TW201306125A - Post-ash sidewall healing - Google Patents

Abstract

Methods of decreasing the effective dielectric constant present between two conducting components of an integrated circuit are described. The methods involve the use of a gas phase etch which is selective towards the oxygen-rich portion of the low-K dielectric layer. The etch rate attenuates as the etch process passes through the relatively high-K oxygen-rich portion and reaches the low-K portion. The etch process may be easily timed since the gas phase etch process does not readily remove the desirable low-K portion.

Description

Ashing rear sidewall repair

This case relates to a method of manufacturing a semiconductor electronic device.

Integrated circuit fabrication methods have reached the point where hundreds of millions of transistors are typically formed on a single wafer. Each new generation of manufacturing technology and equipment is enabling commercial scale production of smaller and faster transistors, but it also increases the difficulty of making smaller and faster circuit components. The shrinking of circuit component size (now completely below the 50 nm threshold) has led wafer designers to look for new low-resistance conductive materials and new low-k dielectric (ie, low-K) insulating materials to enhance (or simply maintain The electrical performance of the integrated circuit.

As the number of transistors in each region increases, the parasitic capacitance becomes a significant obstacle to the transistor switching rate. Capacitance is present between all adjacent electrically insulated conductors in the integrated circuit, and the capacitance limits the switching rate regardless of whether the conductive portion is at the "front end" or "back end" of the manufacturing process.

Thus, new technologies and materials are needed to form low K materials between adjacent conductors. One class of materials for providing a low K separation between the conductors are oxidized organosilane films, such as Black Diamond ^TM film, (Applied Materials from Santa Clara, California City, Applied Materials Black Diamond ^TM film on such market , Inc.) obtained. The films have a lower dielectric constant (e.g., about 3.5 or less) than typical spacer materials such as tantalum oxides and nitrides. Unfortunately, some new processes involve exposing low K films to environments that may increase the effective dielectric constant, limiting device performance.

Thus, there is a need for new processes that maintain a low effective dielectric constant after exposure of the low K film to such environments.

The present invention describes a method for reducing the effective dielectric constant present between two conductive components of an integrated circuit. The methods involve the use of a vapor phase etch that is selective for the oxygen-rich portion of the low-k dielectric layer. When the etching process passes through the relatively high K oxygen-rich portion to the low K portion, the etching rate is weakened. Since the vapor phase etching process does not easily remove the required low K portion, it is easy to time control the etching process.

Embodiments of the invention include a method of reducing the effective dielectric constant of a low K dielectric material between two trenches on a patterned substrate in a substrate processing region. The low K dielectric material forms the walls of the two trenches. The method includes the step of transferring the patterned substrate into the substrate processing region. The method further includes the step of vapor phase etching the patterned substrate to reduce an average dielectric constant of the low K dielectric material by removing an outer dielectric layer from the low K dielectric material.

Other embodiments and features of the present invention will be set forth in part in the description. The features and advantages of the disclosed embodiments can be realized and attained by the <RTIgt;

The present invention describes a method for reducing the effective dielectric constant present between two conductive components of an integrated circuit. The methods involve the use of a vapor phase etch that is selective for the oxygen-rich portion of the low-k dielectric layer. As the etch process passes through the relatively high K oxygen-rich portion to the low K portion, the etch rate decreases. Since the vapor phase etching process does not easily remove the desired low K portion, it is easy to time control the etching process. Vapor phase etching is superior to liquid buffered oxide etching and is particularly suitable for processing patterned substrates. Vapor etchants are easier to remove from narrow structures than liquid etchants.

Embodiments of the present invention are directed to a method of etching a low K material on a patterned substrate to increase the effective dielectric constant, thereby improving device performance. An exemplary process flow that can benefit from the methods provided herein involves transferring two different lithographic-etching patterns to a substrate. The processes can be designed to pattern the substrate twice to achieve the desired steps in the via structure, rather than the generally vias having opposing vertical walls. Such process sequences may require the use of a photoresist to coat the patterned substrate such that the photoresist penetrates vias and other gaps in the low K material. Removal of the photoresist generally involves ashing, i.e., exposing the structure to an oxidizing precursor. While removing the gap-filled photoresist, the ashing step also changes the sidewalls of the gap in a manner that increases the dielectric constant in the thin outer layer of the low-K material. Some ashing involves exposure to oxygenates that are excited in the plasma. In such cases, the oxygen treatment oxidizes the surface of the low K material and the oxygen treatment increases the oxygen content relative to the carbon content. In order to return the dielectric constant to the level before the ashing of the low K material, the method proposed herein removes the relatively thin, relatively high K material of this layer.

