JP2009539270A - System and method for semiconductor processing - Google Patents

Abstract

  Disclosed is a system and method for performing semiconductor processing using a processing chamber, a flash lamp adapted to be triggered repeatedly, and a controller connected to the control input of the flash lamp to trigger the flash lamp. . The system can deploy a solid state plasma source in parallel with the flash lamp in wafer processing.

Description

The present invention relates to semiconductor processing.
This application claims priority to US patent application Ser. No. 11 / 443,620 filed May 31, 2006, and this application is US Patent Application Ser. No. 11 / 443,621 filed May 31, 2006. Claiming priority.

  The manufacture of modern semiconductor device structures traditionally relies on plasma processing in various operations such as etching, deposition or sputtering. Plasma etching involves removing material from a substrate using chemically active atoms or high energy ions. Plasma enhanced chemical vapor deposition (PECVD) can lower the temperature of a substrate during deposition by dissociating and activating gas using plasma. Plasma sputtering also deposits material on the substrate, where plasma ions such as argon strike the material surface and sputter the material, which is carried to the substrate as neutral atoms. Additional plasma processes include plasma surface cleaning and physical vapor deposition (PVD) of various material layers.

  Typically, the plasma is generated using a radio frequency operated plasma source. In a “typical” radio frequency operated plasma source, alternating current (AC) power is rectified and switched to supply current to the RF amplifier. The RF amplifier operates at a reference frequency (eg, 13.56 MHz) and passes current through the output matching network and then through the power metering circuit to the output of the power supply. The output matching section is usually designed to be connected to a generator optimized to operate at a specific impedance, for example 50 ohms, so as to have the same characteristic impedance as a coaxial cable commonly used in industry. Power flows through the matching cable cross section, is measured by the matching controller, and is converted by the load matching section. The load matching unit is usually a motorized automatic tuner, so the operation of the load matching unit introduces a predetermined time delay before the system is properly configured. After passing through the load matching section, power is then directed to a plasma excitation circuit that drives the two electrodes in the exhaust processing chamber. Plasma is generated when processing gas is introduced into the exhaust processing chamber and driven by the circuit. Since the matching network or load matching unit is motorized, the response time from the matching network is typically on the order of 1 second or more.

  Usually, the plasma is generated continuously in order to obtain a large amount of energy necessary for depositing the layer at a high speed and improving the shape (coverage) of the stepped portion. As described in US Pat. No. 5,468,341 entitled “Plasma Etching Method and Apparatus”, in a conventional RF source, the amount of ion energy reaching the surface of the object to be etched is This can be achieved by controlling the power of the RF wave, and the controllable range of the dissociation process in the plasma is narrow, and therefore the range of the controllable etching reaction on the surface of the target wafer is narrowly limited. In addition, since a magnetic field exists in the plasma generation chamber for high-density plasma, for example, there may be magnetohydrodynamic plasma instability due to drift waves generated in the plasma, which increases the ion temperature. This causes a problem that the direction of ion motion becomes non-uniform. Further problems include gate oxide degradation and etch profile deformation due to charge build up on the wafer.

  In a deposition technique known as atomic layer deposition (ALD), various gases are alternately injected into the chamber one after another for about 100 to 500 milliseconds. For example, a first gas is added into the chamber for about 500 milliseconds and the substrate is heated, and then the first gas (heating is optional) is turned off. Another gas is turned off after another 500 milliseconds (heating is optional) in the chamber. The next gas is turned off after being added for about 500 milliseconds (arbitrarily heated). This procedure is performed until all the gas is circulated in the chamber, and each gas procedure forms a highly conformal monolayer. Thus, ALD technology makes the gas injection and heating procedure pulses between 100 and 500 milliseconds. This approach requires high dissociation energy to break the bonds of various precursor gases such as silane and oxygen, and thus the substrate is heated to high temperatures, for example, 600 degrees Celsius for silane and oxygen processes. Heating to about 800 degrees is required.

  In one aspect, an apparatus for performing semiconductor processing includes a process chamber, a flash lamp adapted to be triggered repeatedly, and a controller connected to a control input of the flash lamp for triggering the flash lamp including.

