Methods for low temperature epitaxial deposition of phosporus-doped silicon

Abstract

An embodiment of a method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber includes heating a substrate positioned in a processing region of a processing chamber to a temperature less than 500 °C. In addition, the method includes flowing at least a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.

Description

44026055W001METHODS FOR LOW TEMPERATURE EPITAXIAL DEPOSITION OF PHOSPORUS-DOPED SILICONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 780,077, filed March 28, 2025, and entitled “Method of Silicon Phosphide Epitaxy at Low Temperature,” the contents of which are incorporated herein by reference.BACKGROUNDField

[0002] The present disclosure relates to improved apparatuses and methods in semiconductor processing.Description of the Related Art

[0003] Substrates are processed for a wide variety of applications, including the fabrication of integrated devices and microdevices. One method of processing substrates includes depositing a material, such as a semiconductor material or a conductive material, on an upper surface of the substrate. For example, epitaxy is a deposition process that deposits films of various materials on a surface of a substrate in a processing chamber. During processing, various parameters can affect the uniformity of material deposited on the substrate.

[0004] Currently, there is a demand for epitaxial deposition of phosphorus-doped silicon at low temperatures. Present solutions include using UV light or introducing hydrogen radicals. Conventional processing chambers require additional hardware in order to implement these solutions. Another solution to increase the growth rate is to use higher order silanes, which are expensive and require more complication delivery systems.

[0005] Therefore, a need exists for improved growth rate and selectivity of phosphorus-doped silicon for low temperature epitaxial chemical vapor deposition.44026055W001SUMMARY

[0006] By simultaneously flowing a silane precursor, a chlorinated silane precursor, and a phosphine gas, a phosphorus-doped silicon film can be grown epitaxially on a substrate at a low temperature at a higher growth rate than can be achieved with only a single silane source. In one embodiment, a method of depositing a phosphorus-doped silicon film onto a substrate disposed within a processing chamber includes heating the processing region to a temperature less than 500 °C; and flowing a plurality of gases into the processing chamber to deposit the phosphorus-doped silicon film, wherein the plurality of gases comprises a silane, a chlorinated silane, and a phosphine gas.

[0007] Some embodiments disclosed herein are directed to a method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber. The method includes heating a substrate positioned in a processing region of a processing chamber to a temperature less than 500 °C. In addition, the method includes flowing at least a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.

[0008] Some embodiments disclosed herein are directed to a method of depositing a phosphorus-doped silicon film onto a substrate. The method includes heating a processing region of a processing chamber to a temperature less than 450 °C. In addition, the method includes simultaneously flowing a plurality of gases into the processing chamber to deposit the phosphorus-doped silicon film on the substrate disposed therein. The plurality of gases comprises a silane, a chlorinated silane, and a phosphine gas and a ratio of silane precursors to phosphorous precursor is between 1:1 to 20:1. The silane comprises disilane (DS, Si2He). The chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiChH). Further, the method includes forming the phosphorus-doped silicon film so that the phosphorus-doped silicon film has a phosphorus concentration less than 6x1021atoms / cc.44026055W001

[0009] Some embodiments disclosed herein are directed to a method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber. The method includes heating a substrate positioned in a processing region of a processing chamber to a temperature less than 300 °C. In addition, the method includes flowing a plurality of gases into the processing chamber simultaneously to deposit the phosphorus-doped silicon film, the plurality of gases comprising a silane, a chlorinated silane, and a phosphine gas.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope and may be admitted to other equally effective embodiments.

[0011] FIG. 1 is a partial schematic cross-sectional view of a processing chamber, according to one or more embodiments disclosed herein.

[0012] FIG. 2 is a schematic block diagram of a method of substrate processing, according to one or more embodiments disclosed herein.

[0013] FIG. 3 is a chart showing a normalized growth rate and growth rate ratio for phosphorus-doped silicon films that are deposited on a substrate according to some embodiments disclosed herein.

[0014] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0015] By simultaneously flowing a silane precursor and a chlorinated silane precursor with a phosphine gas, phosphorus-doped silicon may grow epitaxially on a substrate at a low temperature at a higher growth rate than can be44026055W001achieved with only a single silane precursor. In some embodiments, a method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber includes heating the processing region to a temperature less than 500 °C having a substrate positioned therein; and flowing a plurality of gases including a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.

[0016] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, and may admit to other equally effective embodiments.