For a better understanding and understanding of the present invention, reference is now made to Figs. 1-2, which are cross-sectional views of a gap during processing and a flowchart for processing such gaps, in accordance with the disclosed embodiments. The structure shown in FIG. 1A is produced by a photolithography-etch-lithography-etch sequence in which a second photolithography-etching step is performed on the low dielectric constant material 110. Open a wider groove in -1. The second etch only penetrates a portion of the via that reaches the bottom of the trench leaving a step in the low K material 110-1. Above and below the step are substantially vertical walls formed of a low K material. In the disclosed embodiment, the walls may be offset from the theoretical vertical lines shown in Figures 1A-1B, but the walls may be within 10, 5 or 2 degrees from vertical. After the second etch, some of the photoresist 120 remains at the bottom of the trench, and the photoresist 120 needs to be removed before the gap fills the metal. When the patterned substrate is transferred to the processing chamber (operation 210), the process of removing the residual photoresist 120 begins. An oxygen-radical gas stream is introduced into the ashing chamber (operation 215) and the photoresist is removed from the trench. In the example illustrated in FIG. 1A, a lanthanum carbide niobium (SiCN) layer 125-1 is included to protect the low K material 110-1 from metal diffusion from the underlying material. The SiCN layer 125-1 may also be modified via an oxy group to remove a portion of the SiCN at the bottom of the trench to obtain a patterned SiCN layer 125-2. Exemplary SiCN layer is Blok ^TM, the Blok ^TM available from the city of Santa Clara, California, Applied Materials. In some embodiments there is a SiCN layer, while in other embodiments there is no SiCN layer. The oxygen gas stream also oxidizes the walls of the low K material 110, which undesirably increases the dielectric constant near the surface (the walls of the trench). Exemplary low K material is a silicon oxide carbon (SiOC), and exemplary SiOC same product available from Applied Materials Black Diamond ^TM. Ignoring the formation of an oxygen-rich (relatively high K) surface layer and continuing to fill the gap with the metal deposition trench will limit the operational regime of the final device.

Using the following steps, the low K material 110 with reduced dielectric constant can be restored to almost the level before the ashing of the low K material 110. The patterned substrate is transferred to a substrate etched region of the processing chamber for further processing (operational step 220). A stream of ammonia and nitrogen trifluoride is introduced into the plasma zone separated from the treatment zone (operation 222). The separated plasma region may be referred to herein as a remote plasma region, and the separated plasma region may be a different module than the processing chamber or a compartment within the processing chamber. The remote plasma effluent (product of the remote plasma) flows into the processing chamber and reacts with the surface of the substrate (operation 225). A gas stream of plasma effluent reacts with the surface to produce a solid residue comprising material from the plasma effluent and material from the wall of the reacting low K material 110. In an exemplary apparatus section, a detailed chemical reaction that facilitates understanding of the process will be provided. The solid residue is then removed by heating the patterned substrate above the sublimation point of the solid residue (operation 240). The process is completed by removing the patterned substrate from the substrate etched region (operation 245), and the final structure is illustrated in FIG. 1B.

The etch rate of the outer dielectric layer is greater than the etch rate of the relatively lower K dielectric material inside the outer dielectric layer. In an embodiment of the invention, the vapor phase etch rate of the outer dielectric layer exceeds the etch rate of the remaining low K dielectric material by more than a multiple of 25, 50 or 100. In an embodiment, the thickness of the outer dielectric layer is approximately 150 Or smaller, about 100 Or smaller, or about 50 Or smaller.

Exemplary process just described is part of a series SiConi ^TM etching, the etching SiConi ^TM series generally relates to the presence of fluorine-containing gas stream prior to the hydrogen-containing precursor and the body simultaneously. In various embodiments, the fluorine-containing precursor comprises nitrogen trifluoride, hydrogen fluoride, diatomic fluorine, monoatomic fluorine, and fluorine-substituted hydrocarbons or a combination of the foregoing. In various embodiments, the hydrogen-containing precursor comprises atomic hydrogen, diatomic hydrogen, ammonia, hydrocarbons, hydrocarbons that are not completely substituted by halogen, or a combination of the foregoing. For simplicity, the discussion herein may contain some of the exemplary reference SiConi ^TM etching, the exemplary SiConi ^TM etching using a combination of ammonia and nitrogen trifluoride. Etching may be used instead of any SiConi ^TM depicted in Figure 2 and illustrated in the exemplary etching. All SiConiTM etches containing fluorine and hydrogen (but substantially no or no oxygen at all ⁾ exhibit a strong selectivity for etching yttrium oxide. These etching processes remove germanium, polysilicon and tantalum carbon oxide very slowly. As a result, SiConi ^(TM) has the additional advantage of leaving the desired carbon ruthenium low K material 110 substantially perfectly, even after etching is continued from the ruthenium oxide on the wall of the low K material 110. This selectivity allows the process to be timed without any other form of endpoint determination.