  Implementations of the above aspects can include one or more of the following. The flash lamp can be pulsed to perform atomic layer processing including one or more of deposition, etching, epitaxial deposition, and sputter deposition. Output matching can be achieved using a solid state plasma generator with frequency tuning. The plasma generator can be a solid state generator with no moving parts and a short tuning response time. The solid state generator includes a switching power source, an amplifier connected to the power source, a reference frequency generator connected to the amplifier, a power measuring circuit for supplying feedback to the comparator and the reference frequency generator, and an output matching unit connected to the power measuring circuit. And a plasma excitation circuit connected to the output matching unit. Multiple precursor inlets can be coupled to the chamber, and the precursors from the precursor inlet react when the flash lamp is triggered. The controller can be computer controlled or can be a wired circuit. The controller turns on the flash lamp in the atomic layer process. The controller can perform atomic layer processing in the process chamber by circulating the flash lamp many times. The multilayer can be a plasma assisted layer and a non-plasma assisted layer.

In another aspect, a method of depositing a multilayer film on a semiconductor includes introducing a gas into a processing chamber and triggering a flash lamp to generate thermal energy in the chamber to deposit the layer.
Implementations of this aspect can include one or more of the following. The method includes purging the chamber and then sequentially sending a pulse of a flash lamp to each layer to be deposited.

  In yet another aspect, the multilayer semiconductor processing chamber is for reacting the processing gas with a gas source connected to the chamber for introducing the processing gas into a reaction chamber having a sample disposed therein. A high intensity flash lamp connected to the chamber and a controller connected to the flash lamp for triggering the flash lamp for each deposited layer.

  Implementations of the above aspects can include one or more of the following. A solid state RF plasma source can be used with the flash lamp, which is connected to the switching power supply, the RF amplifier connected to the power source, the reference frequency generator connected to the RF amplifier, the comparator and the reference frequency generator. A power measurement circuit for supplying feedback; an output matching unit connected to the power measurement circuit; and a plasma excitation circuit connected to the output matching unit. The controller triggers the flash lamp and / or pulses the solid state RF plasma source. The controller sequentially triggers the flash lamp and / or pulses the solid state RF plasma source for each layer to be deposited.

  Advantages of the system can include one or more of the following. The system can instantly deliver a significant amount of energy to the wafer surface to initiate the desired surface reaction. The system implements a combination of pulsed plasma and / or flash heating to thermally activate chemical precursors on the substrate surface at a temperature slightly lower than that required to initiate a sustained thermal reaction. Can be This technique can be used to make ultrathin layers of materials for atomic layer deposition processes. The system gives a well-controlled thickness. Customers can achieve the same result with thinner membranes and extend Moore's Law. The resulting high quality film has excellent properties such as high uniformity, controlled resistivity, high diffusion resistance, and high conformality, among others. Thus, the system allows for highly accurate etching, deposition or sputtering performance. Pulse modulation of the flash bulb and / or radio frequency operated plasma source allows tight control of radical production rate, ion temperature and charge accumulation in the plasma. In addition, the charge accumulation time in the wafer is on the order of milliseconds, and charge accumulation on the wafer is suppressed by pulse-modulated plasma on the order of microseconds, so this system suppresses damage to devices on the wafer caused by charge accumulation. And the suppression of notches that occur during the electrode etching process. The system allows the substrate to be heated to a relatively low temperature, typically below 400 degrees Celsius. Processing wafers at low temperatures can reduce thermal costs, especially reduce thermally induced mechanical strain and diffusional alloying of adjacent layers in the substrate and minimize grain growth It is useful to do.

  Other advantages can include one or more of the following. The system achieves excellent characteristics represented by high etch rate, high uniformity, high selectivity, high anisotropy, and low damage for semiconductor wafer etching, deposition or sputtering in compact substrate processing modules. High efficiency plasma work can be achieved. The system achieves a high density and highly uniform plasma operation at low pressure for etching the substrate and depositing a film on the substrate. In addition, the system has the ability to work with a wide variety of gases and gas mixtures, including highly reactive and corrosive gases.

  FIG. 1 shows an exemplary pulse processing system 100 having a processing chamber 102. The processing chamber 102 has a chamber body that encloses processing chamber components such as a chuck 103 that supports the substrate 105. The processing chamber typically maintains a vacuum and provides a sealed environment for process gases during substrate processing. Occasionally, the processing chamber needs to be regularly cleaned to clean the chamber and remove unwanted material that has accumulated in the chamber. As an aid to the processing chamber maintenance, a sufficiently large opening is usually provided at the top of the processing chamber to allow access to the internal parts of the processing chamber.

