TWI333257B - Method of producing simox substrate - Google Patents

Description

1333257 IX. Description of the Invention: [Technical Field] The present invention relates to a method for fabricating a SIMOX substrate and a SIMOX substrate prepared by the method, which is a buried crystal layer (Buried Oxide) in &gt; Among the SOI (Silicon-On-Insulator) substrates in which a single crystal ruthenium layer (hereinafter referred to as 8 〇 1 layer) is formed, a SiMOX (Separation by Implanted Oxygen) technique is employed. In detail, the manufacturing method of the SIM〇x substrate # which can be effectively intercepted due to the heavy metal contamination of the device process and the SIMOX substrate produced by the method. [Prior Art] The μ SOI substrate has the following excellent characteristics: (丨) can reduce the parasitic capacitance between the device and the substrate, and can speed up the operation of the device, which is superior to the radiation withstand voltage, and (3) easy separation of the medium and high collectivization (4) It is possible to improve the Latch up characteristics and the like. At present, the manufacturing methods of s〇i substrates are divided into two categories. One of the methods is a small-film active wafer, which is bonded to the supporting wafer, and the other method is to implant oxygen ions from the surface of the wafer, and form a buried oxide on the surface of the wafer to a predetermined depth. The SIMOX method of the layer. In particular, the SIM〇x method is an effective method that is expected to be expected due to a small number of manufacturing processes. The manufacturing method of the SIMOX substrate is: after the mirror surface processing is performed on the main surface of the single crystal substrate, the implantation process of implanting oxygen ions into the substrate at a predetermined depth by the oxygen implantation method is performed on the mirror surface. And a high-temperature heat treatment process in which a substrate having an oxygen ion implanted in a oxidizing atmosphere is subjected to a heat treatment to form a buried oxide layer in the substrate. 8 6 1333257 Specifically, the temperature of the dream single crystal substrate is maintained at 5 ° ° C ~ 650 ° C, and the surface of the substrate is implanted with about 1 〇 17 〇 1 〇 18 / cm 2 of oxygen atom ions or oxygen molecular ion implants. Enter the specified depth. Then, the substrate implanted with oxygen ions is placed in a heat treatment furnace maintained at a temperature of 500 ° C to 70 ° ° C, and in a state where slip prevention is prevented, the temperature is gradually increased to about ～1390 ° C. Heat treatment for about 10 hours. This high-temperature heat treatment causes oxygen ions implanted inside the substrate to react with the stone to form a buried oxide layer inside the substrate. The other party in the device manufacturing process, the metal that can directly adversely affect the device characteristics, the getter technology that can be removed from the substrate surface, the method of sandblasting the back surface of the substrate, and the method of depositing the polycrystalline germanium film on the back side of the substrate. The method of implanting a high concentration of ruthenium on the back side of the substrate is an external gettering method, but the internal gettering method (intrinsic Gettering) caused by the crystal defects caused by the oxygen deposit deposited inside the ruthenium substrate It is superior to mass production and has been used in mass production for clean inhalation. However, 'SIMOX substrate is generally used to form a buried oxide layer inside the substrate' and f is implanted with oxygen ions after heat treatment at a temperature of about 13 〇 (rc), so the heat treatment of the horse is to form an inhalation depression in the surface layer. Oxygen deposits are difficult. In order to solve the above problems, there is a method for manufacturing a semiconductor substrate. After implanting oxygen ions on a single crystal substrate, the substrate is placed in a hydrogen gas atmosphere or a nitrogen atmosphere containing a small amount of oxygen. After heat treatment at a temperature of 1200 to 1300 ° C for 6 to 12 hours to form a buried oxide layer, 7 1333257 heat treatment from low temperature to high temperature step by step or continuous elevated temperature. Patent Information 1). This special teacher shows the specific (4) = ginseng from 50 (the phase-by-stage heat treatment method started by TC, with 5〇~i〇q= pieces, the sections are successively raised, and the final temperature is 85 degrees 〇C). The ^th order heat treatment method starts from 50 (TC starts from 0.2 to 1 and has a final temperature of (4) C. However, in order to form a second degree, the buried layer of the plate is subjected to a high temperature heat treatment of about 1300 ΐ. Secondly, the oxygen deposition nucleus is reduced and eliminated. Therefore, the heat treatment conditions indicated by the above patent == will inhibit the growth of oxygen deposits = 2 and reach a temperature of 850 ° C to obtain sufficient gettering effect. Also, there is a SIMOX substrate and The suggestion of the manufacturing method is that there is a part in which no buried oxide layer is formed, and the structure of the getter device is referred to as a crystal defect or a shape on the back surface of the sheet or the surface of the single crystal substrate (refer to, for example, Patent Document 2^ In this patent document 2, a fragment-like buried oxide layer is formed in the vicinity of the surface layer, and an oxygen deposition nucleus is formed in the range of 500 to 9 〇〇t for the heat treatment condition of the gettering, and the twist is 1〇5/cm3~ 1〇9/cm3 range, and 2nd heat 1 The range of GGG~115()ΐ is such that the above deposited core growth ί deposit is also possible. However, in the embodiment, SIM0X of the prior art, that is, SMOX which fully grows the buried oxide film on the wafer, is used as a comparative sample to evaluate The amount of crystal defects on the surface of the substrate caused by the quantitative contamination of heavy metals is high. The surface defects of the examples in which the ruthenium oxide film is buried are hardly observed. In contrast, the previous SIMl〇x observed 1 〇5~1〇6 1333257/cm2 pits and lamination defects. That is, it means that the patented data 