Although the examples described herein relate to double patterning (LELE) of low K dielectric layers, other process flows that require deposition of photoresist in the gaps in the low K layer are also possible. As a result, the methods proposed and claimed are effective in any application involving ashing any gap fill material that can be removed by oxidation treatment. The ashable gap fill material includes a bottom or top anti-reflective coating (BARC or TARC) as well as various photoresists and other similar carbonaceous materials. In the disclosed embodiment, the ashable gap fill material is substantially devoid of oxygen. Oxidation treatment removes the ashable gap fill material but undesirably modifies the walls, increasing the dielectric constant in the modified surface layer. The increased dielectric constant can be reduced using the methods described herein. The shape of the trench may include a stepped structure on the trench walls as shown in Figures 1A-1B, but in other disclosed embodiments there are substantially no steps.

As previously described, the gaps and trenches are formed in the low K material. The exemplary gap has a step between two approximately vertical walls of the low K material (see Figure 1). In other embodiments, no steps are formed in the low K material, and only a single approximately vertical wall is formed in the low K material. In the disclosed embodiment, the single vertical wall may be within 10, 5 or 2 degrees from vertical. In the disclosed embodiments, the low K material may have a dielectric constant less than 3.9, 3.7, 3.5, 3.3, or 3.1 prior to ashing (or after the treatments presented herein). The dielectric constant is largely determined by the concentration of carbon in the lower K layer of the cerium oxide. According to an embodiment of the present invention, after ashing, the external dielectric layer may have a dielectric constant greater than 3.0, greater than 3.2, or greater than 3.5, while the remaining low-k dielectric materials have dielectric constants less than 3.0, less than 3.2, or less than 3.5, respectively. .

An optional step can be used after vapor phase etching. The vapor phase etch just described may leave a post-etch residue containing a portion of the vapor phase etchant. The presence of residues after etching may be related to electrical leakage between adjacent wires. This leakage can be caused, for example, by a fluorine-containing post-etch residue. Thus, the etched substrate can then be treated with a plasma effluent to remove some of the post-etch residue and mitigate any electrical leakage that may be present from the inclusion of Ar, N ₂ , NH ₃ and H _{2 .} One or more plasmas.

During operation 215, the gap-filled photoresist 120 is removed using an oxy group. The oxy group is typically formed in the distal plasma region and flows to the substrate etched region. In some embodiments, the group comprises a neutral substance, such materials include neutral oxygen atoms (O) and ozone (O ₃₎ of one or more. Some ionized species may be present in the etched regions, however, the ionized species tends to recombine more rapidly than unionized (neutral) atomic oxygen and unionized ozone. In some embodiments, the remote plasma is more preferred than the plasma in the etched region to ensure that the ionized species has sufficient chance of neutralization. In the disclosed embodiment, the opening and path length from the distal plasma to the etched region is preferably selected to cause neutral atomic oxygen (O) to travel to the substrate etched region. In some embodiments, in order to sidewall passivation to reduce oxidation, SiF ₄ group simultaneously with (using a remote plasma or a plasma etch region) flow together. The oxidized regions of the low K material may still appear and the oxidized regions of the low K material may exhibit an increased dielectric constant. Thus, structures formed in this manner can still benefit from the methods disclosed herein.

It describes the isolation chamber for SiConi ^TM etching and ashing above. In an alternate embodiment, the processes are performed in the same chamber in the order of the processing steps without having to remove the patterned substrate from the processing chamber.

Additional vapor phase etch processing parameters and processing details are disclosed during the description of an exemplary processing system.

Exemplary processing system

FIG. 3 is a partial cross-sectional view illustrating an illustrative processing chamber 300 in which embodiments of the present invention may be performed. In general, ammonia and nitrogen trifluoride can be introduced into the distal plasma regions 361-363 via one or more openings 351 and excited by the plasma power source 346.

In one embodiment, the processing chamber 300 includes a chamber body 312, a lid assembly 302, and a support assembly 310. A lid assembly 302 is disposed at an upper end of the chamber body 312, and the support assembly 310 is at least partially disposed within the chamber body 312. Processing chamber 300 and associated hardware are preferably formed from one or more process compatible materials (e.g., aluminum, stainless steel, etc.).

The chamber body 312 includes a slit valve opening 360 formed in a sidewall of the chamber body 312 for providing access to the interior of the processing chamber 300. The slit valve opening 360 is selectively opened and closed via a wafer processing robot (not shown) to allow access to the interior of the chamber body 312. In one embodiment, the wafers may be transported into or out of the process chamber 300 via the slit valve opening 360 to an adjacent transfer chamber and/or load lock chamber, or other chamber within the cluster tool. An exemplary clustering tool that can include the processing chamber 300 is illustrated in FIG.