  The chamber 102 includes a plasma excitation circuit 106 driven by a solid plasma generator 110 and having a fast ignition function. One commercially available plasma source is the Litmas source available from LITMAS Worldwide, Matthews, NC. Generator 110 includes a switching power supply 112 connected to an alternating current (AC) line. The power source 112 rectifies the AC input and switches the AC input to drive the RF amplifier 116. The RF amplifier 116 operates at a reference frequency (eg, 13.56 MHz) supplied by the reference frequency generator 104. The RF amplifier 116 passes current through the power measurement circuit 118, which provides a feedback signal to the comparator 120 and the reference frequency generator 104. In this embodiment, power is measured only once and that information is used to control the gain of the RF amplifier 116 and, if necessary, to adjust the system. Next, the electric power is sent to the output matching unit 122, which directly drives the plasma excitation circuit 106. In one embodiment, the plasma excitation circuit 106 uses parallel plate electrodes in the chamber. However, other equivalent circuits including, for example, capacitance coupled or inductance coupled external electrodes can be used.

  Controller 130 generates periodic pulses and drives one input of frequency reference 104. The pulse effectively activates or deactivates the plasma generation. One embodiment of the controller 130 generates pulses at a frequency of 10 hertz (10 Hz) or lower. In another embodiment, the generated pulse has a pulse width of about 250 milliseconds and the pulse is repeated about every 50 milliseconds.

  Chamber 102 is controlled by controller 130 and includes one or more flash lamps 113 for heating the substrate. Various commercially available flash lamps can be used. In one embodiment, a xenon flash lamp (sphere or tube) is used to emit a large amount of spectral energy within a short pulse. Many suitable flash lamps known to those skilled in the art can be used. For example, Alex D., entitled “Design Considerations for Flash Lamp Triggering”. As discussed in McLeod's paper (Copyright 1998-2003 PerkinElmer, Inc.), power source energy is stored in a storage capacitor. When this energy is released and dissipated, a highly excited xenon plasma is created in the flash lamp. The emitted energy is much like sunlight and covers a wide spectral region from ultraviolet (UV) to infrared (IR). A charged energy storage capacitor is typically connected between the terminals of the two main electrodes (commonly referred to as the anode and cathode) of the flash lamp. The voltage at which this capacitor is charged is usually lower than the voltage that ionizes xenon.

  The process that causes the initial ionization is known as a trigger, which creates a voltage gradient (volts / inch) in the gas that is large enough to cause ionization. Most trigger mechanisms use trigger transformers to generate short duration high voltage pulses. Several different circuits have been developed to introduce this voltage to achieve ionization. Once ionization occurs, there is a conductive path through which the energy storage capacitor can be discharged, as evidenced by the narrow streamer between the main electrodes. As the level of ionization increases, the streamer increases in cross-sectional area and produces a strong flash.

  Many trigger methods can be used, including external injection, continuous injection, and pseudo continuous injection. These three triggering methods can be triggered by a simmer or pseudo-simmer mode circuit. The shimmer mode method requires that the flash lamp be triggered only once in a series of flashes. A separate power supply with specially designed load characteristics is used to allow current to flow continuously through the lamp in a low but stable ionization state. Depending on the type of flash lamp, typical simmer currents can range from 100 milliamps to several amperes. The voltage across the lamp is 100 to 150 volts. The main discharge energy obtained from a capacitor charged to a separate power source can now be switched into the lamp. Semiconductor switches such as SCR or gas or vacuum gaps can also be used. The gas in the lamp is more highly ionized and will flash when energy is dissipated. The gas will then be returned to the simmer state. Care must be taken in circuit design and layout so that transient currents due to parasitic elements do not cause deionization or that the semiconductor or insulator is not excessively distorted. The pseudo-simmer mode is a variation of a simmer mode circuit that combines a simmer power supply with a capacitor charging power supply. Operating conditions are limited by lamp and power load line considerations.

  In an external triggering embodiment, a high voltage trigger pulse is used to create a thin ionization streamer between the anode and cathode in the lamp. Ionization begins when the gas adjacent to the tube wall is excited by the voltage gradient created by this high voltage pulse from the trigger transformer. A thin nickel wire can be wrapped around the surface of a glass (or quartz) container (tube) to allow the glass to touch as long as possible between the inner tips of the electrodes. Connect one end of this line to the high voltage output (secondary winding) of the trigger transformer. The trigger voltage required to reliably trigger a particular flash lamp depends on the arc length, inner diameter, fill pressure, electrode material, and is usually given in the flash lamp characteristic data. Other factors such as ambient radiant energy and lamp aging characteristics also affect trigger requirements. The trigger pulse width is important in using this method because it requires a finite time for the ionization streamer to propagate through the flash lamp bore. It has been found that triggering is most reliable when the pulse width is at least 200 nanoseconds per inch of arc length.