2 has not yet fully established the gettering technique. Patent Document 1: Japanese Patent Laid-Open No. 7 193072 Patent Information 2: Japanese Laid-Open Patent Publication No. Hei. No. 5,825,525, the entire disclosure of which is incorporated herein by reference. However, the defect _ layer has an inhalation effect (see, for example, Non-patent Data 1). That is, according to the contents of the non-patent data 1, a sudden heavy metal occurs in the manufacturing process of the SIMOX substrate. In the case of contamination, when the oxygen deposit of the SIMOX substrate is not able to obtain sufficient gettering effect as described in the above Patent No. 2 or the above Patent Document 3, the defect layer immediately below the buried oxide layer is also trapped of heavy metals. In recent years, there is a need for thinning in the SOL layer of the SIMOX substrate. Therefore, the field of heavy metal contamination intercepted by the defect layer directly under the buried oxide layer has an influence on the device characteristics. Therefore, the design of the SIMOX substrate requires an inhalation source. At least the device can not be affected by its characteristics, and the sudden heavy metal pollution in the process can be effectively intercepted. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for fabricating a SIMOX substrate and a SIMOX substrate obtained by the method, which can reduce the concentration of heavy metal intercepted by the defect layer and effectively capture heavy metals inside the body layer. The invention of claim 1 is as shown in FIG. 1(a) to FIG. 1(e), and is an improvement of the manufacturing method of the 9 1333257 SIMOX substrate, which comprises an oxygen implantation process and internal implantation of the germanium wafer 11. Oxygen ions; and a first heat treatment performed by the wafer 11 in a gas atmosphere in which oxygen and an inert gas are mixed at 1300 to 1390 ° C to form a buried oxide layer 12 in the field of the wafer 11 to a predetermined depth, and at the same time The step of burying the surface of the wafer on the oxide layer 12 to form the SOI layer 13 is performed. This characteristic composition consists of: • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • VIII / wu < oxygen concentration 'to form a buried oxide layer 12 on the wafer, so that the first heat-treated wafer in a hydrogen, argon, nitrogen, oxygen or a mixed gas atmosphere, at a temperature of 4 〇〇 ~ 9 (8) C Maintaining a second heat treatment for 1 to 96 hours to form a deposition layer Ub on the surface layer 14 further below the defect layer 14 formed directly under the buried oxide layer; and a wafer subjected to the second heat treatment in hydrogen, argon, In the atmosphere of nitrogen, oxygen or a mixed gas thereof, the third heat treatment is performed at a temperature higher than the second heat treatment temperature for 1 to 96 hours, and the oxygen deposition core 14b formed on the body layer 14 is grown into an oxygen deposit. The process is obtained according to the invention of claim , under the defect layer 14a, 14 having an oxygen source formed by the oxygen deposit 14c.

1〇SIM〇x substrate with MX size of 50nm or more. Treatment: The invention is the invention of claim 1 in the scope of the second 哉 = part or the full range. A manufacturing method in which the temperature is raised from the range of 1 to 96 hours at a speed of U to 20 8 10 1333257 C/min, from the softness to the one-to-one range of the 125th generation. The invention of claim 3 provides a The improvement of the simox substrate manufacturing method includes: a step of implanting oxygen ions inside the Shixi wafer 11; and a 矽 wafer 11 in an atmosphere of oxygen and an inert gas and a mixed gas to measure the ith heat treatment of the (9) generation And forming a 801 layer 13 on the surface of the wafer on the buried oxide layer 12 while forming the buried oxide layer 12 from the surface to the predetermined depth. The characteristic composition comprises: in the oxygen ion implantation The first stone wafer 11 has 8x1〇7~l.8x 1018at〇ms/cm# ASTM) oxygen concentration, forming a buried oxide layer 12 in whole or part of the wafer, so that the first heat treated wafer is 1050~135 (after the TC is kept for 1 to 900 seconds, then: the rapid cooling is performed at a temperature drop rate of lGt:/sec or more, so that the cavity layer 14 is buried in the body layer 14 below the buried oxide layer 12; Reduced wafers in oxygen, gas, &amp; hydrogen, or such a mixture In the body atmosphere, the process is performed at 500 to 1000. (The second heat treatment is performed in 丨 to 96 hours, and the surface layer 14' formed below the body layer 14 directly under the buried oxide layer 12 forms the oxygen deposition core 14b. According to the invention of the third aspect, the SIMOX substrate which is subjected to the second heat treatment step is subjected to heat treatment at the semiconductor device manufacturing process, and the oxygen deposition core is grown into an oxygen deposit, so that the wafer can have an IG overall. The invention of the patent application 4 is related to the manufacturing method of the application for the lion 3, which further includes 'the wafer to be subjected to the second heat treatment, in oxygen, nitrogen, argon, 1333257

The hydrogen or the mixed gas atmosphere is subjected to heat treatment at a temperature higher than 900 to 1250 ° C for 1 to 96 hours to grow the oxygen-deposited core formed on the body layer 14 into the oxygen deposit 14c. X The invention of Patent No. 5 is related to the manufacturing method of Patent Application No. 3 in the second heat treatment from the range of 500 C to 10 〇〇ec, and the temperature is raised at a rate of 0.1 to 5.0 ° C /min. It is carried out within the range of 1 to 96 hours. The invention of Patent Application No. 6 is related to the manufacturing method of Patent Application No. 4, and the third heat treatment is carried out at a temperature of 0.1 to 20 ° C / minute from a range of 900 ° C to 1250 ° C or a full range. 