In one or more embodiments, the chamber body 312 includes a chamber body passage 313 for flowing a heat transfer fluid through the chamber body 312. The heat transfer fluid can be a heating fluid or a coolant, and the heat transfer fluid is used to control the temperature of the chamber body 312 during process and substrate transfer. The temperature of the chamber body 312 is important to prevent undesired accumulation of gases or by-products on the walls of the chamber. Exemplary heat transfer fluids include water, ethylene glycol, or a mixture of the two. An exemplary thermal transfer fluid can also include nitrogen. The support assembly 310 can have a support assembly channel 304 for flowing a heat transfer fluid through the support assembly 310, thereby affecting the substrate temperature.

The chamber body 312 can further include a bushing 333 that surrounds the support assembly 310. Bushing 333 is preferably removable for servicing and cleaning. The bushing 333 may be made of a metal such as aluminum, or a ceramic material. However, the bushing 333 can be any process compatible material. The bushing 333 may be bead blasted to increase the adhesion of any material deposited on the bushing 333, thereby preventing the material from falling off, which causes the process chamber 300 to become contaminated. In one or more embodiments, the bushing 333 includes one or more openings 335 formed in the bushing 333 and a pump passage 329 that is in fluid communication with the vacuum system. The opening 335 provides a flow path for the gas to enter the pump passage 329, thus providing an outlet for the gas within the process chamber 300.

The vacuum system can include a vacuum pump 325 and a throttle valve 327 to regulate the flow of gas through the process chamber 300. The vacuum pump 325 is coupled to the vacuum crucible 331 provided on the chamber main body 312, and thus is in fluid communication with the pump passage 329 formed in the bushing 333. The terms "gas" and "multiple gases" are used interchangeably and, unless otherwise indicated, the above terms mean one or more reactants, catalysts, carriers, scavengers, cleaning agents, combinations of the foregoing, and any other introduced treatments. The fluid within chamber 312. The term "precursor" is used to refer to any process gas that participates in a reaction to remove or deposit material from a surface.

The opening 335 enables the pump passage 329 to be in fluid communication with the treatment region 340 within the chamber body 312. The treatment region 340 is defined by the lower surface of the lid assembly 302 and the upper surface of the support assembly 310, and the treatment region 340 is surrounded by the liner 333. The openings 335 can be of uniform size and the openings 335 can be evenly spaced around the liner 333. However, any number, location, size or shape of openings may be used, each of which may vary depending on the desired flow pattern of gas on the substrate receiving surface, as discussed in more detail below. Moreover, the size, number, and location of the openings 335 are configured to achieve a uniform flow of gas exiting the process chamber 300. Additionally, the opening size and position can be configured to provide a fast or high volume pumping action to facilitate rapid venting of gas from the processing chamber 300. For example, the number and size of the openings 335 that are in close proximity to the vacuum crucible 331 can be smaller than the number and size of the openings 335 that are disposed away from the vacuum crucible 331.

A gas supply panel (not shown) is typically used to provide process gas to the process chamber 300 via one or more openings 351. The particular gas or gases used may depend on the process or processes being performed within the process chamber 300. Illustrative gases can include, but are not limited to, one or more precursors, reducing agents, catalysts, carriers, scavengers, cleaning agents, or any mixture or combination of the foregoing. Typically, one or more gases introduced into the process chamber 300 flow into the plasma space 361 via openings 351 in the top plate 350. Alternatively or in combination, the process gas may be introduced into the processing region 340 more directly via the opening 352. The opening 352 avoids remote plasma excitation and is useful for processes involving gases that do not require plasma excitation or processes that do not benefit from additional gas excitation. Active oxygen generated in the remote plasma can be introduced into the treatment zone 340 via the opening without passing through the zones 361, 362, and 363. Electrically operated valves and/or flow control mechanisms (not shown) may be used to control the flow of gas from the gas supply to the process chamber 300. Depending on the process, any of a variety of gases can be delivered to the processing chamber 300 and can be mixed in the processing chamber or before the gases are delivered to the processing chamber 300.