  In another embodiment by the continuous injection trigger method, the discharge current from the energy storage capacitor is passed through the secondary winding of the trigger transformer. Therefore, the secondary winding of the trigger transformer must be designed to pass the full discharge current within the design limits of the ambient temperature. Here, the inductance of the secondary winding (of the trigger transformer) becomes part of the discharge circuit and can be used to control the current pulse waveform of the energy storage capacitor. Since the life of a flash lamp is inversely proportional to the peak current, it is desirable to design a critical damping circuit with this inductance optimized for damping. This will generate minimal peak current and prevent current reversal that can damage the flash lamp. This maximizes the life of the flash lamp for a specific energy requirement, where the power requirement determines the size of the trigger transformer. The pseudo continuous injection trigger method retains some of the advantages of the continuous injection trigger method without incurring some of its size, weight, and cost disadvantages. FIG. 5 shows four types of this circuit in various possible configurations of polarity and ground nodes. The trigger voltage is applied to the flash lamp as in the continuous injection method, but in this case the main energy discharge does not flow through the secondary winding of the trigger transformer. Instead, a path through an appropriate diode is provided.

  The pulse generator 130 also generates periodic pulses that drive the flash lamp 113. The pulse effectively activates or deactivates the plasma generation. One embodiment of the pulse generator 130 generates pulses at a frequency of 10 hertz (10 Hz) or less. In another embodiment, the generated pulse has a pulse width of about 50 milliseconds and the pulse is repeated every 5 seconds.

  The properties of the film deposited by the above method depend on the electron temperature in the plasma, the energy of ions incident on the substrate, and the ions and radicals generated in the vicinity of the ion sheath. The electron temperature distribution in the plasma, the type of each ion and radical produced in the plasma, and the ratio between the amount of ions and radicals modulate the high frequency voltage in the same way as described for plasma etching. Can be controlled. Therefore, if the deposition conditions for a film having excellent characteristics are known, the discharge plasma can be controlled with the modulation signal according to the present invention so as to satisfy this condition. In this way, processing characteristics relating to film deposition can be improved.

  FIG. 2 shows a flowchart of one exemplary semiconductor manufacturing process using the system 100 of FIG. Initially, a wafer is placed inside the chamber (step 200). Next, an appropriate processing gas is introduced into the chamber (step 202) and the controller 130 is periodically activated by a process activation switch to advance the desired process (step 204). The controller can operate one or more flash valves, one or more solid state RF heaters, or any combination of these two heat sources in any order. The particular type of process that is performed affects the selection of the process activation switch. The selection of the activation switch for any device manufacturing process can significantly affect the properties of the final semiconductor device, regardless of whether the process is a deposition process or an etching process. At the end of processing a layer of material, the gas in the chamber is purged (step 206) and the chamber is ready to take on further processing. Thus, for the next material layer, the appropriate processing gas is introduced into the chamber (step 208) and the controller 130 is periodically activated to proceed with the desired process (step 210). At the end of processing the second material layer, the gas in the chamber is purged (step 212), and the chamber is ready to accept another material layer. This process is repeated for each layer in the multilayer wafer.

  FIG. 3A shows one exemplary controller 300. The controller 300 includes a computer 302 that drives a digital to analog converter (DAC) 306. The DAC 306 generates a shaped waveform and is connected to a high voltage isolation unit 308 such as a power transistor or relay that drives the plasma generator 110. The controller 300 can generate various waveforms, such as a square wave and a sine wave, and can change the period and amplitude of the waveforms. Furthermore, in the above description, the RF power supplied to the plasma is modulated with a square wave. However, the modulation waveform is not limited to a rectangular wave. In other words, if the desired ion energy distribution, the desired electron temperature distribution, and the ratio between the desired ion amount and the desired radical amount are known, the modulation waveform is determined according to these factors. Using a rectangular wave as the modulation waveform has the advantage that the processing conditions can be easily set and the plasma processing can be easily controlled. It should be noted that since the square wave modulates the signal from the RF source in a discontinuous manner, the square wave can easily set the processing conditions as compared to the sine wave and its combined wave. Further, the pulse generator can also generate an amplitude modulated signal in addition to or in combination with the frequency modulated signal.

  FIG. 3B illustrates an exemplary embodiment using a timer chip, such as a 555 timer available from Signetics, Sunnyvale, California. The timer chip 555 is pre-configured to generate pulses at specific intervals with a suitable resistive capacitance (RC) network. The timer chip 555 generates a shaped waveform and is connected to a high voltage isolation unit 308 such as a power transistor or relay that drives the plasma generator 110 as described above.

