wafer 110 to be removed from or disposed on edge support 112 without moving or placing heater 130 relative to chamber 102. Has a part. In addition, the lamp of the heater 130 can be focused so that the divergence angle of the emitted light can be controlled such that the light energy of the edge ring can be controlled without significantly affecting the temperature of the wafer. Heater 130 may be a power source, a power regulator, a mechanism for deciding or directing the light energy of heater 130 and / or the destination of the heater relative to wafer 110 and / or edge support 120 or It is connected to a controller that controls the direction and power.

Heater 130 also provides sufficient heat to perform annealing, bond annealing, and / or spike annealing of wafer 110 during the process of forming an electronic circuit device in or on wafer 110. Thus, the heater 130 may be subjected to annealing of the electronic circuit device on or in the wafer 110 (eg, by adjusting the temperature inside the chamber 102 through the delivered light energy and waiting for a period of time). Appropriate strength, duration, and / or focus may be provided on the top surface of the wafer 110 and / or edge support 120. For example, heater 130 heats wafer 110 such that location 114 or center 116 is a wafer temperature change curve selected over a period corresponding to the annealing, bond annealing and / or spike annealing processes as described above. Located in

System 100 is located within or in chamber 102 to direct heat conducting gas 152 at or near wafer edge 112 and / or adjacent wafer 110 and / or edge support 120. Connected or attached cooler 150. For example, FIG. 1 shows a simple embodiment of a cooler 150 that distributes gas (eg, through a hole through reflector plate 104) to direct heat conducting gas 152 to edge support 120. . According to an embodiment, the cooler 150 includes one or more gas nozzles, such as helium gas nozzles. For example, the cooler 150 may include one or more gas nozzles, gas supply tanks or reservoirs connected to one or more gas supply valves, a mechanism for directing, destination or focusing the output of the nozzles and / or wafers 110 and / or edges. A controller for controlling the flow and direction or destination of the gas injection port with respect to the support 120. For example, depending on the embodiment, the cooler 150 may be manufactured as one continuous ring, including for example one to several hundred gas nozzles or having a radius of at least 150 mm-W2 but less than 150 mm + W3. The diameter of this gas injection port can be smaller than 10 mm. Flow rate is less than 100 liters per minute. The exact flow rate depends on the diameter and number of nozzles. The cooler 150 also includes a gas nozzle having a nozzle focusing device made of exactly the same material as the reflector plate.

In addition, according to an embodiment, the system 100 is heated to direct light energy or other thermal energy to the surface and / or edge support 120 of the wafer 110 at or near the wafer edge 112. And attached to or included in the chamber 102. For example, FIG. 1 illustrates a heater 190 that is connected to or contained within chamber 102 that directs light energy 192 to edge support 120 and / or wafer edge 112. Heater 190 has one or more heating lamps as described for heater 130. This heater is built directly into the lamp head assembly of the heater 130 or exists as a separate unit as shown in FIG. For example, heater 190 may be moved relative to chamber 102 while placing wafer 110 on edge support 120 and being removed therefrom, connected to a power source and / or power regulator, and / or a heater ( And a mechanism for adjusting the focus or destination of the light energy of 190 and / or to control the power and direction or the destination of the heater 190 relative to the wafer 110 and / or the edge support 120. . Specifically, heater 190 includes one or more heating lamps that are irradiated in the same direction to concentrate radiant energy on a region that includes width W1 or on the region shown by width W1. These lamps emit an energy density that matches the energy density produced by the heater 130. For example, the lamps of heater 130 and / or are grouped into radiation zones for control. If the lamps of the heater 130 are irradiated sufficiently in the same direction, it may be sufficiently optimized to select individual lamps within a group to best affect the edge ring. If the lamps are not irradiated sufficiently in the same direction, these lamps may use a reflector sleeve modified to be irradiated in the sufficiently same direction.

In addition, although cooler 150 is shown positioned below wafer 110 and heater 130 and heater 190 is shown above wafer 110, coolers and heaters for wafer 110 and edge support 120 are shown. The position and orientation of may vary. For example, the cooler 150 may be located above the wafer 110 and the heater 190 may be located below the wafer 110. In addition, heater 190, cooler 150 and / or heater 130 may be located on the same side of wafer 110 by being positioned above wafer 110. The exact configuration may be selected such that the heater does not adversely affect the temperature measurement system of equipment such as sensors 160 and 170. In embodiments in which one or more heaters are located below the wafer and heater 130 is located above the wafer, a laser system or a filtered lamp system may be used, for example at the location of heater 190 so that the heater is used, for example, of equipment such as sensors 160, 170. It is possible to prevent interference with the detection wavelength of the temperature measurement system.