[0017] FIG. 1 is a schematic illustration of a type of deposition chamber 100 according to one implementation of the present disclosure. The deposition chamber 100 is utilized to grow an epitaxial film on a substrate, such as the substrate 102. The deposition chamber 100 may be used to perform embodiments of the methods described herein, such as, for example, the method 200 (FIG. 2). The deposition chamber 100 is configured to create a cross-flow of precursors across the top surface 150 of the substrate 102.

[0018] The deposition chamber 100 includes an upper body 156, a lower body 148 disposed below the upper body 156, a flow module 112 disposed between the upper body 156 and the lower body 148. The upper body 156, the flow module 112, and the lower body 148 define a chamber body for the deposition chamber 100. Disposed within the chamber body is a substrate support 106, an upper dome 108, a lower dome 110, a plurality of upper lamps 141, and a plurality of lower lamps 143. The substrate support 106 is disposed between the upper dome 108 and the lower dome 110. The plurality of upper lamps 141 are disposed between the upper dome 108 and a lid 154. The lid 154 includes a plurality of sensors 153 disposed therein for measuring the temperature within the deposition chamber 100. The plurality of lower lamps44026055W001143 are disposed between the lower dome 110 and a floor 152. The plurality of lower lamps 143 define a lower lamp assembly 145.

[0019] A processing region 136 is defined between the upper dome 108 and the lower dome 110. The processing region 136 has the substrate support 106 disposed therein. The substrate support 106 includes a top surface on which the substrate 102 is disposed. The substrate support 106 is attached to a shaft 118. The shaft 118 is connected to a motion assembly 121. The motion assembly 121 includes one or more actuators and / or adjustment devices that provide movement and / or adjustment of the shaft 118 and / or the substrate support 106 within the processing region 136. The motion assembly 121 includes a rotary actuator 122 that rotates the shaft 118 and / or the substrate support 106 about a longitudinal axis A of the deposition chamber 100. The motion assembly 121 further includes a vertical actuator 124 to lift and lower the substrate support 106 in the z-direction. The motion assembly 121 includes a tilt adjustment device 126 that is used to adjust the planar orientation of the substrate support 106 and a lateral adjustment device 128 that is used to adjust the position of the shaft 118 and the substrate support 106 side to side within the processing region 136.

[0020] The substrate support 106 may include lift pin holes 107 disposed therein. The lift pin holes 107 are sized to accommodate a lift pin 132 for lifting of the substrate 102 from the substrate support 106 either before or after a deposition process is performed. The lift pins 132 may rest on lift pin stops 134 when the substrate support 106 is lowered from a processing position to a transfer position.

[0021] The flow module 112 includes a plurality of process gas inlets 114, a plurality of purge gas inlets 164, and one or more exhaust gas outlets 116. The plurality of process gas inlets 114 and the plurality of purge gas inlets 164 are disposed on the opposite side of the flow module 112 from the one or more exhaust gas outlets 116. One or more flow guides 146 are disposed below the plurality of process gas inlets 114 and the one or more exhaust gas outlets 116. The flow guide 146 is disposed above the purge gas inlets 164. A liner 163 is disposed on the inner surface of the flow module 112 and protects the flow44026055W001module 112 from reactive gases used during deposition processes. The process gas inlets 114 and the purge gas inlets 164 are positioned to flow a gas parallel to the top surface 150 of a substrate 102 disposed within the processing region 136. The process gas inlets 114 are fluidly connected to a process gas source 151. The purge gas inlets 164 are fluidly connected to a purge gas source 162. The one or more exhaust gas outlets 116 are fluidly connected to an exhaust pump 157. Each of the process gas source 151 and the purge gas source 162 may be configured to supply one or more precursors or process gases into the processing region 136.