  Referring now to FIG. 4, a multi-chamber semiconductor processing system 800 is shown. The processing system 800 has a plurality of chambers 802, 804, 806, 808 and 810 that are adapted to receive and process the wafer 842. Controllers 822, 824, 826, 828, and 830 control each of chambers 802, 804, 806, 808, and 810, respectively. Additionally, controller 821 controls another chamber, which is not shown for illustration purposes.

  Each of the chambers 802-810 provides a lid 104 for the chamber body 102. During maintenance operations, the lid 104 can be moved to the open position so that parts inside the chamber body 102 can be easily cared for and cleaned or replaced when needed.

  Chambers 802-810 are connected to a transfer chamber 840 that contains a wafer 842. Wafer 842 is placed at the tip of a robot blade or arm 846. Robot blade 846 receives wafer 842 from outside the processing area.

  Movement of the wafer 842 between processing areas involves passing the wafer through one or more doors separating the areas. The door may be a load lock chamber 860-862 for passing a wafer containment container or wafer boat capable of holding about 25 wafers in one embodiment. Wafer 842 can be moved through the chamber from one area to another within the container. The load lock can also include an air circulation and filtration system that effectively flushes ambient air around the wafer.

  Each load lock chamber 860 or 862 is disposed between the sealed openings 850 or 852 and has the function of moving the semiconductor wafer between manufacturing regions. The load lock 860-862 can include an air circulation and filtration system that effectively flushes ambient air around the wafer. Each load lock chamber 860 or 862 can also be purged during a wafer transfer operation, significantly reducing the number of contaminants in the air that are moved from one manufacturing area to another. The load lock chamber 860-862 may also include pressure sensors 870-872 that measure air pressure for control.

  During operation, the wafer cassette or wafer boat is loaded into the load lock through a load lock door at an opening 850-852 in the front of the system. The door is closed, the system is evacuated, and the ultimate pressure is measured by pressure sensors 870-872. A slit valve (not shown) is opened to allow the wafer to move from the load lock to the transfer chamber. A robot blade captures the wafer and delivers the wafer to the appropriate chamber. A second slit valve opens between the transfer chamber and the process chamber and the wafer is carried into the process chamber.

  Thus, the containers remain in their respective manufacturing areas during the wafer transfer operation, and any contaminants attached to the container do not move from one manufacturing area to another with the wafer. Furthermore, since the air in the transfer chamber can be purged during the wafer transfer operation, the number of contaminants in the air moving from one manufacturing area to another manufacturing area is significantly reduced. Thus, during operation, the transfer chamber provides a high level of separation during the manufacturing process.

  FIG. 5 shows an exemplary apparatus 40 for liquid and gas precursor delivery using the system 100 or system 300. The apparatus 40 includes a chamber 44, such as a CVD chamber. The chamber 40 includes a chamber body that defines an evacuable sealed area for performing substrate processing. The chamber body has a plurality of ports including at least a substrate inlet port that is selectively sealed by a slit valve and a side port through which the substrate support member can be moved. The apparatus 40 also includes a gas precursor injector 46 connected to the chamber 44 and a liquid precursor injector 42 connected to the chamber 40.

  In the liquid precursor injector 42, the precursor 60 is placed in a sealed container 61. An inert gas 62 such as argon is injected into the container 61 through the tube 63 to raise the pressure inside the container 61 and cause the copper precursor 60 to flow through the tube 64 when the valve 65 is opened. The liquid precursor 60 is measured by the liquid flow controller 66 and flows into the tube 67 and into the vaporizer 68 attached to the CVD chamber 71. The vaporizer 68 heats the liquid to vaporize the precursor 60 into a gas 69 and flows over the substrate 70, which is heated to an appropriate temperature by the susceptor to decompose the copper precursor, A copper layer is deposited on the substrate. The CVD chamber 71 is sealed from the surroundings by exhaust pumping 72, allowing deposition to occur in a controlled partial vacuum.

  In the gas precursor injector 46, a liquid precursor 88 is contained within a sealed container 89 that is enclosed by a temperature control jacket 100 and allows the temperature of the precursor to be controlled within 0.1 degrees Celsius. A thermocouple (not shown) is submerged in the precursor 88, an electronic control circuit (not shown) controls the temperature of the jacket 100, and the jacket 100 controls the temperature of the liquid precursor to control the precursor vapor. Control the pressure. The liquid precursor can be heated or cooled to produce the appropriate vapor pressure required for a particular deposition process. The carrier gas 80 can flow through the gas flow controller 82 when the valve 83 and only one of the valves 92 or 95 are opened. Also shown is one or more additional gas flow controllers 86, which can flow additional gas 84 when valve 87 is opened, if desired. Additional gas 97 can also be injected into the vaporizer 68 through an injection tube connected to a valve 79 attached to the gas flow controller 99. Depending on the vapor pressure, a certain amount of precursor 88 will be carried by the carrier gases 80 and 84 and will be exhausted through the tube 93 when the valve 92 is open.