In addition, the systems, devices, and methods described herein may be used when wafer 110 and edge ring 120 are at a temperature different from the temperature during or after being heated by heater 130. For example, wafer 110 and edge ring 120 may be heated by heaters 130 and / or 190 and other heaters, cooled by cooler 150 and other coolers, internal heating of zones within chamber 120, or It may be at a different temperature during or after cooling or external cooling or heating of the chamber 102.

System 100 includes one or more temperature sensors that measure the temperature of the surface of wafer 110 and / or edge support 120. In the case shown in FIG. 1, temperature sensor 160 is connected or attached to chamber 102 to measure the temperature of the surface of wafer 110 or edge support 120 at or near wafer edge 112. Or exist within it. Similarly, the system 100 measures the temperature TC of the surface of the wafer 110 at a location 114 such as the location of the wafer 110 closer to the center 116 of the wafer 110 than the edge support 120. A temperature sensor 170 (or multiple units present at different radii) is included in or connected to the chamber 102. In one example, there are six different temperature sensors disposed radially between the temperature sensor 160 and the temperature sensor 170 such that the total number of temperature sensors is eight. Temperature sensor 160 and / or temperature sensor 170 is a pyrometer. Further, temperature sensor 160 and / or temperature sensor 170 may be disposed on or through reflector plate 104 as described above with respect to cooler 150. Similarly, temperature sensor 160 and / or temperature sensor 170 may be positioned and / or oriented relative to wafer 110 as described above with respect to the location and orientation of cooler 150. Specifically, for example, the temperature sensor 160 is placed within the radius defined by the edge support 120 (eg, by placing the sensor 160 in the same radius but in an offset position because the wafer rotates). Disposed or oriented to detect the temperature of the surface of 110. Further, sensor 170 is oriented or positioned to detect the temperature at the surface of wafer 110, including the temperature at center 116.

In accordance with an embodiment, the system 100 may include a wafer 110, such as a controller connected to the heater 130, the cooler 150, the heater 190, the temperature sensor 160 and / or the temperature sensor 170. A controller controls the heating and cooling and measures the temperature. Specifically, the controller 180 shown in FIG. 1 is attached or connected to the heater 130, the cooler 150, the heater 190, the temperature sensor 160 and / or the temperature sensor 170. The controller 180 may also be attached to other inputs, other outputs, other electronic devices and / or other equipment associated with the system 100 to participate in controlling the forming or processing of the device in or on the wafer 110. It is connected. For example, the controller 180 is connected or attached to a mechanism for directing or adjusting the focus of the light energy of the power source, power regulator or heater 130. In addition, the controller 180 is connected or attached to a mechanism for directing the output of the gas supply valve, gas supply tank or cooler 150 and / or directing the gas nozzle or adjusting the focus or destination. Finally, the controller 180 is attached or connected to a power source and / or power regulator and connected to a mechanism for directing, focusing or adjusting the light energy of the heater 130.

 The attachment or connection of the heater 130, the cooler 150, the heater 190, the temperature sensor 160, the temperature sensor 170, the controller 180 and / or other components described herein may be electronic. Interface type, connection type, attachment type, signal line type or signal circuit type. For example, such a method of attachment or connection may be, for example, data paths, links, wires, lines, printed circuit board traces, optical methods, infrared methods, any other various wired data conduits and / or any other various free spaces. It will be sufficient to electronically transmit various analog electronic data or digital electronic data through the data conduit.

Specifically, heater 130, cooler 150, heater 190, temperature sensor 160, temperature sensor 170 and / or controller 180 are placed on wafer 110 in chamber 102. Or to change the temperature of the wafer, wafer edge and / or edge support during forming or processing the device within. For example, the temperature of an edge support having an emissivity less than that of the wafer on the edge support is lower than the temperature of the wafer during or after heating through the light energy and heat is conducted from the edge of the wafer during or after such heating. . As such, the wafer and edge support have a thermal response related to the thermal mass and the radiation capacity of the wafer and the edge support. In addition, the thermal response, heating rate and / or thermal conductivity of the wafer and the edge support may be determined by the material, thickness, emissivity, thermal coefficient, thermal resistance and / or thermal uniformity of the wafer support. And, depending on the degree of thermal resistance and / or thermal uniformity, or inconsistent with, or non-uniform with one another. In addition, heat transfer, such as heating or cooling, may occur between the edge support and the wafer because the edge support is in thermal contact with the wafer, or is attached to, attached to the wafer, or supports, holds, or constrains the wafer. .