[0022] The deposition chamber 100 further includes a controller 120. The controller 120 can include a central processing unit (CPU) 170, memory 135, and support circuits (or I / O) (not shown). The CPU 170 may be one of any form of computer processors that are used in industrial settings for controlling various processing and hardware (e.g., process gas delivery, purge gas delivery, and other hardware) and monitor the processes (e.g., processing time, susceptor and / or substrate position, power to the lamp assemblies). The memory 135 is connected to the CPU 170, and may be one or more of readily available memory, such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, or any other form of digital storage, local or remote. Software instructions and data can be coded and stored within the memory 135 for instructing the CPU 170. The support circuits 158 are also connected to the CPU 170 for supporting the processor in a conventional manner. The support circuits 158 may include conventional cache, power supplies, clock circuits, input / out circuitry, subsystems, and the like. A program (or computer instructions) readable by the controller 120 determines which tasks are performable. The program may be software readable by the controller 120 and may include code to monitor and control (e.g., switch between), for example, the various gas sources (e.g. one or more precursor gases, phosphorous-containing source gas, the one or more deposition gases, the n-type dopant gas). The controller 120 may be used to provide instructions to the deposition chamber 100 to perform the methods described herein, for example, the method 200.44026055W001

[0023] FIG. 2 is a schematic block diagram of a method 200 of substrate processing, according to one or more embodiments disclosed herein. Methods according to one or more embodiments contemplated herein may be performed in a processing chamber such as the exemplary processing chamber 100 set forth and described with reference to FIG. 1.

[0024] Operation 202 of method 200 includes positioning a substrate on a substrate support in a processing region (e.g., processing region 136 of FIG. 1) of a deposition chamber. In one or more embodiments, the positioning includes moving a substrate support (e.g., substrate support 106 of FIG. 1) and / or a plurality of lift pins (e.g., lift pins 132 of FIG. 1) relative to each other to land the substrate on the substrate support.

[0025] Operation 204 of the method 200 includes heating the processing region of the deposition chamber to a predetermined temperature. In some embodiments, the predetermined temperature may be in a range of from about 300 °C to about 600 °C, such as from about 350 °C to about 500 °C, such as from about 350 °C to about 400 °C, such as less than about 500 °C, such as less than about 450 °C, such as less than about 400 °C, such as less than about 350 °C, or such as less than about 300 °C.

[0026] Operation 206 of the method 200 includes flowing one or more precursor gases over the substrate to process the substrate. In one or more embodiments, the temperature of the processing region during the flowing of the precursor gases is the predetermined temperature of operation 204. Thus, in some embodiments, the temperature of the processing region may be in a range of from about 300 °C to about 600 °C, such as from about 350 °C to about 500 °C, such as from about 350 °C to about 400 °C, such as less than about 500 °C, such as less than about 450 °C, such as less than about 400 °C, such as less than about 350 °C, or such as less than about 300 °C.

[0027] In some embodiments, the one or more precursor gases may comprise a silane precursor, a chlorinated silane precursor, and a phosphine gas. The one or more precursor gases flow from a process gas source (e.g., process gas source 151) and into the processing region of the deposition44026055W001chamber. The one or more precursor gases are delivered into the processing chamber and flow across the substrate surface within the processing region. By simultaneously flowing the silane precursor, a chlorinated silane precursor, and a phosphine gas in a deposition chamber (e.g., deposition chamber 100 of Figure 1 ) at temperatures of about 300 °C to about 600 °C, a phosphorus-doped silicon film may be grown epitaxially on a substrate at an elevated growth rate. For instance, in some embodiments, the growth rate of the phosphorus-doped silicon film may be characterized by a growth rate ratio that comprises a growth rate of crystalline film to amorphous film. In some embodiments, the growth rate ratio of the epitaxially grown phosphorus-doped silicon film on the substrate via embodiments of the method 200 may be in a range of from about 1.0 to about 10.0, such as from about 1.0 to about 8.0, such as from about 1.0 to about 3.0, such as from about 1.2 to about 2.2, or such as from about 1.4 to about 2.2. Achieving these example growth rate ratios is an improvement over conventional processes which do not simultaneously flow precursor gases comprising a silane precursor, a chlorinated silane precursor, and a phosphine gas into a deposition chamber. In some examples, the growth rate ratio of the phosphorus-doped silicon film may be at least two times that of conventional processes and can be even higher.

[0028] In some embodiments, one or more of the silane precursor, chlorinated silane precursor, and phosphine gas may be flowed into the processing region with a carrier gas. For instance, in some embodiments, the carrier gas may include hydrogen, nitrogen, and / or another suitable carrier gas. In some embodiments, the carrier gas may comprise an inert gas.

[0029] In some examples, a ratio of the silicon precursors to the phosphorous precursors in the one or more precursor gases is in a range of from about 1:1 to about 20:1, such as from about 5:1 to about 20:1, such as from 8:1 to about 20:1, such as from about 9:1 to about 19:1, such as from about 10:1 to about 18: 1 , such as from about 12:1 to about 16: 1 , such as from about 13:1 to about 15: 1 , or such as about 14:1.