  After the substrate is placed inside the CVD chamber 71, the substrate is heated by the heater 100 or 300 as described above. After the substrate reaches the proper temperature, valve 92 is closed and valve 95 is opened to allow carrier gases 80 and 84 and precursor vapor to enter vaporizer 68 through connecting tube 96. Such a valve arrangement prevents the sudden entry of steam into the chamber 71. The precursor 88 is already vapor, and the vaporizer is used only as a showerhead to uniformly distribute the precursor vapor on the substrate 70. After a predetermined time, which depends on the copper deposition rate and the thickness required for initial copper deposition, valve 95 is closed and valve 92 is opened. The flow rate of the carrier gas can be accurately controlled to as little as 1 sccm per second, and the vapor pressure of the precursor can be reduced to a fraction of one atmosphere by cooling the precursor 88. Such an arrangement allows the copper deposition rate to be accurately controlled to values less than 10 angstroms per minute, if desired. Once the initial copper layer has been deposited, the liquid source delivery system can be activated to allow subsequent deposition to proceed more quickly.

  6A and 6B show two operating conditions of an embodiment 600 that performs barrier pulsed plasma atomic layer deposition. FIG. 6A shows the embodiment 600 in one deposition condition, and FIG. 6B shows the embodiment 600 in another deposition condition. Referring to FIGS. 6A and 6B, the chamber 602 receives gas through one or more gas inlets 604. A solid state plasma generator 605 is attached to the top of the chamber 602 and one or more plasma excitation coils 607 are located near the gas inlet 604. A flash valve 611 is disposed above the substrate 610. The liquid precursor system 606 introduces precursor gas through the vaporizer 608 and into the chamber 602 by the precursor spray ring 630.

  The chuck 608 supports the substrate 610 so as to be movable. In FIG. 6A, chuck 608 and substrate 610 are lifted and ready for deposition. The substrate 610 is disposed in the chamber. An appropriate processing gas is introduced into the chamber through the inlet 604, and a pulsed plasma controller 605 is periodically activated by a process activation switch to advance the desired process. The particular process that is performed affects the selection of the process activation switch. The selection of the activation switch for any device manufacturing process can significantly affect the properties of the final semiconductor device, regardless of whether the process is a deposition process or an etching process. At the end of processing of one material layer, the gas in chamber 602 is purged and chamber 602 is ready to accept further processing. This process is repeated for each layer on the multilayer wafer. At the end of the deposition of all layers, the chuck 608 is lowered and the substrate 610 can be removed through the opening 611.

  The system allows the substrate to have temperature uniformity with reliable real-time multipoint temperature measurement in closed loop temperature control. The control portion is implemented in a computer program executed on a programmable computer having a processor, a data storage system, volatile and non-volatile memory and / or storage elements, at least one input device and at least one output device. The

  Each computer program is tangibly stored in a machine-readable storage medium or device readable by a general purpose or special purpose programmable computer (eg, program memory 522 or magnetic disk), and the storage medium or device is read by the computer. Sometimes configure and control the operation of the computer to execute the processes described internally. The present invention can also be thought of as embodied in a computer readable storage medium configured by a computer program, in which case the storage medium configured as such is a function described herein. The computer is operated in a specific and predetermined way to implement

  In CVD (chemical vapor deposition), a gas or vapor mixture is flowed over a hot wafer surface. The reaction then takes place on the hot surface, where deposition takes place. The basic feature of the CVD process is the interaction of all precursor vapors on the substrate or the decomposition of the precursor on the substrate surface. In many cases, the reaction requires the presence of an energy source such as thermal energy (in the form of a resistively heated substrate or radiant heating) or plasma energy (in the form of plasma excitation).

  ALD is another deposition technique. In ALD, various vapors are alternately injected into the chamber in a separate order. For example, the first precursor vapor is delivered into the chamber and adsorbed on the substrate. A second precursor vapor is then delivered into the chamber and reacts with the molecules adsorbed on the substrate to form the desired film. This sequence is repeated many times until the deposited film reaches the desired thickness. Although there are many variations of the ALD process, all of the ALD processes have two common characteristics: the precursor vapor flows sequentially to react the precursor with the substrate surface, and the thickness per cycle is self-limiting. Share that.