1 to 96 hours of the range • Performed within the perimeter. * The invention of claim 7 is as shown in FIG. 1(e) or FIG. 2(f), and the simOX substrate manufactured by the method of any one of claims 1 to 6 has a buried oxide layer 12, Formed on the surface of the wafer to a predetermined depth; the SOI layer 13' is formed on the surface of the wafer on the buried oxide layer 1; the defect layer 14a' is formed under the buried oxide layer π; and the surface layer 14' is in the buried oxide layer 12 Below. The body layer 14 below the defect layer has a gettering source formed by the oxygen deposit i4c. The density of the oxygen deposit 14c is lx 108~lx 1012/cm3, and the size of the oxygen deposit 14c is 50 nm or more. SIMOX substrate. In the invention related to Patent Item 7, the body layer 14 below the defective layer 14a has a gettering source formed by the oxygen deposit 14c, and the density of the oxygen deposit 14c is lx 1 〇 8 〜 lx 1012 / cm 3 The size of the oxygen deposit 14c is 5 〇 nm or more and thus becomes a gettering source of a strong defect layer of 8 12 ^ 33257. If most of the heavy metal contaminants previously intercepted by the defect layer 14a can be deposited by the oxygen layer of the body layer 14 The object 14c is aspirated. Effect of the SIMOX substrate of the present invention is a gettering source formed by oxygenated deposits on the surface layer below the defect layer, and the density of the oxygen deposit is 1 X 108~lx 1012/cm3, oxygen deposit The size is 5 〇 nm or more and becomes a stronger source of suction than the defect layer, so that the heavy metal intercept concentration of the defect layer can be reduced, and heavy metal can be effectively worn inside the body layer. [Embodiment] The best mode for carrying out the invention will be described based on the drawings. The invention relates to a SIMOX substrate manufacturing method, which is characterized in that after the oxygen ions are implanted in the germanium wafer, the surface of the wafer is formed into a buried oxide layer by a heat treatment to form a buried oxide layer on the surface of the wafer, and a layer is formed on the surface of the wafer. As shown in Fig. 1, in the SIM0X substrate manufacturing method of the present invention, the tantalum wafer 11 after the implantation of oxygen ions is subjected to a three-stage heat treatment, and then the oxide films 11b and 11c formed on the surface of the tantalum wafer 11 are removed. The steps are as follows: (1) Oxygen ion implantation step First, as shown in Fig. 1(a), a tantalum wafer 11 is prepared, and oxygen ions are implanted into the tantalum wafer n. The prepared wafer 11 is provided with 1 〇丨7~丨8χ 1018at_s/cm3 (old ASTM) oxygen concentration. This wafer can be either epitaxial wafer or annealed wafer. Therefore, the gas ion is implanted inside the prepared wafer U. The oxygen 8 13 1333257 ion implantation system is the same as the conventional method. Thus, the thickness of the SOI layer 13 of the last available SIMOX substrate is 1 〇 2 2 〇〇 nm, preferably 20 〜 100 rnrn, from the wafer. 11 surface implanted oxygen ions to the specified depth field 11a. The thickness of the SOI layer 13 is less than i〇nm to control sqi The thickness of the layer 13 is difficult. When the thickness of the SOI layer 13 exceeds 2 〇〇 nm, it is difficult to implant oxygen ions at the acceleration voltage. (1-2) The first heat treatment step is as shown in Fig. 1(b). The wafer implanted with oxygen ions is subjected to a first heat treatment at a temperature of 1300 to 1390 ° C in a mixed gas atmosphere of oxygen and a non-active gas. The inert gas is argon, nitrogen gas, etc. The gas atmosphere of the first heat treatment is a mixed gas of oxygen and argon, or a mixed gas of oxygen and nitrogen, and the heat treatment time of the first heat treatment is 1 to 20 hours, preferably 10 to 20 hours. 1 heat treatment, the oxide film lib, 11c' is formed on the surface and the back surface of the germanium wafer 11 from the surface of the wafer 11 to a predetermined depth. The buried oxide layer 12 is formed on the entire or a part of the wafer. The oxide film lib and the buried surface are further buried. The SOI layer 13 is formed between the oxide layers π. Further, the defect layer Ma is formed directly under the buried oxide layer 12. (1-3) The second heat treatment step is followed by the first heat treatment as shown in Fig. 1(c). Shixi wafer η leaves the state of oxide film lib, 11c, or removes the state of bismuth film lib, 11c 'The second heat treatment is performed in a mixed gas atmosphere of oxygen, nitrogen, atmosphere, hydrogen or the like. The state of the oxide films ub and 11c is left, and when the second heat treatment is performed, the SOI is not caused particularly in a non-oxidizing gas atmosphere. Layer 13 14 : for this reason, 'the first is to increase and grow, and when the first heat treatment, the oxide film llb'llc will be more second surface, the first thickness in the hydrogen or the atmosphere ί ' The reduction of the thickness of the coffee layer U can still be performed under the prescribed state of the first %1?1, which can be removed in the oxide film llb, llc &lt; argon or = oxygen; the second heat treatment gas atmosphere is nitrogen, 1, and then, the condition of the second treatment is 400 to the temperature of the assignment, because the heat treatment temperature of αΛ is set to 400 to 90 (the heat of the rc is low, and the second rail is required for a long time. Treatment _ J ^ can not form an oxygen deposition nucleus. Further, the lower limit 佶fli, H time is in the range of 96 hours, because when the temperature is less than 値, the time for forming the oxygen deposition nucleus is too short and exceeds the upper limit. (: Geng push) Reduce the problem. This second heat treatment can be better with 5〇〇~8〇〇~3i hours. Also 'this second heat treatment in /八之# / part Fanyuan or all Fanyuan It is also possible to carry out the range of G.1~5.0.0 咕 preferably 疋4~35 hours. The lower part of iV is hoter than the defect below the buried oxide layer 12; the third hot spot of layer 2 : The layer is widely formed as the first heat treatment, and the second heat treatment is performed on the tantalum wafer n after the second heat treatment. The third heat treatment is in the case of oxygen, nitrogen, argon, hydrogen or its 15 1333 257 atmosphere at a temperature lower than the second heat treatment temperature of _~%. The gas atmosphere of the third heat treatment is preferably a nitrogen-nitrogen emulsion, a neon or a nitrogen gas or an argon gas. = degree is specified in the range of 9GG~125Gt, because it is not enough to grow enough, and when it exceeds the upper limit, oxygenation will occur.