In the case shown in FIG. 1, the edge support 120 has an actual or predicted heating rate that depends on the combination of the thermal mass and the top surface emissivity of the edge support 120. Similarly, wafer 110 has an actual or predicted heating rate that depends on the combination of the thermal mass and the top surface emissivity of wafer 110. Thus, due to the difference between the emissivity, thermal mass or heating rate of the edge support 120 and the emissivity, thermal mass or heating rate of the wafer 110, the top surface of the edge support and the top surface of the wafer are exposed to light energy. As a result, the edge support and the wafer have different temperatures, thereby allowing heat to be transferred between the edge support and the wafer edge 112. As a result, the temperature of the wafer 110 at or near the wafer edge 112 is greatly reduced during the annealing process such that the performance, yield, and speed of the electronic device formed at or near the edge 112 of the wafer 110. Is lowered. Specifically, because these devices are not at or close to optimal temperatures for devices closer to the center during the given process of forming these devices, these devices contain defects or imperfections or provide optimal performance. You will have worse performance.

In particular, even if the edge support is thermally adjusted to match the radiation capacity of the silicon wafer during annealing or spike annealing, the temperature becomes uneven at the edge of the wafer if the wafer has a different heating rate than the edge support. This temperature nonuniformity degrades the device's performance near the edge of the wafer and also reduces yield. The controller 180 receives temperature data from the temperature sensors 160 and 170 to control cooling and heating of the wafer 110 through the heaters 130 and 190 and the cooler 150. For example, the controller 180 may heat the wafer 110 and / or the edge support 120 as part of a method of forming or processing a device in or on the wafer 110 taking into account data or responses from the temperature sensors 160, 170. And cooling by monitoring. The device forming or processing method includes annealing step, junction annealing step, spike annealing step, controlling the intensity, duration and focus of heating through heater 130, and determining the intensity, duration and focus of heating through heater 190. Controlling, controlling the intensity, duration, and focus of cooling through the cooler 150, adjusting the temperature in the chamber 102 to cool the wafer 110 and waiting for a predetermined period of time, the wafer 110 Controlling the rotational speed of the substrate and / or including the process described below with reference to FIG. 4 and various other steps associated with forming or processing a device on or within the wafer 110.

In addition, as described above, a surface such as the upper surface of the edge support 120 has the same radiation as, a higher radiation or a smaller radiation than the surface such as the upper surface of the wafer 110. Have In the following description, for the sake of simplicity, the thermal masses are considered equal. For example, if the thermal mass of the edge ring is twice the thermal mass of the wafer, the edge ring cools faster than the wafer even if the edge support ring has a higher radiation capacity. The combination of thermal mass and radiative capacity is an important parameter. If the emissivity of the edge support 120 is smaller, the edge support 120 cools faster than the wafer edge 112 so that heat is transferred from the wafer edge 112 so that the temperature of the wafer edge 112 is reduced. For example, during or after heating the wafer 11 and the edge support 120 by the heater 130, if the edge support 120 has an emissivity less than the emissivity of the wafer 110, the wafer 110. The temperature of the edge 112 of the lower edge 112 is lower than the temperature at the position 114, so that the edge temperature of the wafer 110 is lowered in a curved form (the curved lower temperature is subsequently rolled off. Refer to).

In particular, FIG. 2 is a graph plotting the temperature of the wafer versus the distance along the surface of the wafer for a wafer having higher radiation than that of the edge support. FIG. 2 shows the temperature gradient 230 plotted against the temperature 220 and the distance 220 along the cross section of the wafer (eg, such as the distance along the cross section of the wafer 110 shown in FIG. 1). For example, the temperature gradient 230 may be a temperature gradient during heating (eg, during annealing or spike annealing) the wafer 110 and the edge support 120 by the heater 130. In addition, temperature gradient 230 heats wafer 110 and / or edge support 120 by heater 190 and then cools wafer 110 and / or edge support 120 by cooler 150. Temperature gradient during or after.

Specifically, as shown in FIG. 2, edge DE1 represents the left edge of wafer 110 (eg, edge 112 on the left side of wafer 110), and axis DA represents the center of wafer 110 ( 116, the edge DE2 represents the right edge of the wafer 110 (eg, the edge 112 at a location directly across the wafer center 114 from DE1). Thus, FIG. 2 shows, for example, that the edge support 120 has less radiation than that of the wafer 110 so that the wafer edge (while or after heating the wafer 110 and the edge support 120 by the heater 130 ( The temperature gradient 230 with the wafer edge temperature roll off 240 at or near the edges DE1, DE2 in the case where heat is conducted from DE1, DE2. Thus, heater 190 may be used to irradiate light energy 192 towards wafer edge 112 and / or edge support 120 to remove, correct or reduce wafer edge temperature roll off 240. Able to know.