[0030] In some examples, the silane precursor is flowed into the processing region as a gas at a flow rate in a range of from about 50 standard cubic44026055W001centimeters per minute (seem) to about 2000 seem, such as from about 700 seem to about 1500 seem, such as between about 900 seem to about 1500 seem, such as between about 1000 seem and about 1500 seem, such as between about 1050 seem to about 1500 seem, such as greater than 1000 seem, such as greater than 1100 seem, such as greater than 1200 seem. In some examples, the silane precursor may comprise molecules having a single silicon atom, and / or may comprise molecules having two or more silicon atoms. Silicon precursors (or precursor molecules) that have two or more silicon atoms may be referred to herein as “high-order silicon precursors.” Some specific examples of the silane precursor may include silane (S i H4) , disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof.

[0031] In some examples, the chlorinated silane gas precursor is flowed into the processing region at a flow rate in a range of from about 50 seem to about 2000 seem, such as from about 100 seem to about 1000 seem. In some examples, the chlorinated silane precursor comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof.

[0032] In some examples, the phosphine gas is flowed into the processing region at a flow rate in a range of from about 20 seem to about 600 seem, such as about from about 40 seem to about 100 seem, such as from about 50 seem to about 90 seem. In some examples, the phosphine gas precursor comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

[0033] In some embodiments, such as when TBP is utilized as the phosphine gas, the phosphine gas may be flowed into the processing region (e.g., processing region 136 in FIG. 1) may be lowered relative to the previously described example ranges. For instance, in some embodiments, the phosphine gas may be flowed into the processing region at a flow rate in a range of from about 0.2 seem to about 600 seem. In addition, due to the potentially lower flow rate of the phosphine gas when TBP is utilized, the ratio of ratio of the silicon precursors to the phosphorous precursors in the one or more precursor gases may also be increased to be in a range from about 1 :1 to about 2000:1.44026055W001

[0034] In some examples, one or more precursor gases (e.g., the silane precursor, the chlorinated silane precursor, and the phosphine gas) are flowed into a processing region of the deposition chamber for a period of time that ranges from about 30 seconds to about 3000 seconds, such as from about 60 seconds to about 600 seconds, such as from about 120 seconds to about 540 seconds, such as from about 180 seconds to about 480 seconds, such as from about 240 seconds to about 480 seconds, such as from about 300 seconds to about 480 seconds, such as from about 360 seconds to about 480 seconds, or such as about 420 seconds.

[0035] In some examples, the phosphorus concentration ([P]) of the phosphorus-doped silicon film grown epitaxially on a substrate by use of embodiments of method 200 is less than or equal to about 6x1021atoms per cubic centimeter (atoms / cc), such as less than or equal to about 5x1021atoms / cc, or such as less than or equal to about 1x1021atoms / cc. In some embodiments, the phosphorus content (or concentration) of the phosphorus-doped silicon film may be about 12 atomic percent (at%) or less, such as about 10 at% or less, such as about 9 at% or less, such as about 8 at% or less, such as about 7 at% or less, such as about 6 at% or less, or such as about 5 at% or less.

[0036] In one or more examples, embodiments of method 200 are applied to the deposition of epitaxial phosphorus-doped silicon films on patterned substrates, where deposition is desired only on the exposed Si areas. For example, deposition of amorphous silicon films must be removed by etching with HCI and or CI2. Method 200 may increase the growth rate of crystalline phosphorus-doped silicon relative to the growth rate of amorphous phosphorus-doped silicon due to the presence of chlorine from the chlorinated silane precursor during deposition. The increased deposition rate of crystalline phosphorus-doped silicon relative to amorphous phosphorus-doped silicon may be characterized by the example growth rate ratio as previously described. By promoting the growth rate of crystalline phosphorus-doped silicon over amorphous phosphorus-doped silicon, the window for the selective process is44026055W001increased. This in turn allows for quicker removal of amorphous phosphorus-doped silicon, which thereby improves efficiency, cost, and throughput.

[0037] In some embodiments, the phosphorus-doped silicon film may comprise silicon phosphide (SiP). In some embodiments, the phosphorus-doped silicon film may comprise SiP doped with other elements, such as carbon (e.g., SiCP), boron, or arsenic.