Question. Further, the third heat treatment time of the mosquito is 1 to % small because the growth of the oxygen deposit is insufficient when the lower limit is less than ’, and the productivity is lowered when the upper limit is exceeded. It is more preferable that the third heat treatment can be carried out at a temperature of 1000 to 12 Torr for 8 to 24 hours. Further, the third heat treatment is in the range of 9003⁄4 to i25〇°c or all ranges '0.1 to 20'. . / The speed of the minute, it is best to maintain the temperature of the hole / minute to maintain 1 to 96 hours, preferably within the range of 8 to 24 hours. By performing this third heat treatment, the oxygen deposition core 14b formed on the surface layer of the body layer can be grown into the oxygen deposit Me. (1·5) Removal Process of Oxide Films lib and 11c Finally, as shown in Fig. 1(e), the oxide film lib and Ue formed on the surface of the wafer U after the third heat treatment are removed by hydrofluoric acid or the like. The SIMGX substrate obtained by the present invention comprises: a buried oxide layer 12 working on the surface of the wafer from the surface of the mosquito; and an SOI layer I3 formed on the surface of the wafer formed on the buried oxide layer, and being formed directly under the buried oxide layer The defect layer 14a and the body layer 14 underlying the oxide layer 12. Self-defective layer

The body layer 14 under Ha has a gettering source formed by the gas deposit 14e, the density of the oxygen deposit 14c is 1χ1〇8~ΐχ ι〇1ζ/cm3, and the size of the oxygen deposit 14c is 5Onm or more. 16 1333257 In this SIMOX substrate, the body layer 14 from the defect layer 14a has an oxygen deposit 14c having a density of lx 1 〇 8 〜 lx 1012 /cm 3 and a size of 5 〇 nm or more, so that the sudden heavy metal in the process of the device Contamination can be effectively captured by the oxygen deposit 14c. Further, the oxygen deposit 14c becomes a strong source of suction than the defective layer 14a, so that heavy metal contaminants which have been trapped in the defect layer 14a in the past can be inhaled by the oxygen deposit 14c of the body layer 14. As a result, for example, the heavy metal concentration is forced to be a heavy metal concentration at lx 1011 to lx 1012 /cm2 to become the substrate defect layer 14a. The heavy metal concentration intercepted by the substrate is reduced to a level of 5 x 109 / cm2. However, the SIMOX substrate forming part of the buried oxide layer can also be applied. Field Next, the second preferred embodiment of the present invention will be described based on the drawings. The present invention relates to a SIM〇x substrate in which a silicon oxide is implanted inside a germanium wafer and a heat treatment is performed to form a buried oxide layer from the surface to a predetermined depth, and a SOI layer is formed on the surface of the wafer. Therefore, as shown in FIG. 2, the method for fabricating the SIM〇x substrate of the present invention is to perform a three-stage or four-stage heat treatment after the implantation of oxygen ions, followed by removal of the germanium wafer. 11 surface oxide film llb, 11c. The following are the various processes. (2-1) Oxygen ion implantation process First, as shown in Fig. 2(a), a germanium wafer u is prepared for twinning

11 For this wafer, mashed wafer 11 is % 1333257. This gas pair is prepared with such crystal K 11 (four) implanted oxygen ions. This oxygen ion implanted the __, 801 layer 13 has a thickness of 1 ():. 5= Please implant the oxygen ions on the surface of the material 11 to the specified depth = ^. When the thickness of S〇M 13 is less than 1〇nm, it is necessary to control the 〇〇i layer to ··?: It is difficult, and if the thickness of the S〇1 layer 13 exceeds the fineness (10), the oxygen ion implanter has difficulty in accelerating voltage. . On the surface of the dream wafer 11, the skirt is partially masked and then placed inside the Shi Xijing 11 11 . Oxygen ions are implanted under the unmasked portion to the inside of the wafer, below the masked portion. Oxygen ions cannot be implanted into the interior of the wafer, and therefore, a subsequent second heat treatment is performed to form a partial buried oxide 2 only under the unmasked portion. (2-2) First heat treatment step As shown in Fig. 2(b), the wafer u to which oxygen ions are implanted is in a mixed gas atmosphere of oxygen and an inert gas at 13 〇〇 to 139 Torr. The first heat treatment is performed at the temperature of the crucible. The inert gas is argon, nitrogen or the like. Therefore, the gas atmosphere of the first heat treatment is preferably a mixed gas of oxygen and argon or a combined gas of oxygen and nitrogen. The heat treatment time of the first heat treatment is 1 to 2 hours, preferably 10 to 20 hours. # Thus, in the first heat treatment, the oxide film lib, 11c' is formed on the surface and the back surface of the germanium wafer 11 from the surface of the wafer 11 to a predetermined depth! The buried oxide layer 12 is formed entirely in the crystal. Further, when oxygen ions are implanted from the surface of the wafer u to a predetermined depth region due to masking or the like, the forming portion buryes the oxide layer 12. Further, a soi layer η is formed between the surface of the germanium film ub and the buried oxide layer between 18 1333257. Further, the defect layer 14a is directly under the buried oxide layer 12. And do * (2·3) rapid heat treatment process. As shown in the figure, the wafer after the first heat treatment is kept at C~l35〇C for 1 second to 9 seconds, and then the temperature is lowered by a temperature of two seconds or more. The gas atmosphere for rapid reduction is preferably a desired atmosphere containing argon or ammonia. Further, the rapid heat treatment conditions are in the range of 1 〇 5 (rc 〜 〇 ( ( : 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急 急In order to promote the formation of oxygen deposition nucleus, and exceed the upper limit == dynamic dislocation, there is a problem in the fabrication of the device, which is not suitable::: 2 is 1100~13〇〇°C. Again, the retention time is 1~900 ^疋Because, when the limit is full, the temperature is in the plane and depth of the wafer; the temperature varies, and the quality is poor. The best time is ίί is to consider the reduction of sliding and productive The optimal holding time is 10~60 seconds. The last time is kept on the wafer, and the neighboring wafers are placed in the wafer. The processing/difficulty cavity is left in the wafer. Planting is the key. The 24 cooling temperature hole disappears when it reaches the surface, and the concentration decreases near the outermost surface. The resulting cavity diffuses outward. _ The inner surface of the ## is too long, and the (4) side diffusion is more than the