  One fundamental difference between CVD and ALD is the reaction characteristics. In CVD, the precursors react (or decompose) with each other on the substrate surface, while in ALD, the precursors react with the substrate surface and the precursors do not react with each other.

  Another fundamental difference between CVD and ALD is the self-limiting characteristic that defines the deposition thickness over time. CVD cannot be self-limiting because the reaction occurs at the surface between the precursors and thus continues to occur as long as the precursor is present and the deposition thickness increases with deposition time. In contrast, the maximum thickness per cycle of the ALD process is one monolayer due to the self-limiting property that the substrate surface saturates with the first precursor. The first precursor can be adsorbed on the substrate, or the first precursor can cause some reaction in the substrate, but the first precursor also saturates the substrate surface, and the surface is the first precursor. Terminated with a ligand. A co-pending US patent application Ser. No. 10 / 360,135 entitled “Nanolayer Deposition Process” filed Feb. 4, 2003 and published as US 2004-0151845 on Aug. 5, 2004 is disclosed. Which is incorporated herein by reference.

The present invention discloses a method of sequentially depositing a thin film on a substrate, the method comprising:
A thin film is deposited by CVD,
Processing the thin film to modify the properties of the thin film,
Includes steps.
These two steps can be accomplished by precursor flow. These two steps can be repeated until the desired thickness is achieved.

  The deposition step in the present invention is a CVD deposition step, which means that the precursors react with each other or decompose at the substrate surface. In addition, this deposition process allows non-self-limiting growth and is a function of substrate temperature and process time. It is possible to put a pump or purge step between the above two steps. In a process variation, the deposition step can be any non-self limiting deposition step.

  The processing step changes the properties of the already deposited film. The processing step can process the deposited film by changing the film composition, doping the deposited film, or removing impurities from the deposited film. The processing step can also deposit another layer on the deposited film to alter the properties of the deposited film. For example, an additional layer can react with an existing layer to form a synthetic layer, or a nanolaminate film can be formed with minimal reaction. The treatment step can be a temperature treatment such as plasma treatment or rapid heat treatment by lamp heating.

  The steps in the present invention are any CVD deposition steps such as thermally activated CVD, plasma enhanced CVD using parallel plate plasma, inductively coupled plasma (ICP), microwave plasma, remote plasma, or rapid thermal processing using lamp heating. be able to. In addition to making this deposition step a deposition step, the processing step can also change the properties of the deposited film as a CVD deposition step.

  One advantage of the present invention is the non-self-limiting nature of the first deposition step, allowing the deposition step thickness to be adjusted to achieve a greater thickness per cycle. Thus, the thickness per cycle in the present invention is a function of process temperature and process time. In contrast, the ALD method is based on the saturation of the ligand on the substrate surface and hence the thickness per cycle is fixed and cannot be changed.

  It should be understood that the above embodiments represent a few of the practically endless applications of plasma processing techniques embodied within the scope of the present invention. Furthermore, although the invention has been described with reference to the specific embodiments above, this description should not be construed in a limiting sense. For example, the operating time rate, cycle time, and other parameters / conditions can be varied to obtain the desired characteristics of the wafer.

  Various modifications of the disclosed embodiments, and alternative embodiments of the invention will be apparent to those skilled in the art upon reference to the above description. However, the invention is not limited to the illustrated and described embodiments. For example, the radiation source can be a radio frequency heater rather than a lamp. Therefore, the scope of the present invention is defined by the appended claims. Furthermore, the appended claims are intended to cover such modifications as fall within the true scope of the present invention.

1 illustrates an exemplary pulse processing system having a processing chamber. 2 shows a flowchart of one exemplary semiconductor manufacturing process using the system of FIG. 3 illustrates an exemplary pulse generator embodiment. 3 illustrates an exemplary pulse generator embodiment. 1 shows a multi-chamber semiconductor processing system. An exemplary apparatus for liquid and gas precursor delivery. Fig. 2 shows the operating conditions of an embodiment for performing a barrier pulsed plasma atomic layer deposition. Fig. 2 shows the operating conditions of an embodiment for performing a barrier pulsed plasma atomic layer deposition.