[0038] FIG. 3 is a chart that illustrates a normalized growth rate 300 and growth rate ratios 302, 304, 306 of a phosphorus-doped silicon film that is deposited on a substrate by use of embodiments of the methods described herein (such as embodiments of the method 200 in FIG. 2). More specifically, FIG. 3 illustrates the normalized growth rate 300 and growth rate ratios 302, 304, 306 of SiP films. The SiP films may be deposited on a substrate having thermally formed silicon oxide (SiC ) deposited thereon.

[0039] The chart of FIG. 3 shows the normalized growth rate 300 and growth rate ratios 302, 304, 306 for four different precursor gasses (Gas 1 , Gas 2, Gas 3, Gas 4). These different precursor gases are flowed into the processing region (e.g., processing region 136 in FIG. 1) of a processing chamber to epitaxially grow the SiP films on a substrate. The general content of Gas 1, Gas 2, Gas 3, and Gas 4 are provided below in Table 1.Table 1

[0040] Gases 1-4 may each include disilane and phosphine. In addition, Gases 2-4 may additionally include dichlorosilane (as the chlorinated silane precursor). For the example of FIG. 3, the flow rate of the Gases 1-4 is in a range of from about 100 seem to about 600 seem, and the temperature during the film deposition is in a range of from about 400°C to about 450°C.44026055W001

[0041] As illustrated in FIG. 3, normalized growth rate 300 comprises the normalized growth rate of crystalline SiP (c-SIP) on the substrate. As is shown in FIG. 3, the normalized growth rate 300 of c-SIP increases as the content of chlorinated silane is increased in the precursor gases (Gas 1 , Gas 2, Gas 3, Gas 4). In addition, as is also illustrated in FIG. 3, the growth rate ratios 302, 304, 306, which may comprise a ratio of c-SiP to amorphous SiP (a-SiP) may also increase as the content of chlorinated silane is increased in the precursor gases (Gas 1, Gas 2, Gas 3, Gas 4).

[0042] In some embodiments, a method of depositing a phosphorus-doped silicon film (such as a SiP film) onto a substrate within a processing chamber includes heating a substrate positioned in a processing region of a processing chamber to a temperature less than about 500 °C; and flowing at least a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.

[0043] The silane may comprise silane (SiF ), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof. The silane may have a flow rate in a range of from about 50 seem to about 2000 seem, such as greater than 1000 seem.

[0044] The chlorinated silane may comprise dichlorosilane (DCS, SiFhCF), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof. The chlorinated silane may have a flow rate in a range of from about 50 seem to about 2000 seem, such as greater than 1000 seem.

[0045] The phosphine gas may comprise phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof. The phosphine gas has a flow rate in a range of from about 0.2 seem to about 600 seem, such as about 40 seem to about 100 seem, or such as about 50 seem to about 90 seem.

[0046] The plurality of gases (including the silane precursor, chlorinated silane precursor, and phosphine gas) may be flowed into the processing chamber simultaneously. In some embodiments, the plurality of gases are44026055W001flowed into the processing chamber for a time period that ranges from 30 seconds to about 3000 seconds, such as about 100 seconds to about 600 seconds, or such as about 300 seconds to about 480 seconds. A phosphorus concentration of the phosphorus-doped silicon film is less than about 6x1021atoms / cc, such as less than about 5x1021atoms / cc, or such as less than about 1x1021atoms / cc. The temperature in the processing chamber may be less than about 500°C, such as less than about 450 °C, such as less than about 400 °C, such as less than about 350 °C, or such as less than about 300 °C. A ratio of silicon precursors to a phosphorous precursor in the plurality of gases is in range of from about 1 : 1 to about 2000: 1 , such as from about 10:1 to about 18:1, or such as about 14:1.

[0047] In some embodiments, a method of depositing a phosphorus-doped silicon film (such as a silicon phosphide (SiP) film) onto a substrate includes heating a processing region of a processing chamber to a temperature less than about 450 °C; and simultaneously flowing a plurality of gases into the processing chamber to deposit the phosphorus-doped silicon film on the substrate disposed therein, wherein: the plurality of gases comprises a silane precursor, a chlorinated silane precursor, and a phosphine gas and a ratio of silane precursors to phosphorous precursor is in a range of from about 1:1 to about 20: 1 , such as from about 10: 1 to about 18:1; the silane comprises disilane (DS, Si2He); the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiChH); and forming a phosphorus-doped silicon film having a phosphorus concentration less than about 6x1021atoms / cc, such as less than about 5x1021atoms / cc, or such as less than about 1x1021atoms / cc.