speed. When the cooling cavity is reduced, the cavity is reduced, and no amount of oxygen is formed. Deposit 1333257 nucleus. Therefore, after the specified hold, 'speed 1 (TC / sec or more to cool down. The specified cooling rate is 10 ° c / sec, because the lower limit 値 can not get the effect of suppressing the void disappear. No upper limit is set 値It is because the effect is almost constant when the temperature exceeds 10 ° C / sec. However, when the cooling rate is set too high, the temperature uniformity of the wafer surface is not good and the sliding occurs during cooling, so the cooling rate is low. It is preferable to control the productivity in the range of 10 to 100 ° C / sec. The cooling rate is better. Due to the rapid heat treatment, the void layer 15 is implanted in the body layer 14 below the buried oxide layer 2, so that the rapid heat treatment can be performed. Ensure that the surface density of the oxygen sink in the wafer surface is evenly distributed, even if the low-oxygen 11 wafer can also improve the authenticity of oxygen deposit growth. Furthermore, if this rapid heat treatment is not applied, it will be followed. The process 'is also difficult to make the oxygen density in the wafer surface uniform. (2-4) In the second heat treatment step, as shown in Fig. 2(d), the rapidly heat-treated tantalum wafer u is oxidized.臈lib, llc state, or remove oxide film Ub, ^2 is treated in a mixed gas atmosphere of oxygen, nitrogen, argon, hydrogen or the like, leaving the state of the oxide film 11b, llc, and performing the second heat, especially in a non-oxidizing gas atmosphere, without causing SOI The second layer: salt 5 or dispersion is preferred. The reason is that the first is the second heat treatment in the oxygen * two atmosphere, the oxide film llb, the m will consume the surface of the crystal 81 dream 'the second is When the first heat treatment is performed in a gas or argon atmosphere, S0II 13 will be turned off. The other side s〇i 8 20 1333257 = when the thickness is thicker, although the thickness of the S0I layer 13 is reduced, the second &lt;S〇1 layer 13' Therefore, it is also possible to remove the oxide film llb and lie into the second heat treatment. This second heat treatment gas nitrogen is preferably added with a small amount of oxygen nitrogen. Μ

s

Further, the second heat treatment condition is 5 〇〇 to 1 〇〇〇 &lt;?c, and the temperature is 1 to 舛 J, and the second heat treatment temperature is 5 〇〇 to 1 〇〇〇. In the range of 〇, when f is less than the lower limit, the formation temperature of the core is too low and it takes a long time to process. In addition, it is stipulated that the heat treatment time of the first and the second is 丨~96 hours, because the time for opening the nucleus is too short when the lower limit is not exceeded, and the productivity is lower when the upper limit is exceeded. . The second heat treatment can be carried out at a temperature of 5 Torr to 8 Torr for 4 to 35 hours. Again, this second reduction is between 5 〇〇 C and 1000. (: one part of the range or all ranges, to 〇 1~5 (speed of rc / minutes 'preferably 0.1~l. (TC / / minutes to maintain the divination hours, preferably within the range of 4 to 35 hours It is also possible to perform the second heat treatment to form the oxygen deposition core 14b on the body layer 14 which is formed below the defect layer 14a directly under the buried oxide layer 12. The SIMOX substrate of the second heat treatment step is completed in the semiconductor. In the heat treatment of the device manufacturing process, the oxygen-deposited core will grow into an oxygen deposit, and the wafer will have an IG effect in its entirety. (2-5) The third heat treatment process is followed by the second heat treatment process, as shown in Fig. 2(e). The third heat treatment is performed by the second heat treatment wafer. The third heat treatment is in a mixed gas atmosphere of oxygen, nitrogen, argon, hydrogen or the like, and is higher than the second heat treatment temperature by 9 〇〇 to 125 〇. 21 1333257 f The temperature is maintained for 1 to 96 hours. The gas atmosphere of the third heat treatment is preferably carried out under a gas atmosphere of nitrogen, argon or a small amount of nitrogen or argon. The third heat treatment temperature is specified as 900~ In the range of 1250X: because there is no oxygen deposit when the lower limit is not reached It is sufficient to grow, and if it exceeds the upper limit, the problem of dissolved oxygen deposits will occur. It is also specified that the third heat treatment is in the range of 1 to 96 hours because the growth of the oxygen deposit Me is insufficient when the lower limit is less than the upper limit. In the case of 値, there is a problem of reduced productivity. In addition, this third heat treatment is preferably performed at 8:24 hrs from 1 °C to 12003⁄4. Further, the third heat treatment is in the range of 900 ° C to 125 〇. Or all ranges, in the range of 0.1 to 20. (: / minute speed, preferably at a temperature of ^ 5 ° C / min and maintained for 1 to 96 hours, preferably within the range of 8 to 24 hours * can also be carried out In the third heat treatment, the oxygen deposition core 14b formed in the gift layer 14 can be grown into the oxygen deposit 14c. '(2-6) oxide film lib, lie removal step shown in Fig. 2 (1), the third heat treatment crystal The oxide film lib and lie formed on the surface and the back surface of the circle u are removed by hydrofluoric acid, etc. It is known that the SIMOX substrate includes a buried oxide layer 12 formed on the surface of the wafer at a predetermined depth and field, and is formed in the buried layer. The SOI layer 13' on the surface of the wafer on the oxide layer is formed directly under the buried oxide layer 12 The defect layer 14a; and the body layer 14 under the buried oxide layer 12. The body layer 14 from the defect layer 14a has a density of the getter source 'oxygen deposit 14c formed by the oxygen deposit i4c ΐχ 1〇8 ~ ix if / em3, oxygen deposit 14c size is 50nm or more" This SIM0X substrate 'from the defect layer i4a below the body layer 22 1333257 M - has a density lx ι〇8~ΐχ ίο12 / cm3, size 50nm The above oxygen deposit He, and thus the sudden heavy metal contamination during the process, can be effectively captured by the oxygen deposit Mc. Further, the oxygen deposit 14c is a strong source of suction compared to the defect layer 14a, so that heavy metal contaminants intercepted in the defect layer 14a in the past can be inhaled by the oxygen deposit 14c of the body layer 14. As a result, for example, when the heavy metal concentration is 1X 1011 to lx 1012 /cm2 as a substrate by forced deposition of heavy metals, the concentration of heavy metals intercepted by the defect cluster 14a is reduced to 5 χ 1 〇 9 / cm 2 or less.