Similarly, the wafer 110 may have a temperature higher than the temperature of the wafer edge 112 (eg, due to the difference in emissivity, so that heat is conducted from the edge support 120 to the wafer edge 112). As is the case, if the edge support 120 has a greater emissivity than the emissivity of the wafer 110, the wafer edge temperature rolls up (the temperature rises in a curved form). Thus, during or after heating the wafer 110 and the edge support 120 by the heater 130, the wafer 110 has a wafer edge 112 at a temperature higher than the temperature at the location 114. Experience edge temperature roll up.

For example, FIG. 3 is a graph plotting the temperature of the wafer versus distance along the surface of the wafer in the case of a wafer having a radiation capacity less than that of the wafer edge support. 3 shows a temperature gradient 330 plotted against temperature 310 versus distance 320 in the case of a wafer 110 having an emissivity lower than the emissivity of the edge support 120. For example, the temperature gradient 330 may be a temperature gradient during or after heating (eg, annealing or spike annealing) the wafer 110 and the edge support 120 by the heater 130. The temperature gradient 330 may also be a temperature gradient during heating and / or cooling of the wafer 110 and / or the edge support 120 by the heater 190 and / or the cooler 150.

In this case, as shown in FIG. 3, the wafer emissivity is less than the edge support emissivity, so that heat is transferred from the hotter edge support 120 to the wafer, thereby resulting in edges DE1 and DE2 relative to the temperature at the axis DA. The temperature of the wafer at or near will rise. Thus, FIG. 3 shows edge DE1 as in the case where heat is transferred from edge support 120 to wafer edges DE1 and DE2 during or after heating wafer 110 and edge support 120 by heater 130. And temperature gradient 330 with wafer edge temperature roll up at or near DE2. In this case, a cooler 150 is used to cool the wafer edge 112 by directing the heat conducting gas 152 to the wafer 110 or edge support 120 at or near the wafer edge 12. Wafer edge temperature roll up 330 is removed or reduced.

FIG. 2 shows similar roll off 240 for edge DE1 and edge DE2, but edge DE 2 differs from edge DE 1 depending on the device or part of the device formed at or near edge DE1 and DE2. You will also recognize that you can. Similarly, it is contemplated that the temperature roll up for edge DE 2 may or may not be the same as for edge DE 1 for similar reasons.

4 is a graph plotting the temperature of the wafer with respect to the distance along the surface of the wafer in the wafer having the same radiation power as that of the wafer edge support. For example, FIG. 4 shows the temperature of the wafer versus the distance along the wafer or its surface with radiation power consistent with that of the wafer edge support. This coincidence tolerance depends on the peak temperature, the heating rate, the radiative power difference and the thermal mass of the wafer and edge support. Thus, FIG. 4 shows the temperature gradient 430 plotted as a function of the distance 420 versus the temperature 410 for the wafer 110. 4 is for the case where the radiative capacity of the edge support 120 coincides with, corresponds to, or is approximately the same as the radiative capacity of the wafer 110. Thus, in FIG. 4, the edge support 120 may have the same or nearly the same temperature because the wafer and the edge support have the same or nearly the same radiative power to each other during or after the wafer 130 is heated by the heater 130. And no temperature shift between the wafer 110 will occur. As noted above, in the case shown in FIG. 4, devices along the surface of the wafer 110 experience similar thermal treatments during processing or forming electronic devices on or within the wafer 110 such that yields of such devices and And / or performance is improved.

In conclusion, in accordance with embodiments of the present invention, a method or instruction (eg, a computer processor) for controlling the processing of wafer 110 and forming devices in or on wafer 110 and for controlling thermal processing of wafer 110. Is performed by reducing the wafer edge temperature roll off shown in FIG. 2 and / or reducing the wafer edge temperature roll up shown in FIG. 3 so that a temperature gradient of wafer edge temperature is shown in FIG. Heating and cooling edge support 120 and / or wafer edge 112 to be similar to temperature gradient 430.

For example, FIG. 5 is a flow chart of an active temperature control process that provides a wafer temperature independent of emissivity. In accordance with an embodiment, any or all of the blocks to be described below with respect to FIG. 5 may be devices or portions of devices on or within a wafer as disclosed herein (including, for example, annealing processes and / or spike annealing processes). Included in a method and / or instruction (eg, executed by a computer processor) to form a C. At block 510, the wafer is placed on an edge support of the wafer processing chamber. For example, wafer 110 is disposed on edge support 120.

Wafer 110 includes a partially or fully formed device or portion of a device (eg, a transistor, resistor, capacitor, etc.) as described with respect to FIG. 1. Wafer 110 includes a film stack, device layers, doped material, contacts, and the like. For example, processing of the wafer 110 prior to block 510 is to change the emissivity, such as the upper side emissivity of the wafer 110. For example, if the device is formed on the wafer 110, the radiation capacity of the wafer 110 is increased.