[0048] As explained above and reiterated below, the present disclosure includes, without limitation, the following Examples.

[0049] Example 1 : A method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber, the method comprising: heating a substrate positioned in a processing region of a processing chamber to a temperature less than 500 °C; and flowing at least a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.44026055W001

[0050] Example 2: The method of any of the Examples, wherein the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof.

[0051] Example 3: The method of any of the Examples, wherein the silane comprises disilane (DS, Si2He).

[0052] Example 4: The method of any of the Examples, wherein the silane and the chlorinated silane each have a flow rate that is in a range of from about 50 standard cubic centimeters per minute (seem) to about 2000 seem.

[0053] Example 5: The method of any of the examples, wherein the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiC H), tetrachlorosilane (SiCk), or combinations thereof.

[0054] Examples 6: The method of any of the Examples, wherein the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiCbH).

[0055] Example 7: The method of any of the Examples, wherein the phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

[0056] Example 8: The method of any of the Examples, wherein the phosphine gas has a flow rate between 0.2 standard cubic centimeters per minute (seem) to about 600 seem.

[0057] Example 9: The method of any of the Examples, wherein flowing the silane, the chlorinated silane, and the phosphine gas into the processing chamber further comprises flowing the silane, the chlorinated silane, and the phosphine gas into the processing chamber simultaneously.

[0058] Example 10: The method of any of the Examples, wherein the silane comprises a high-order silane precursor.44026055W001

[0059] Example 11: The method of any of the Examples, wherein a phosphorus concentration of the phosphorus-doped silicon film is less than 6x1021atoms / cc.

[0060] Example 12: The method of any of the Examples, wherein the temperature is less than 400 °C.

[0061] Example 13: The method of any of the Examples, wherein a ratio of silicon precursors to phosphorous precursors in the silane, chlorinated silane, and phosphine gas is in a range of from about 1:1 to about 2000:1.

[0062] Example 14: The method of any of the Examples, wherein: the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof; the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof; and the phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

[0063] Example 15: A method of depositing a phosphorus-doped silicon film onto a substrate, the method comprising: heating a processing region of a processing chamber to a temperature less than 450 °C; simultaneously flowing a plurality of gases into the processing chamber to deposit the phosphorus-doped silicon film on the substrate disposed therein, wherein: the plurality of gases comprises a silane, a chlorinated silane, and a phosphine gas and a ratio of silane precursors to phosphorous precursor is between 1:1 to 20:1 ; the silane comprises disilane (DS, Si2He); and the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiCIsH); and forming the phosphorus-doped silicon film so that the phosphorus-doped silicon film has a phosphorus concentration less than 6x1021atoms / cc.

[0064] Example 16: The method of any of the Examples, wherein the phosphine gas comprises tertiarybutylphosphine (TBP, C4H11P).

[0065] Example 17: The method of any of the Examples, wherein the phosphine gas has a flow rate between 0.2 standard cubic centimeters per44026055W001minute (seem) to about 600 seem, and the ratio of silicon precursors to phosphorous precursors in the plurality of gases is in a range of from about 1:1 to about 2000:1.

[0066] Example 18: A method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber, the method comprising: heating a substrate positioned in a processing region of a processing chamber to a temperature less than 300 °C; and flowing a plurality of gases into the processing chamber simultaneously to deposit the phosphorus-doped silicon film, the plurality of gases comprising a silane, a chlorinated silane, and a phosphine gas.

[0067] Example 19: The method of any of the Examples, wherein: the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof; the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof; and the phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

[0068] Example 20: The method of any of the Examples, wherein a ratio of silane precursors to phosphorous precursors in the plurality of gases is in a range from about 1 : 1 to about 2000: 1.

[0069] The preceding discussion is directed to various embodiments. However, one of ordinary skill in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.

[0070] The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.44026055W001

[0071] Implementations and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. Implementations described herein can be implemented as one or more non-transitory computer program products, i.e., one or more computer programs tangibly embodied in a machine readable storage device, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple processors or computers.

[0072] The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0073] The term "data processing apparatus" encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer.