Implementation of Your J « k The following describes an embodiment of the invention in conjunction with a comparative example. <Example 1> First, as shown in Fig. 1(a), an oxygen concentration of 1.3X 1 〇 18 atoms/cm 3 (old ASTM) and a resistivity of 2 〇 Q · (10) cultured by the cz method were prepared. C thickness of CZ Shi Xi wafer. Next, the wafer is heated to 55 〇 ° C, in which state oxygen ions are implanted under the following conditions for a prescribed area of the wafer (for example, from the surface of the substrate _ to about 0.4 / / m). Acceleration voltage: 180 keV Beam current: 50 mA Dosage: 4 x 1017 /cm2 After ion implantation, SC-1 and Sc_2 washing are performed on the wafer surface. Then, as shown in FIG. 1(b), the wafer 11 is placed in a heat treatment furnace in an argon gas atmosphere of a partial pressure of oxygen/5/, and maintained at a constant temperature of 1350 C for 4 hours, and then the gas in the furnace is continued. The oxygen compartment is increased to one of the first heat treatment steps for further maintenance of 4 23 1333257 hours. The wafer in which the i-th heat treatment is completed will be as shown in Fig. (10), leaving the surface of the oxide film 11b, llc in a state of 1 ° c to 850 ° C in a 1% oxygen atmosphere. After the continuous heating of 〇/min, the second heat treatment was maintained at 850 C for i hours. This second heat-treated wafer 11 was heated to 1,100 at a temperature increase rate of 5.0 C/min from 850 C in a 1% oxygen atmosphere as shown in Fig. 1(d). After the crucible, a third heat treatment was carried out at 1100 ° C for 8 hours. Then, the surface of the wafer subjected to the third heat treatment step was cooled to a temperature of 3 〇〇c/min to a temperature of 700 C. The oxide film ub, llc of the wafer surface and the back surface of the heat-treated wafer is removed by HF solution as shown in Fig. 3 (the SIM之x substrate of the phantom. This SIM〇x / substrate is used as the embodiment 1. - <Example 2> 'As shown in Fig. 1(a), the oxygen concentration prepared by CZ method is 1.4xl〇18atoms/cm3 (old ASTM), nitrogen concentration 4 〇χ 1〇丨4at〇ms /cm3 (old ASTM) and resistivity ι 〇Ω · cm 夕 夕 ingot cut out the CZ shredded wafer of the specified thickness. Then 'heat this wafer to the specified area of the Shixi wafer in this state (for example, about 0.4 // m from the surface of the substrate) Oxygen ions were implanted under the following conditions: Accelerating voltage: 180 keV Beam current: 50 mA Dose: 4 x 1 〇 17 cells/cm 2 After the ion implantation, the wafer surface was subjected to SC-1 and sC-2 washing. As shown in Fig. 1(b), the wafer is placed in a heat treatment furnace under an argon gas atmosphere with a partial pressure of oxygen of 0.5%, and maintained at a constant temperature of 135 ° C for 24 hours, and then continued for 4 hours. The first partial heat treatment is carried out by increasing the partial pressure of oxygen in the furnace atmosphere to 7〇% for 4 hours. The wafer after the completion of the heat treatment will leave the surface oxygen as shown in Fig. 1(c). The state of bismuth Ub and Uc is 6 〇〇 in the 1% oxygen (mouse-based) gas condition. 匸 to 70 (1. After the factory LV Ω / min continues to heat up, then keep the job small: 2 0 heat? : The second heat-treated Shi Xi wafer 11' is heated from 7 (8) C at a rate of 5.0 C/min to 1 〇〇〇 in a 1% oxygen-rolling atmosphere as shown in Fig. 1(d). Thereafter, a third heat treatment is performed for 10 hours at 10 (8) c. After the φ, the surface of the wafer subjected to the third heat treatment is cooled to a temperature of 700 C at a temperature drop of 3. 〇, /, and the surface of the wafer after heat treatment is completed. Oxidation, the films Ub and llc were removed by HF solution to obtain a SIM〇x substrate. This Sim〇X • substrate was used as Example 2. <Example 3> Example 2 was carried out except that the second heat treatment was maintained at 700 C for 4 hours. The SIMOX substrate was obtained in the same manner. This SIM〇x substrate was used as Example 3 ° <Example 4>. The second heat treatment was held at 700 ° C for 8 hours, and the SIMOX substrate was obtained in the same manner as in Example 2. This SIMOX substrate was used as the SIMOX substrate. Example 4 <Example 5> First, as shown in Fig. 1 (a), an oxygen concentration of 1.4 x 1018 atoms/cm3 (old ASTM) and a carbon concentration of 2. 02x 10,6 atoms/cm3 (old ASTM), and a resistivity of 1 〇Ω · cm. The bismuth ingot cuts out the CZ 矽 wafer of the specified thickness. On the surface of the CZ 矽 wafer, 3 矽 矽 1333257 crystal stupid gland is deposited. Secondly, The wafer was heated to 550 ° C, in which state oxygen ions were implanted in a prescribed area of the wafer (for example, from the surface of the substrate to a region of about 0.4 / zm) under the following conditions. Acceleration voltage: 180 keV Beam current: 50 mA Dosage: 4 x 1017 cells/cm2 • SC-1 and SC-2 washes are performed on the wafer surface after ion implantation. Then, as shown in Figure Ub), the wafer 11 is placed in a heat treatment furnace. Under an argon gas atmosphere with a partial pressure of oxygen of 0.5%, the temperature is maintained at a constant temperature of 1350 4 for 4 hours. The oxygen partial pressure is increased to 70%. The first heat treatment is performed for 4 hours. The wafer after the first heat treatment is completed. • The state of the oxide film lib and 11c on the surface is left as shown in Fig. 1(C). The second heat treatment was carried out at 700 ° C for 8 hours in a nitrogen atmosphere. The second heat-treated tantalum wafer is heated in a nitrogen atmosphere as shown in FIG. 1(d) from 700 ° C at a temperature increase rate of 5.0 ° C / minute to 10 ° C, and then carried out. The third heat treatment was maintained at 1000 ° C for 16 hours. The surface of the third heat-treated wafer was then 3.0. (: / sub-cooling speed drop • Lu Wen to 700. (: The oxide film lib, 11c on the surface and back of the finished heat-treated wafer is removed with HF solution to obtain a SIMOX substrate. This SIMOX substrate is used as Example 5. Example 1> A SIMOX substrate was obtained in the same manner as in Example 1 except that the second heat treatment and the third heat treatment were not performed. This SIMOX substrate was used as Comparative Example 1. 