Next, at block 530, the wafer and edge support are heated. For example, wafer 110 and edge support 120 are heated by heater 130 during or after forming devices such as transistors, resistors, capacitors, and the like on the wafer as described in block 510. Thus, the heater 130 exposes the wafer 110 and the edge support 120 to light energy sufficient to increase the temperature of the wafer and the edge support so that if the radiation capacity of the wafer differs from that of the edge support, As described above, heat transfer occurs between the edge support 120 and the wafer 110. As such, heater 130 heats wafer 110 and edge support 120 such that wafer edge 112 has a temperature that is greater or less than the temperature at location 114 or center 116. Specifically, block 530 includes an annealing process, such as an annealing process, a junction annealing process, and / or a spike annealing process that occurs during the process flow of forming or processing a device on or in wafer 110.

At block 530, the wafer and edge supports are optionally cooled as time decreases or controls and the time elapses within chamber 102. Further, at block 530, heat transfer occurs between the edge support 110 and the wafer 120, such as between the edge support 120 and the wafer edge 112, as described herein above. Such heat transfer may occur during or after heating of the wafer and edge support as described above.

At decision block 560, it is determined whether the temperature of the wafer has cooled further than the temperature of the edge support. For example, a measurement of temperature TC at position 114 by temperature sensor 170 may be performed by temperature sensor 160 at or near edge support 120 or wafer 110 or wafer edge 112. The temperature TES is compared with the measured value. If the wafer was cooled further than the edge support at decision block 560, the process proceeds to block 570 where the edge support or wafer edge is cooled. This allows the outer edge in the radial direction of the wafer on the edge support 120 during or after the heating of the wafer as described above in block 530 by cooling the surface or edge support of the wafer at or near the wafer edge 112. Is cooled. For example, FIG. 1 shows a cooler 150 that cools the edge ring 120 by a thermally conductive gas 152. The cooling step at block 570 includes cooling the edge support 120 such that the temperature of the wafer edge 112 is reduced by thermal energy conduction between the wafer edge 112 and the edge support 120. do. For example, depending on the embodiment, the temperature of the wafer edge 112 is within 2 ° C., within 5 ° C., within 10 ° C., 15 ° C. with the temperature of the wafer 110 at the location 114 or the center 116. Edge support 120 or wafer edge 112 is cooled to be the same within or within 20 ° C. After block 570, the process returns to block 530.

If the wafer was not cooled further than the edge support at decision block 560, the process proceeds to block 580. At decision block 580, it is determined whether the wafer is hotter than the temperature of the edge support. The temperature determination process at block 580 is similar to the temperature determination process described for block 560. If it is determined at block 580 that the wafer is hotter than the edge support, the process proceeds to block 590 where the edge support and / or wafer edge 112 is heated. For example, heater 190 directs light energy 192 to edge support 120 and / or wafer edge 112 as described above in FIG. 1. After block 590, the process proceeds to block 530.

If the wafer is not hotter than the edge support at block 580, the process returns to block 530. Alternatively, the process terminates when the step of processing or forming a device, such as in or on wafer 110, is complete.

Blocks 560, 570, 580, 590 may occur during block 530 to provide active temperature control during heating of the wafer and edge support. Likewise, blocks 560 through 590 may occur after block 530 while cooling the wafer and edge support over a period of time. In addition, according to an embodiment, the process shown in FIG. 5 may include only blocks 560 and 570 without including blocks 580 and 590 or alternatively may include only blocks 580 and 590 and not include blocks 560 and 570. .

Note that all or any of blocks 530-590 of FIG. 5 can be included within the method or feedback loop as described for system 100 or controller 180. In addition, blocks 530-590 may be implemented by a method of controlling system 100 by controller 180 or one or more sets of computer instructions.

  Thus, in accordance with an embodiment, the system 100 or controller 180 controls the thermal processing of the wafer 110 by controlling the cooling and heating of the wafer through the heaters 130, 190 and / or the chiller 150. And / or implement or include instructions. For example, system 100 or controller 180 (including, for example, a processor disclosed herein that can implement machine readable instructions) may be a processor (eg, a computer processor, digital signal processor, computer or other hardware or software control). And / or a machine-readable medium that is accessed by a possible device to implement a set of methods or instructions (including, for example, computer software, computer instructions, or hardware circuitry or logic) disclosed herein. As such, the system 100 or controller 180 may implement an instruction or method to control the heater 130 that heats the wafer 110 such that the temperature of the location 114 is within a selected wafer temperature change curve for a predetermined period of time. Can be. For example, the method or instruction may be used to heat the wafer as described above with respect to block 530 of FIG. The wafer may be heated to be within the selected wafer temperature change curve for a predetermined period of time. In particular, the instruction or method may provide a temperature of 150-700 ° C. (eg, 500 ° C.) for temperature stabilization that causes the wafer 110 and edge support 120 to activate a closed loop control prior to the spike phase. ) Can be heated to a temperature that increases by 80 to 1000 ° C. per second (eg, by 200 ° C. per second) for 2 to 10 seconds (eg, the temperature of the wafer and edge support to 1000 ° C. for 5 seconds). This heating is then stopped.