The lid assembly 302 can further include an electrode 345 that produces a plasma of active species within the lid assembly 302. In one embodiment, electrode 345 is supported by top plate 350 and electrode 345 is electrically insulated from top plate 350 by insertion of an electrically insulating ring 347 made of alumina or any other insulating and process compatible material. In one or more embodiments, electrode 345 is coupled to power source 346 and the remaining cover assembly 302 is coupled to ground. Thus, a plasma of one or more process gases can be generated in the remote plasma region, the remote plasma region being comprised of spaces 361, 362 and/or 363, the spaces 361, 362 and/or 363 being at the electrodes 345 is between the annular mounting flange 322. In an embodiment, the annular mounting flange includes or an annular mounting flange to support the gas delivery plate 320. For example, plasma can be introduced and held between electrode 345 and one or both of the blockers of blocker assembly 330. Alternatively, in the absence of the blocker assembly 330, a plasma can be created and contained between the electrode 345 and the gas delivery plate 320. In either embodiment, the plasma is completely confined or contained within the lid assembly 302. Accordingly, since there is no active plasma in direct contact with the substrate, the plasma is a "distal plasma" which is disposed within the chamber body 312. As a result, since the plasma is separated from the surface of the substrate, damage of the substrate by the plasma can be avoided.

Various power sources 346 can excite ammonia and nitrogen trifluoride gas as active species. For example, radio frequency (RF), direct current (DC) or microwave (MW) based discharge techniques can be used. The excitation can also be generated via a thermal based technique, a gas dissociation technique, a high intensity light source (eg, UV energy), or exposure to an x-ray source. Alternatively, a remote excitation source, such as a remote plasma generator, can be used to generate a plasma of the active material, which is then delivered to the processing chamber 300. Exemplary remote plasma generators are available from suppliers such as MKS Instruments, Inc. and Advanced Energy Industries, Inc. In an exemplary processing system, an RF power source is coupled to electrode 345. The high power microwave power source 346 is advantageous in situations where the power source 346 will also be used to generate active oxygen.

The temperature of each of the process chamber body 312 and the substrate can be controlled by flowing the heat transfer medium through the chamber body channel 313 and the support assembly channel 304, respectively. A support assembly channel 304 can be formed within the support assembly 301 to facilitate transfer of thermal energy. The chamber body 312 and the support assembly 310 can be individually cooled or heated. For example, the heating fluid can flow through one of the chamber body 312 and the support assembly 310 while the cooling fluid flows through the other of the chamber body 312 and the support assembly 310.

Other methods can be used to control the substrate temperature. The substrate can be heated by heating the support assembly 310 (or a portion of the support assembly 310, such as a base) with a resistive heater or via some other means. In another configuration, the gas delivery plate 320 can be maintained at a temperature above the substrate temperature and the substrate is raised to raise the substrate temperature. In this case, the substrate is heated by radiation, or the substrate is heated by conducting heat from the gas delivery plate 320 to the substrate using a gas. The substrate can be lifted by raising the support assembly 310 or by using a lifting bolt.

During the etching process described herein, in various embodiments, the chamber body 312 can be maintained at a temperature range between approximately 50 ° C and 80 ° C, between 55 ° C and 75 ° C, or between 60 ° C and 70 ° C. Inside. During exposure to the plasma effluent and/or oxidant, in various embodiments, the substrate can be maintained below about 100 ° C, below about 65 ° C, between about 15 ° C and about 50 ° C, or at about 22 ° C. And between about 40 ° C.

Plasma effluents include various molecules, molecular fragments, and ionized species. The current popular theory SiConi ^TM etching mechanism may or may not be entirely correct, but the plasma effluent is considered to include NH ₄ F and NH ₄ F.HF, NH ₄ F and NH ₄ F.HF and readily described herein Low temperature substrate reaction. The plasma effluent can react with the cerium oxide surface to form products (NH ₄ ) ₂ SiF ₆ , NH ₃ and H ₂ O. NH ₃ and H ₂ O are vaporized liquids under the processing conditions described herein and can be removed from treatment zone 340 via vacuum pump 325. A continuous or discontinuous thin layer of (NH ₄ ) ₂ SiF ₆ solid by-product remains on the surface of the substrate.

After the plasma effluent is exposed when the relatively high K film is removed from the low K material and the solid byproducts accumulate on the vertical walls of the trench (including the trench of the step), the substrate can be heated to remove the pair product. In an embodiment, the gas delivery plate 320 is heatable by combining the heating elements 370 within or adjacent to the gas delivery plate 320. The substrate can be heated by reducing the distance between the substrate and the heated gas delivery plate. In various embodiments, the gas delivery plate 320 can be heated to between about 100 ° C and 150 ° C, between about 110 ° C and 140 ° C, or between about 120 ° C and 130 ° C. By reducing the separation distance between the substrate and the heated gas delivery plate, in various embodiments, the substrate can be heated to above about 75 °C, above about 90 °C, above about 100 °C, or at about 115 °C and about Between 150 ° C. The heat radiated from the gas delivery plate 320 to the substrate should be sufficient to dissociate or sublimate the solid (NH ₄ ) ₂ SiF ₆ on the substrate into volatile products SiF ₄ , NH ₃ and HF, the volatile products SiF ₄ , NH ₃ and HF. It can be extracted from the processing area 340.