26 1333257 <Comparative Example 2> Instead of the second heat treatment and the third heat treatment, the implementation was carried out. The heat treatment was started at 500 ° C and the final temperature was 850 ° C, and the temperature was continuously increased by 1. ° ° C / min. The SIMOX substrate obtained in the same manner as in Example 1 was used. This SIMOX substrate was used as Comparative Example 2. Test 1> After removing the surface oxide films lib and 11c from the SIMOX substrates 10 of Examples 1 to 5 and Comparative Examples 1 and 2, the SOI layer 13, the buried oxide layer 12, and the buried oxide layer of each SIMOX substrate were positive. The underlying defect layer 14a is separately dissolved and recovered by aqueous solution of hydrofluoric acid nitric acid, and the recovered solution is subjected to ICP-MS measurement (Inductively Coupled Plasma)

Mss Spectrometry Inductive Plasma Mass Analysis) measured the iron, nickel, zinc and equivalent heavy metals contained in the solution. Further, the body layers 14 of Examples 1 to 5 and Comparative Examples 1 and 2 were all dissolved, and the concentration of heavy metals in total dissolution was measured. The heavy metals other than nickel, i.e., iron, zinc, and copper, were not observed in combination with the SOI layer, the buried oxide layer, the defect cluster layer, and the surface layer of the SIMOX substrates of Examples 1 to 5 and Comparative Examples 1, 2. The nickel concentration results of the respective layers of the SIMOX substrates of Examples i to 5 and Comparative Examples 1 and 2 are shown in Table 1. 27 1333257 Table 1 Recording concentration [atoms/cm2] atoms/cm SOI layer buried oxide layer defect cluster layer body layer Example 1 Example 2 &lt;5.0x 1〇9 &lt;5.0χ &lt;5.0χ 109 &lt;5.0χ ΙΟ9 2.6χ 10π 4.8χ ΙΟ11 &lt;5.0χ ΙΟ9 &lt;5·0χ ΙΟ9 Example 3 &lt;5.0χ 1〇9 &lt;5.0χ ΙΟ9 &lt;5·0χ ΙΟ9 Example 4 &lt;5.0χ 1〇9 &lt 5.0χ ΙΟ9 &lt;5.0χ 109 Example 5 Comparative Example 1 Comparative Example 2 &lt;5.0χ 1〇9 &lt;5.0χ ΙΟ9 &lt;5.0χ ΙΟ9 5.0χ ΙΟ10 5.0χ 1〇'° 5.0χ ΙΟ10 &lt;1.0 χ 10η 5.0x10^^ 5.0χ ΙΟ10 5·0χ ΙΟ10 &lt;1.0χ 10η It can be seen from Table 1 that the SIM〇x substrate, the SOI layer, the buried oxide layer and the defect cluster layer of Comparative Examples 1 and 2 were observed, respectively. The surface concentration is converted to nickel of about 5.0 x 10 atoms/cm2. The other side has a nickel concentration in the body layer below the detection limit. On the other hand, the concentration of nickel in the SOI layer, the buried oxide layer and the defect layer of the SIM〇x substrate of Examples 1 to 5 is below the detection limit 値. Further, the concentration of nickel in the body layer is 2·6 χ 1011 to 4.8 X 10 uat 〇 /cm 3 , that is, the oxygen deposit formed in the body layer reliably inhales the heavy metal impurities. Lu <Comparative Test 2> The SIMOX substrates of Examples 1 to 5 and Comparative Examples 1 and 2 were separated by two divisions. The two sides of the split substrate are selectively etched by Wright Money. First, the substrate of one of the substrates was observed by an optical microscope, and the density of the oxygen deposit was measured from the depth of the surface of the substrate. The SIMOX substrate of Comparative Examples 1 and 2 had an oxygen deposit density of 5 X 107 /cm 2 or less. The other side of the SIMOX substrate of Examples 1 to 5, 28 1333257, has an oxygen deposit density in the range of lx 108 〜 l 〇 12 / cm 3 . Further, a DZ layer of the oxygen-free deposit 14c exists in the field of 10/zm directly below the buried oxide layer. Next, the other substrate was observed by an electron microscope to determine the size of the oxygen deposit. The SIMOX substrates of Examples 1 and 2 had an oxygen deposit size of 50 nm or less, but the SIMOX substrates of Examples 1 to 5 had a large oxygen oxide size of 50 nm or more. <Comparative Test 3> A part of the sample obtained in Example 5 was measured by a FT-IR (Fourier transform infrared absorption spectroscopy) apparatus to obtain a residual oxygen concentration after heat treatment, and the residual oxygen concentration was 5 x 1017 atoms/cm3, and there was no oxygen deposition. The amount of bending before and after the material growth heat treatment process. <Example 6> First, as shown in Fig. 2(a), a CZ twin crystal having a predetermined thickness was prepared by a CZ square culture oxygen concentration ί ο X 10 atorns/cm3 (ASTM) and a specific resistance of 20 Ώ · cm. circle. Next, the wafer is heated to 55 〇. (;, In this state, oxygen ions are implanted in the specified area of the dream wafer (for example, from the surface of the substrate to the field of about 〇.4 em). Acceleration voltage: 180 keV Beam current: 50 mA Dose: 4 x 1017 /cm2 After ion implantation, SC-1 and SC-2 were washed on the surface of the wafer. Then, as shown in Fig. 2(b), the wafer 11 was placed in a heat treatment furnace with oxygen partial pressure of 29 1333257.