Similarly, system 100 or controller 180 may provide edge support 120 and / or wafer edge 112 such that the temperature of the edge support or wafer edge is within a selected wafer edge or edge support temperature change curve for a predetermined period of time. Implements an instruction or method of controlling the cooler 150 to cool the position of the wafer 110 at or near. As such, as described above with respect to heating by the heater 130, this instruction or method causes the cooler 150 to direct the heat conducting gas 52 to the edge support 120 and / or the wafer 110. The temperature of wafer edge 112 will be within a threshold temperature difference value selected for the temperature of wafer 110 at location 114 or center 116 during the wafer temperature change curve described above.

 Similarly, system 100 or controller 180 may provide edge support 120 and / or wafer edge 112 such that the temperature of the edge support or wafer edge is within a selected wafer edge or edge support temperature change curve for a predetermined period of time. Implements an instruction or method of controlling the heater 190 to heat the position of the wafer 110 at or near. Thus, as described above with respect to heating by heater 130, this instruction or method causes heater 190 to direct light energy 192 to edge support 120 and / or wafer 110. The temperature of the wafer edge 112 will be within a threshold temperature difference value selected for the temperature of the wafer 110 at the location 114 or the center 116 during the wafer temperature change curve described above.

An edge temperature change curve that is outward in the selected edge support, wafer edge, or radial direction is 2 ° C., 5 ° C., 10 ° C. 15 ° C., or 20 ° C. of the temperature of the wafer 110 at the location 114 or the center 116. It is a curve intended to maintain the temperature of edge support 120 or wafer edge 112 into. This exact temperature tolerance is considered to be governed by process requirements. Specifically, the method or instruction may be a wafer instead of the temperature of the wafer edge (such as, for example, wafer edge 112 and / or wafer edges DE1 and DE2) not experiencing a temperature off 240 or a temperature roll up 250. Heater 130, 190 and / or cooler 150 are controlled to have a temperature gradient similar to temperature gradient 430 shown and described with respect to FIG.

For example, the system 100, controller 180, instructions, or method described herein may, for example, heat the wafer 110 and / or edge support 120 by controlling the heaters 130, 190 and / or the cooler 150. And measurements from temperature sensors 160 and / or 170 to control cooling. For example, this control step may implement a feedback loop that includes measurements from temperature sensors 160 and 170 to control cooling and heating of wafer edge 112 through heater 190 and cooler 150. Alternatively, this control step controls the intensity and duration of heating and cooling by heaters 130, 190 and cooler 150 and is placed on one or more edge supports (eg, similar to edge support 120 but with multiple radiation). Instructions or methods derived from trial and error testing using one or more wafers (e.g., multiple wafers with varying top side radiative capacity) tested inside chamber 102, disposed on multiple edge supports having Implement

Further, according to an embodiment, this control step of implementing the instructions derived from the feedback loop or the trial and error test may be based on the emissivity of edges that are outward in the radial direction of the wafer and outward in the radial direction of the wafer. The thermal density of the edge present, the radiation capacity of the edge support, the thermal density of the edge support, the heating capacity of the first heater 130, the cooling capacity of the cooler 150, and the second heater Consider at least one of a heating capacity of 190, a heating zone of the first heater 130, a cooling zone of the cooler 150, and a heating zone of the second heater 190 (eg, the In the heating zone a portion of the wafer 110 and / or edge support 120 is heated and / or cooled).

Next, according to an embodiment of the present invention, the temperature of the wafer 110 relative to the edge support 120 can be controlled by selecting the edge support 120 having the desired actual or predicted radiation. As described above, the radiation capability of the edge support 120 approximates how the temperature of the wafer edge 112 is at the temperature of the location 114 or the center 116 during or after heating of the wafer 110 and the edge support 120. Known radiation power (eg, through an experiment based on known radiation power (eg, wafer edge temperature roll off) of wafer 110 (such as, for example, the predicted top side radiation power of wafer 110). ), The radiation capacity of the edge support can be selected. For a particular wavelength 900 nm, pure silicon wafers have an upper side radiation of 0.6 and nitride coated silicon wafers have a radiation of 0.9. In addition, as discussed above, the emissivity of a wafer decreases / increases during formation or partial formation of a device on or within this wafer. In addition, the edge support 120 may be selected to have an actual or predicted emissivity with a desired relationship with the emissivity of the wafer after forming or processing the device on the wafer.