In various embodiments, ammonia (or, in general, a hydrogen-containing precursor) can be between about 50 sccm and about 300 sccm, between about 75 sccm and about 250 sccm, at about 100 sccm and about A flow rate between 200 sccm or between about 120 sccm and about 170 sccm flows into the distal plasma space 361. In various embodiments, the nitrogen trifluoride (or, in general, the fluorine-containing precursor) can be between about 25 sccm and about 150 sccm, between about 40 sccm and about 175 sccm, at about 50. A flow rate between sccm and about 100 sccm or between about 60 sccm and about 90 sccm flows into the distal plasma space 361. The combined flow of hydrogen-containing and fluorine-containing precursors into the remote plasma region can range from 0.05% to about 20% of the total gas mixing volume, with the remainder being carrier gases. In one embodiment, the scavenger or carrier gas is introduced into the distal plasma region prior to the reactive gases to stabilize the pressure in the distal plasma region.

The plasma effluent product is created in spaces 361, 362 and/or 363 by applying plasma energy to electrode 345 relative to the remainder of cap assembly 302. The plasma energy can be a combination of various frequencies or multiple frequencies. In an exemplary processing system, the plasma is provided by RF energy delivered to electrode 345. In various embodiments, the RF energy can be between about 1 W and about 1000 W, between about 5 W and about 600 W, between about 10 W and about 300 W, or at about 20 W and about Between 100 W. The RF frequency applied in the exemplary processing system can be less than about 200 kHz, less than about 150 kHz, less than about 120 kHz, or between about 50 kHz and about 90 kHz in different embodiments.

During the ashing process, active oxygen may be formed outside the processing chamber or in the same chamber (361-362), which is used to excite the etchant gas. In an embodiment, the active oxygen may comprise molecular oxygen with a more stable (O ₂₎ oxygen atoms (O) and ozone flow together (O _3), the combination of such active oxygen species is referred to herein. The flow rate of active oxygen may be between about 1 slm and about 50 slm, between about 2 slm and about 30 slm, or between about 5 slm and about 10 slm in different embodiments. The flow of reactive oxygen species may be combined with additional gas streams of associated inert gases (e.g., He, Ar) prior to entering the treatment zone 340 via opening 352. The inclusion of this associated inert carrier has a number of benefits including increased plasma density.

Processing zone 340 can be maintained at various pressures during the flow of ozone, oxygen, carrier gas, and/or plasma effluent into processing zone 340. The pressure can be maintained between about 500 mTorr and about 30 torr, between about 1 torr and about 10 torr, or between about 3 torr and about 6 torr in different embodiments. Low pressure can also be used within the processing zone 340. The pressure can be maintained at about 500 mTorr or less, about 250 mTorr or less, about 100 mTorr or less, about 50 mTorr or less, or about 20 mTorr or less, in various embodiments.

In one or more embodiments, the processing chamber 300 may be integrated into a variety of multi-processing platform, such multi-processing platform includes a Producer ^TM GT, Centura ^TM AP and Endura ^TM platform, the Producer ^TM GT, Centura ^TM AP and Endura ^TM The platform is available from Applied Materials, Inc., of Santa Clara, California. This type of processing platform can perform a variety of processing operations without breaking the vacuum.

FIG. 4 is a schematic top view of an illustrative multi-chamber processing system 400. System 400 can include one or more load lock chambers 402, 404 for transferring substrates into system 400 or out of system 400. Typically, because the system 400 is under vacuum, the load lock chambers 402, 404 can "pump down" the substrate in the introduction system 400. The first robot 410 can transfer the substrate between the load lock chambers 402, 404 and the first set of one or more substrate processing chambers 412, 414, 416, 418 (four substrate processing chambers are illustrated). Each of the processing chambers 412, 414, 416, 418 can be assembled in a kit to perform a plurality of substrate processing operations including, in addition to, cyclic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition ( In addition to CVD), physical vapor deposition (PVD), etching, pre-cleaning, degassing, orientation, and other substrate processes, the dry etching process described herein is also included.

The first robot 410 can also transfer the substrate to one or more of the transfer chambers 422, 424 or from one or more of the transfer chambers 422, 424. Transfer chambers 422, 424 can be used to maintain ultra-high vacuum conditions while transferring the substrate within system 400. The second robot 430 can transfer the substrate between the transfer chambers 422, 424 and the second set of one or more processing chambers 432, 434, 436, 438. Similar to processing chambers 412, 414, 416, 418, processing chambers 432, 434, 436, 438 can be assembled in kits for various substrate processing operations including, for example, including cyclic layer deposition (CLD), atomic layer deposition. In addition to (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, pre-cleaning, degassing, and orientation, the dry etching process described herein is also included. Any of the substrate processing chambers 412, 414, 416, 418, 432, 434, 436, 438 can be removed from the system 400 if it is not necessary for the particular process performed by the system 400. Gas may be provided by gas processing system 455, transported along the path, and mixed prior to delivery of the gas to the exemplary processing chamber.