In the 5% argon gas atmosphere, after maintaining at a constant temperature of 1350&lt;ti for 4 hours, the first heat treatment step of continuing the oxygen partial pressure in the furnace atmosphere to 70% was carried out for 4 hours. The wafer in which the first heat treatment is completed will be maintained at a temperature increase rate of 50 ° C / sec to 1150 Torr in an atmosphere containing ammonia gas, as shown in Fig. 2 (C), for 120 seconds, followed by a temperature drop rate of 5 〇 ° c / The second is cooled to a rapid heat treatment of 4003⁄4. This rapidly heat-treated crystal crucible ' is placed in an argon atmosphere in a horizontal batch furnace at 8 Torr as shown in Fig. 2(d), leaving the surface of the oxide film nb, lie. The second heat treatment was carried out for 48 hours at a constant temperature. The oxide film on the surface and the back surface of the second heat-treated shredded wafer was removed with an HF solution to obtain a SIMOX substrate. This SIM0X substrate was taken as Example 6. <Comparative Test 4> The SIMOX substrates of Examples 1 and 6 were split into two. The cleaved substrate was selectively etched by Wright etching solution. Observed by an optical microscope, the oxygen deposits were measured from the surface of the substrate to the depth of the surface to determine the density. The density of the oxygen deposit of the SIM〇x substrate of Example 1 was 1 x 104 / cm 2 or less. The other side of the SIMOX substrate of Example 6 has an oxygen deposit density in the range of 8 χ 1 〇 4 / cm 3 . <Comparative Test 5> After the surface oxide films lib and lie of each of the SIM〇x substrates 10 of Example 6 and Comparative Example 1 were removed, the s〇I layer 13 of each SIM〇x substrate, the buried oxide layer 12, and the buried layer were buried. The defect layer 14a directly under the oxide layer was separately dissolved and recovered as a hydrofluoric acid aqueous solution of nitric acid, and the recovered solution was subjected to ICP-MS measurement to measure the concentration of nickel contained in the solution. Further, 30 I333257 The surface layer 14 of the example 6 and the comparative example i was measured from the body layer 14 of the back surface ι &quot; (7), and the nickel concentration of the full-melting amount was measured from the field of the back surface l/^m. (4) Each 4 (four) is completely dissolved, and the SIMOX substrate of Example 6 is not detected in other fields except for the detection of nickel from the back surface = an example! The SIM〇X substrate detects nickel in the buried oxidized clump layer 14a. It is possible to use the industry in the SIMOX substrate of the present invention. Below the defect layer, there is a density of the oxygen source of the oxygen source formed by the oxygen compound X 10~lx 10 The size of the oxygen deposit is 5 〇 nm so that it can be a strong source of suction, and the concentration of the tongue of the defect layer can be reduced, and the heavy metal can be effectively intercepted inside the body layer. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a first manufacturing method of a SIMOX substrate of the present invention; FIG. 2 is a second manufacturing method of a SIMOX substrate according to the present invention. FIG. 0 [Description of main components] 10 SIMOX substrate 11 矽 Wafer 12 Buried oxide layer 13 SOI layer 14 Body layer 14a Defective layer 14b Oxygen deposition core 14c Oxygen deposit 15 Cavity 31

Claims (1)

Patent application No. 1333257, No. 94,123,983, the revised specification of the unmodified line after the amendment, in the form of a patent application: 1. A method for manufacturing a SIMOX substrate, comprising: implanting oxygen ions inside the germanium wafer 11 An oxygen ion implantation process; and placing the wafer 11 in a mixed gas atmosphere of oxygen and an inert gas, and performing an ith heat treatment at a temperature of 1300 to 1390X: to a predetermined depth below the surface of the wafer 11 Forming a buried oxide layer 12 in the field, and forming a process of s〇i ^ 13 on the surface of the buried oxide layer 12, characterized in that: u the wafer n before the oxygen ion implantation has 8χ1〇η~ Ι8χ 1, 〇at〇ms/cm3 (old ASTM) oxygen concentration, and the buried oxide layer 12 is formed on the wafer in full or partial damage, and includes the following steps: placing the wafer after the first jth heat treatment In an argon gas atmosphere or in a mixed gas atmosphere of oxygen and argon below the enthalpy, one of the range of 4 〇〇 to 9 = = the range or the full range _, the temperature is increased at a rate of sub-fraction and is carried out at a temperature of = heating ~9M, the second heat treatment, and thus the shape f forming the oxygen deposition core 14b in the surface layer 14' below the defect layer 14a directly below the buried oxide layer 12; and the wafer after the second heat treatment is placed in a mixed gas of oxygen and argon, It is one of the range of 900 to 1250 ° C higher than the second heat treatment, and the third heat treatment is performed at a temperature of 1 to 5 t/min and the temperature is increased by the third heat treatment. Compared with the above-mentioned defect cluster layer 14a, the gold MC' uses this oxygen deposit 14c to reduce the occurrence of heavy metal 4, and is trapped by the upper frequency trap layer. The heavy metal 32 is captured by the patent application No. 94123983, and the revised uncorrected specification is amended. The three-concentration 'the process of forming a DZ layer in the lower right side of the buried oxide layer 12 at the same time. 2. The manufacturing method of SIMOX substrate, including: X in the Xixi wafer 11 (4) implanted oxygen ion 3 oxygen ion implantation and 3 it: placed in the mixed gas of the thin (four) body , Yu Li ~ 139 (the temperature of rc under the implementation of the heart treatment = Π 11 surface below the surface of the specified depth of the formation of buried oxide II, m buried oxide layer 12 on the surface of the wafer to form s〇i; 13 process, its characteristics However, the oxygen concentration of the 矽 wafer u having 8 χΐ〇 1 Η) at_/em (old ASTM) is formed in the wafer, and the buried oxide layer 12 is formed on the wafer. The following steps are as follows: 乂° [The wafer after the first heat treatment is placed in 1G50~1350 for 900 seconds, followed by heat treatment at a temperature drop rate of 耽/sec, j/sec, and under the above buried oxide layer 12. The step of implanting the body layer 14 into the void; and placing the wafer after the heat treatment of the upper layer in a nitrogen atmosphere or less than 1% of oxygen and a mosquito-mixed atmosphere towel on the lion-face. In the range of C-partial range or in the whole range, the second heat treatment in 1 to 96 hours (4) is performed at a temperature of (1) Bucheng/min, and is formed under the defect layer Ma directly under the buried oxide layer 12 The surface layer 14 is formed to form a rolled deposition core i4b; and 33 1333257 Patent Application No. 94123983 is supplemented, and there is no scribe line after correction. Correction page is in triplicate ^ ^ Place the wafer after the second heat treatment described above In a mixed gas atmosphere of oxygen and argon, it is 9 〇〇 to 125 高 higher than the second heat treatment. One part of the = = range or the whole range, the temperature is raised at a speed of 乞 乞 乞 分 并 and the third heat treatment is performed at a temperature of the liter of 1 to 96 hours, and the oxygen deposition nucleus formed on the surface layer 14 is formed. The 14b grows into an oxygen deposit 14c which is stronger than the above-described defect cluster layer 14a, and the oxygen deposit 14c is used to reduce the concentration of heavy gold which can be trapped by the defect cluster layer 14a when heavy metal contamination occurs. 34