In the case of certain process flows, the radiative capacity of a silicon wafer having a device formed thereon or in it may differ significantly from that of a pure silicon wafer. Therefore, in addition to controlling the cooling and heating of the wafer and the edge support as described above, the edge support (e.g., By including such edge supports in the system 100). For example, the edge support 120 may have radiation or radiation of the wafer that provides a heating rate that matches the heating rate of the wafer 110 after all or some processing necessary to form the device on or within the wafer 110. It can have the same radiation power as the Thus, the edge support 120 will have an adjustable or uniform radiation power to match the radiation power of the wafer 110 after forming the desired device on or within the wafer 110. Importantly, the edge support 120 is a wafer such that the temperature gradient along the wafer 110 coincides with the temperature gradient 430 shown and described in FIG. 4 during or after forming the desired device on or within the wafer 110. It can have a selected emissivity which is related to the emissivity of.

In addition, the step of selecting the edge support 120 or determining whether the radiation power of the edge support 120 coincides with the radiation power of the wafer 110 may include radiation power, thermal mass, and heat of the edge support and the wafer. Considering at least one of conductivity, heating rate, light energy absorption rate, thermal reactivity, thermal resistance, specific heat, degree of temperature roll-off, degree of temperature rollup, and edge effects. In addition, the above-described selection step or determination of conformity step may be performed by a device or device portion, processing, heat treatment, method, instruction, copy, to be formed on the wafer 110 during the period in which the wafer 110 is to be processed in the chamber 102. Trial and error tests to find the radiative capacity of the desired edge support, taking into account the capabilities, device density and device type. As such, the edge support 120 may be selected to have a radiation capacity that initially matches that of the wafer 110 during or after processing the wafer 110 or after completing the device on or in the wafer 110.

In particular, according to an embodiment, the edge support 120 may have a radiation capacity that is greater than, equal to, or less than the expected radiation power of the wafer 110 during or after processing the wafer on the edge support 120. In addition, the edge support 120 may be at least 2 percent, 5 percent, 10 percent, 15 percent less than the expected emissivity of the top surface of the wafer 110 during or after forming the device in or on the wafer 110. It can have radiation as large or small as 20 percent or 25 percent. In addition, the edge support 120 may have a radiative capacity that is less than, equal to, or greater than 0.7, 0.75, 0.775, 0.8, 0.825, 0.85, 0.875, 0.9, 0.925, or 0.95. In addition, the edge support 120 can have a top surface radiance that is within 10 percent of the top surface radiance of the wafer 110 during or after forming an electronic device on or in the wafer 110. The magnitude of this tolerance (offset) will be determined by the edge ring cooler and heater.

Matching wafer emissivity is complicated because the emissivity of the product wafer can vary due to the location of the annealing step in the process flow or the change of the film stack in subsequent process techniques. For a particular process flow and step location, the edge support is a real or predicted relationship that matches or matches a given or actual radiated power of the wafer at a given point in time during the formation or processing of the device or part of the device on the wafer. It can be selected to have a radiated capacity. If more than one annealing step is present, it becomes difficult to use one piece of equipment for two different annealing steps if the wafer emissivity is different in two steps. One important technical idea for this application is the feedback loop of the heater / cooler, which allows one device and edge ring to be adapted for one or more wafer emissivity.

In addition, according to an embodiment, the selecting step of the edge support 120 or the step of determining whether the radiation support between the edge support 120 and the wafer 110 coincides may include a control, an instruction, a method, a feedback loop, and a trial and error test. And the same consideration of the factors as described for the instruction or method for the system 100 or the controller 180.

For example, the step of selecting the edge support 120 or determining whether the radiation support between the edge support 120 and the wafer 110 is consistent may be performed prior to the inclusion of the edge support 120 in the chamber 102. This may be a factor taken into account while controlling the heating and cooling of the wafer 110 by the system 100 or controller 180 disclosed herein. Similarly, the selecting step of the edge support 120 or the step of determining whether the radiation support between the edge support 120 and the wafer 110 coincides may be performed before the block 510 of FIG. 5.

In the foregoing detailed description, certain embodiments have been described. However, various modifications and changes to these embodiments can be made without departing from the broader scope and spirit of the embodiments defined in the claims. Therefore, the detailed description and drawings should be construed as illustrative dimensions rather than limiting the present invention.