System controller 457 is used to control motors, valves, flow controllers, power supplies, and other functions required to perform the process steps described herein. System controller 457 can rely on feedback from the optical sensor to determine and adjust the position of the movable mechanical assembly. The mechanical assembly can include a robot, a throttle, and a base that is moved by the motor under the control of the system controller 457.

In an exemplary embodiment, system controller 457 includes a hard disk drive (memory), a USB port, a floppy disk drive, and a processor. System controller 457 includes analog and digital input/output boards, interface panels, and stepper motor controller boards. The various portions of the multi-chamber processing system 400 including the processing chamber 300 are controlled by the system controller 457. The system controller executes the system control software in the form of a computer program stored on a computer readable medium (such as a hard disk, a floppy disk, or a flash memory flash drive). Other types of memory can also be used. The computer program includes a set of instructions that indicate timing, gas mixture, chamber pressure, chamber temperature, RF power level, base position, and other parameters of a particular process.

A process for depositing a film on a substrate or a process for cleaning the chamber 15 may be implemented using a computer program product executed by a controller. Computer code can be written in any general computer readable programming language: for example, 68000 combined languages, C, C++, Pascal, Fortran, or other programming languages. Use a general text editor to enter the appropriate code into a single file or multiple files and store or implement the appropriate code in a computer-usable medium, such as a computer's memory system. If the input code text is a high-level language, compile the code and then compile the final compiled code with pre-compiled Microsoft Windows The library code of the library routine is linked. In order to execute the compiled object code of the link, the system user invokes the object code to cause the computer system to load the code in the memory. The CPU then reads and executes the code to perform the tasks identified in the program.

The interface between the user and the controller can be via a touch sensitive display, and the interface between the user and the controller can also include a mouse and a keyboard. In one embodiment, two displays are used, one mounted in a clean room wall for use by an operator and the other behind a wall for service technicians. In the case where only one display is configured to receive input at one time, the two displays can simultaneously display the same information. In order to select a particular screen or function, the operator touches a designated area on the screen with a finger or a mouse. The touch area changes the highlight color of the touch area, or displays a new menu or screen, thereby confirming the operator's selection.

As used herein, a "substrate" may be a support substrate with or without a layer formed on a support substrate. The support substrate may be an insulator or a semiconductor having various doping concentrations and shapes, and the support substrate may be, for example, a semiconductor substrate having a type used in the manufacture of integrated circuits. The "yttria" layer is used as a simple expression of the cerium-containing material and the "yttria" layer can be used interchangeably with the cerium-containing material. Therefore, cerium oxide may include concentrations of other elemental components such as nitrogen, hydrogen, carbon, and the like. In some embodiments, cerium oxide consists essentially of cerium and oxygen. The gas in the "excited state" describes a gas in which at least some of the gas molecules are in an excited, dissociated, and/or ionized state. The gas may be a combination of two or more gases. The terms "groove" and "gap" are used throughout and do not imply that the etched geometry has a large horizontal azimuthal ratio. The grooves and gaps may appear as a circle, an ellipse, a polygon, a rectangle, or various other shapes when viewed from above the surface. The term "via" is used to refer to a trench of a lower horizontal azimuthal ratio (when viewed from above) that may or may not be filled with metal to form a vertical electrical connection.

Having described several embodiments, those skilled in the art will recognize that various modifications, alternatives, and equivalents can be used without departing from the spirit of the disclosed embodiments. In addition, many well-known processes and components are not described in order to avoid obscuring the invention. Therefore, the above description should not be taken as limiting the scope of the invention.

Where a range of values is provided, it is understood that each intermediate value between the upper and lower limits of the Each minor range between any intermediate value within any stated value or range and any other stated value or intermediate value within the specified range is included. The upper and lower limits of the small ranges may or may not be included in the range, and the invention also includes each of the ranges including the one of the threshold, the limit, or the total. Excludes any specific excluded threshold values within the scope of this regulation. When the stated range includes one or two thresholds, it also includes the exclusion of one or both of the limits included.

As used herein and the appended claims, the singular forms " " " " " " " " " " " " " " " " " " " " " " " " " " " Thus, for example, reference to "a process" includes a plurality of such processes, and reference to "the dielectric material" includes reference to one or more dielectric materials and equivalents known to those skilled in the art, and so forth.

In addition, the terms "including", "comprising" and "comprising", when used in the specification and the scope of the claims, are intended to be Or one or more other features, integers, elements, steps, operations or groups.