[0074] Computer readable media suitable for storing computer program instructions and data include all forms of nonvolatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM44026055W001and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0075] In the preceding discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection of the two devices, or through an indirect connection that is established via other devices, components, nodes, and connections. In addition, when used herein (including in the claims), the words “about,” “generally,” “substantially,” “approximately,” and the like, when used to refer to a stated value, mean within a range of plus or minus 10% of the stated value.

[0076] While exemplary embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems, apparatus, and processes described herein are possible and are within the scope of the disclosure. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the operations in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before operations in a method claim are not intended to and do not specify a particular order to the operations, but rather are used to simplify subsequent reference to such operations.

Claims

44026055W001What is claimed is:

1. A method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber, the method comprising:heating a substrate positioned in a processing region of a processing chamber to a temperature less than 500 °C; andflowing at least a silane, a chlorinated silane, and a phosphine gas into the processing chamber to deposit the phosphorus-doped silicon film.

2. The method of claim 1, wherein the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof.

3. The method of claim 1, wherein the silane comprises disilane (DS, Si2He).

4. The method of claim 1, wherein the silane and the chlorinated silane each have a flow rate that is in a range of from about 50 standard cubic centimeters per minute (seem) to about 2000 seem.

5. The method of claim 1, wherein the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof.

6. The method of claim 1, wherein the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiChH).

7. The method of claim 1 , wherein the phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

8. The method of claim 1, wherein the phosphine gas has a flow rate between 0.2 standard cubic centimeters per minute (seem) to about 600 seem.44026055W0019. The method of claim 1 , wherein flowing the silane, the chlorinated silane, and the phosphine gas into the processing chamber further comprises flowing the silane, the chlorinated silane, and the phosphine gas into the processing chamber simultaneously.

10. The method of claim 1 , wherein the silane comprises a high-order silane precursor.

11. The method of claim 1, wherein a phosphorus concentration of the phosphorus-doped silicon film is less than 6x1021atoms / cc.

12. The method of claim 1 , wherein the temperature is less than 400 °C.

13. The method of claim 1, wherein a ratio of silicon precursors to phosphorous precursors in the silane, chlorinated silane, and phosphine gas is in a range of from about 1 : 1 to about 2000: 1.

14. The method of claim 1 , wherein:the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof;the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof; andthe phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

15. A method of depositing a phosphorus-doped silicon film onto a substrate, the method comprising:heating a processing region of a processing chamber to a temperature less than 450 °C;44026055W001simultaneously flowing a plurality of gases into the processing chamber to deposit the phosphorus-doped silicon film on the substrate disposed therein, wherein:the plurality of gases comprises a silane, a chlorinated silane, and a phosphine gas, wherein a ratio of silane precursors to phosphorous precursors in the plurality of gases is between 1:1 to 20:1 ;the silane comprises disilane (DS, Si2He); andthe chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2) or trichlorosilane (TCS, SiChH); andforming the phosphorus-doped silicon film so that the phosphorus-doped silicon film has a phosphorus concentration less than 6x1021atoms / cc.

16. The method of claim 15, wherein the phosphine gas comprises tertiarybutylphosphine (TBP, C4H11P).

17. The method of claim 16, wherein the phosphine gas has a flow rate between 0.2 standard cubic centimeters per minute (seem) to about 600 seem, and the ratio of silicon precursors to phosphorous precursors in the plurality of gases is in a range of from about 1 : 1 to about 2000: 1.

18. A method of depositing a phosphorus-doped silicon film onto a substrate within a processing chamber, the method comprising:heating a substrate positioned in a processing region of a processing chamber to a temperature less than 300 °C; andflowing a plurality of gases into the processing chamber simultaneously to deposit the phosphorus-doped silicon film, the plurality of gases comprising a silane, a chlorinated silane, and a phosphine gas.44026055W00119. The method of claim 18, wherein:the silane comprises silane (SiH4), disilane (DS, Si2He), trisilane (SisHs), tetrasilane (Si4H ), or combinations thereof;the chlorinated silane comprises dichlorosilane (DCS, SiH2Cl2), trichlorosilane (TCS, SiChH), tetrachlorosilane (SiCk), or combinations thereof; andthe phosphine gas comprises phosphine (PH3), phosphorus trichloride (PCI3), tertiarybutylphosphine (TBP, C4H11P), or combinations thereof.

20. The method of claim 19, wherein a ratio of silane precursors to phosphorous precursors in the plurality of gases is in a range from about 1 :1 to about 2000:1.

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