Claims (23)

Cooling the edge of the wafer supported by the edge support in the wafer processing device while heating the wafer; Way. The method of claim 1, The cooling step includes cooling the edge of the wafer to a temperature within 10 ° C. of the temperature of the center of the wafer. Way. The method of claim 1, Heating the wafer and the edge support sufficiently to cause heat transfer between the edge of the wafer and the edge support; Way. The method of claim 3, wherein The cooling step includes cooling the edge support sufficiently to cool the edge of the wafer by heat transfer between the edge of the wafer and the edge support. Way. The method of claim 1, Further comprising forming a plurality of devices or portions of devices on the wafer prior to heating and cooling Way. The method of claim 5, wherein Selecting the edge support from the plurality of edge supports for use with the wafer processing device, The selecting step includes matching a heating rate of the wafer with a heating rate of the selected edge support. Way. The method of claim 6, The matching step may include radiating capacity, thermal mass, thermal conductivity, heating rate, light energy absorption rate, thermal reactivity, thermal resistance, specific heat, temperature roll off degree, and temperature roll up of the edge support and the wafer. Considering at least one of a degree and an edge effect Way. The method of claim 4, wherein Heating the edge support and the wafer with light energy; Way. The method of claim 8, The heating step includes joint annealing and spike annealing Way. The method of claim 8, The heating step includes exposing the wafer and the edge support to a sufficient amount of light energy such that the edge support has a first temperature and the wafer has a second temperature different from the first temperature. Way. An edge support having a size suitable for supporting a wafer in the processing chamber, The edge support has an emissivity greater than or equal to the predicted emissivity of the wafer selected for processing on the edge support. Device. The method of claim 11, The edge support has a first heating rate that depends on the top surface emissivity and thermal mass of the edge support, The wafer has a second heating rate that depends on the top surface emissivity and thermal mass of the wafer and is different from and predicted of the first heating rate, The difference between the first heating rate and the second heating rate is that the edge support has a first temperature and the wafer has a second temperature that is different from the first temperature such that the top surface of the edge support and the top surface of the wafer are different. Exposure to light energy is large enough to cause heat transfer between the edge support and the edge of the wafer. Device. The method of claim 11, Further comprising a wafer supported by the edge support, The edge support has an upper surface radiance that is within the radiance offset by a predetermined amount from the upper surface radiance of the wafer after forming a plurality of electronic devices on the wafer, The predetermined size is determined by the edge ring heating capacity or cooling capacity Device. A system comprising a wafer processing chamber, The wafer processing chamber is An edge support and a support having a size and a first emissivity sufficient to support a wafer thereon, wherein the edge support is a support having a second emissivity greater than the first emissivity;  A heater connected to the wafer processing chamber to direct light energy to the wafer and the edge support; A cooler connected to the wafer processing chamber to direct heat conducting gas to the edge support; system. The method of claim 14, A controller connected to the heater and the cooler to control heating of the wafer by the heater and cooling of the edge support by the cooler; system. The method of claim 15, The controller includes a feedback loop having a first temperature sensor for measuring the temperature of the edge support and a second temperature sensor for measuring the temperature at a location of the wafer located closer to the center of the wafer than the edge support. system. The method of claim 14, And a second heater connected to the chamber to direct light energy to the edge support. system. The method of claim 17, The second heater comprises at least one heating lamp having its light energy focus at an edge that is outward in the radial direction of the wafer, The heating lamp is a broadband light source or laser system. The method of claim 14, The cooler includes at least one helium (He) gas nozzle system. A product comprising a machine readable medium stored therein that is accessed by a processor to implement a method of heating and cooling a wafer supported by an edge support in a wafer processing device, the method comprising: The method, a) a first heater that heats the wafer such that the temperature at the location of the wafer that is closer to the center of the wafer than the edge that is outward in the radial direction of the wafer remains within a selected wafer temperature change curve for a predetermined period of time. Controlling, b) controlling a cooler to cool the edge support such that the temperature of the edge support is within the selected edge support temperature change curve for the predetermined period of time;  c) outward in the radial direction of the wafer such that the temperature of the edge outwardly in the radial direction of the wafer is within the selected temperature change curve of the edge outwardly in the radial direction of the wafer for the predetermined period of time. Controlling a second heater for heating the edges; product. The method of claim 20, The steps a) to c) may be performed at a temperature within 10 ° C. of the temperature at the position of the wafer located closer to the center of the wafer in the radial direction of the wafer during the predetermined period. Including adjusting product. The method of claim 20, The steps a) to c) include a feedback loop having at least two temperature sensors measuring the temperature at the edge support and the position of the wafer located closer to the center of the wafer; One of the instructions derived from trial and error testing using a wafer disposed on the edge support. product. The method of claim 20, The method is characterized in that the radiative capacity of the outer edge in the radial direction of the wafer, the thermal density of the outer edge in the radial direction of the wafer, the radiative capacity of the edge support, the thermal density of the edge support, A heating capacity of the first heater, a cooling capacity of the cooler, a heating capacity of the second heater, a heating zone of the first heating device, a cooling zone of the cooler, and a heating zone of the second heater. To consider at least one of product.

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