110. . . Low K material

120. . . Photoresist

125. . . SiCN layer

210-245. . . Steps

300. . . Processing room

302. . . Cover assembly

304. . . Support assembly channel

310. . . Support assembly

312. . . Room main body

313. . . Room main passage

320. . . Gas conveyor

322. . . Ring mounting flange

325. . . Vacuum pump

327. . . Throttle valve

329. . . Pump channel

330. . . Blocker assembly

331. . . Vacuum

333. . . bushing

335. . . Opening

340. . . Processing area

345. . . electrode

346. . . power supply

347. . . Electrical insulation ring

350. . . roof

351. . . Opening

352. . . Opening

360. . . Slit valve opening

361-363. . . region

370. . . Heating element

400. . . Processing system

402-404. . . Load lock room

410. . . First robot

412-418. . . Processing room

422-424. . . Transfer room

430. . . Second robot

432-438. . . Processing room

455. . . Gas treatment system

457. . . System controller

A further understanding of the features and advantages of the disclosed embodiments can be realized by reference to the <RTIgt;

1A-1B are cross-sectional views of a gap during processing in accordance with the disclosed embodiments.

2 is a flow diagram of a fill-filled photoresist removal process in accordance with the disclosed embodiments.

3 is a cross-sectional view of a processing chamber in accordance with the disclosed embodiments.

4 is a processing system in accordance with the disclosed embodiments.

In the drawings, the same elements and/or features have the same element symbols. Furthermore, various elements of the same type may be distinguished by a dash and a second symbol that distinguishes the same elements. If only the first component symbol is used in the specification, the description applies to any one of the same components having the same first component symbol, regardless of the second component symbol.

110. . . Low K material

120. . . Photoresist

125. . . SiCN layer

Claims (15)

A method of reducing the effective dielectric constant of a low K dielectric material between two trenches on a patterned substrate, the patterned substrate in a substrate processing region, wherein the low K dielectric A material forms a wall of the two trenches, the method comprising the steps of: transferring the patterned substrate into the substrate processing region; and vapor etching the patterned substrate to be removed from the low K dielectric material In addition to an external dielectric layer, the average dielectric constant of the low K dielectric material is reduced. The method of claim 1, wherein the step of vapor phase etching comprises the step of flowing a fluorine-containing precursor and a hydrogen-containing precursor into a first distal plasma region, the first distal plasma region and The substrate processing region is flow coupled while forming a plasma in the first distal plasma region to generate a plasma effluent; etching the pattern by flowing the plasma effluent into the substrate processing region a substrate while forming a solid by-product on the surface of the substrate; and sublimating the solid by-products by raising a temperature of the substrate above a sublimation temperature of the solid byproducts. The method of claim 2, wherein the fluorine-containing precursor comprises at least one precursor selected from the group consisting of nitrogen trifluoride, hydrogen fluoride, diatomic fluorine, monoatomic fluorine, and fluorine. Substituted hydrocarbons. The method of claim 2, wherein the hydrogen-containing precursor comprises at least one precursor selected from the group consisting of atomic hydrogen, molecular hydrogen, ammonia, a hydrocarbon, and a halogen. A completely substituted hydrocarbon. The method of claim 2, wherein during the operation of the step of sublimating the solid by-products, a temperature of the substrate is raised to about 100 ° C or higher. The method of claim 1, wherein the external dielectric layer has a dielectric constant greater than 3.0, and the remaining low K dielectric material has a dielectric constant less than 3.0. The method of claim 1, wherein the relatively high dielectric constant of the outer dielectric layer is caused by plasma ashing. The method of claim 1, further comprising the step of performing an ashing operation on the patterned substrate prior to the step of the vapor phase etching step. The method of claim 1 wherein the outer dielectric layer is removed from the walls of the two trenches. The method of claim 8, wherein the operation of ashing the patterned substrate occurs after the operation of transferring the patterned substrate into the substrate processing region. The method of claim 8, wherein the operation of plasma ashing the patterned substrate occurs prior to the operation of transferring the patterned substrate into the substrate processing region. The method of claim 1, wherein the outer dielectric layer has a thickness of about 150 Or smaller. The method of claim 1, wherein the etch rate of the outer dielectric layer exceeds the etch rate of the remaining low-k dielectric material by more than 50 times during the vapor phase etching process. The method of claim 1, wherein after the operation of vapor-etching the patterned substrate, the patterned substrate is subjected to plasma treatment in an atmosphere to remove the etched residue, the atmosphere comprising At least one of argon, nitrogen (N ₂ ), ammonia (NH ₃ ) or hydrogen (H ₂ ). The method of claim 14, wherein the etched residue comprises fluorine.