Claims (40)

A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a non-self-limiting deposition process in which the deposition thickness increases with deposition time;
(B) whether to trigger a flash lamp that generates thermal energy to change the deposited layer, or to trigger a plasma source to generate plasma energy to change the deposited layer Trigger a flash lamp that generates thermal energy and trigger a plasma source that generates plasma energy to change the deposited layer;
Steps,
A method comprising the steps of: After step (a)
The method of claim 1, further comprising (a1) purging the first precursor (a1).   The method of claim 1, wherein step (b) further comprises introducing a second precursor. After step (b)
4. The method of claim 3, further comprising (b1) purging the second precursor (b1).   The method of claim 1, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   The method of claim 2, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   The method according to claim 4, further comprising a plurality of the steps (a) to (b1) until a desired film thickness is achieved.   The method of claim 1, wherein step (a) includes using plasma energy in a deposition process.   The method of claim 1, wherein the first plurality of precursors in step (a) comprises a CVD precursor. Said second precursor in the step (b), and wherein the nitrogen, oxygen, hydrogen, ammonia, NF _3, silane, ozone, to include process gases selected from the group consisting of argon, claim 3 The method described in 1.   The method of claim 3, wherein the second precursor in step (b) comprises a CVD precursor. A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a non-self-limiting deposition process in which the deposition thickness increases with deposition time;
(B) triggering a flash lamp that generates thermal energy to alter the deposited film;
A method comprising steps. After step (a)
The method of claim 12, further comprising the step of (a1) introducing and purging a first precursor (a1). Said step (b) further comprises introducing a second precursor;
After step (b)
(B1) further comprising the step (b1) of purging the second precursor;
The method according to claim 13, wherein:   13. The method of claim 12, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved. A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a non-self-limiting deposition process in which the deposition thickness increases with deposition time;
(B) triggering a plasma source that generates plasma energy to alter the deposited film;
A method comprising steps. After step (a)
The method of claim 16, further comprising the step of (a1) introducing and purging a first precursor (a1). Said step (b) further comprises introducing a second precursor;
After step (b)
(B1) further comprising the step (b1) of purging the second precursor;
The method according to claim 17, wherein:   The method of claim 16, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   The method of claim 16, wherein step (a) includes using plasma energy in the deposition process. A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a deposition process in which a thin film is produced by reaction between precursors on the substrate surface or decomposition of the precursor;
(B) whether to trigger a flash lamp that generates thermal energy to change the deposited layer, or to trigger a plasma source to generate plasma energy to change the deposited layer Trigger a flash lamp that generates thermal energy and trigger a plasma source that generates plasma energy to change the deposited layer;
Steps,
A method comprising the steps of: After step (a)
The method of claim 21, further comprising (a1) purging the first precursor (a1).   The method of claim 21, wherein step (b) further comprises introducing a second precursor. After step (b)
24. The method of claim 23, further comprising (b1) purging the second precursor (b1).   The method of claim 21, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   23. The method of claim 22, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   The method according to claim 24, further comprising a plurality of the steps (a) to (b1) until a desired film thickness is achieved.   The method of claim 21, wherein step (a) includes using plasma energy in the deposition process.   The method of claim 21, wherein the first plurality of precursors in step (a) comprises a CVD precursor. Said second precursor in the step (b), and wherein the nitrogen, oxygen, hydrogen, ammonia, NF _3, silane, ozone, to include process gases selected from the group consisting of argon, claim 23 The method described in 1.   24. The method of claim 23, wherein the second precursor in step (b) comprises a CVD precursor. A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a deposition process in which a thin film is produced by reaction between precursors on the substrate surface or decomposition of the precursor;
(B) triggering a flash lamp that generates thermal energy to alter the deposited film;
A method comprising steps. After step (a)
33. The method of claim 32, further comprising the step of (a1) introducing and purging a first precursor. Said step (b) further comprises introducing a second precursor;
After step (b)
(B1) further comprising the step (b1) of purging the second precursor;
34. The method of claim 33, wherein:   35. The method of claim 32, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved. A method of depositing a film in a processing chamber comprising:
(A) introducing a first precursor to deposit a thin layer by a deposition process in which a thin film is produced by reaction between precursors on the substrate surface or decomposition of the precursor;
(B) triggering a plasma source that generates thermal energy to alter the deposited film;
A method comprising steps. After step (a)
37. The method of claim 36, further comprising (a1) introducing and purging a first precursor (a1). Said step (b) further comprises introducing a second precursor;
After step (b)
(B1) further comprising the step (b1) of purging the second precursor;
38. The method of claim 37, wherein:   The method of claim 36, further comprising a plurality of the steps (a) and (b) until a desired film thickness is achieved.   38. The method of claim 36, wherein step (a) includes using plasma energy in the deposition process.

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