JP3210369B2 - Semiconductor device manufacturing method and semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufacturing method capable of efficiently terminating dangling bonds at an interface formed between an insulating film and a semiconductor substrate surface, and a semiconductor device having a small number of dangling bonds at an interface. .

[0002]

2. Description of the Related Art As a method of terminating dangling bonds at an interface formed from an insulating film and the surface of a semiconductor substrate, there have been known methods of terminating the method.
A method of performing heat treatment in an electric furnace in a 100% hydrogen atmosphere at a temperature of 400 ° C. or higher has been adopted. In this case, when the semiconductor substrate is inserted into the furnace and taken out of the furnace, the atmosphere in the furnace is replaced with nitrogen or the like from the viewpoint of safety. Also, “Time Resolved An” by BJFishbein and others
nealing of Interface Traps in Polysilicon Gate Met
al-Oxide-Silicon Capacitors "(J. Electrochem.So
c., Vol. 134, No. 3, pp. 674-681 (1987)), in the termination method using a short-time heat treatment apparatus by lamp heating, an atmosphere in which hydrogen is diluted with nitrogen or the like (forming gas ) The heat treatment was performed at a temperature of 400 ° C. or higher. The reason for using the forming gas is to ensure safety. Also, “Improvement of SiO ₂ / Si” by K. Ohyu et al.
Interface Properties Utilising FluorineIon Implan
tation and Drive-in Diffusion ”(Japan J.Appl.Ph
ys., Vol. 28, No. 6, pp. 1041-1045 (1989)), a method of introducing fluorine at a temperature of 900 ° C. or more and terminating dangling bonds at the interface with fluorine is also used. I was

Further, as described in JP-A-57-160124, as a method for terminating Si dangling bonds in silicon (Si), a hydrogen plasma treatment step at 400 ° C. or higher and a hydrogen plasma There is a method in which a step of gradually cooling to a temperature of 300 ° C. or lower is combined. In this method,
In a hydrogen plasma treatment process at 400 ° C or higher, although the amount of introduced hydrogen increases, the bond between Si and hydrogen is broken,
Unbonded hands cannot be terminated well. Therefore, following this step, it is necessary to slowly cool the introduced hydrogen to form a stable bond with Si (to 300 ° C. or lower) and terminate the dangling bonds with hydrogen. In addition, JP-A-60-1869
And Japanese Patent Application Laid-Open No. Sho 60-16462 disclose high-temperature hydrogen heat treatment.
After a short time heat treatment with nitrogen or hydrogen, and silicon substrate
It is described that the interface with SiO ₂ is chemically stabilized.
Have been. In addition, Japanese Patent Application Laid-Open No.
Hydrogen heat treatment at low temperature
It is described that the surface state density is reduced. Also,
JP-A 62-196870 discloses that after hydrogen heat treatment at high temperature,
Heat treatment at low temperature in an inert atmosphere to remove dangling bonds at the interface
It is described that hydrogen is bonded with a strong bonding force.
Incidentally, JP-A-63-44731 discloses that high-temperature hydrogen
After cooling, the atmosphere is replaced with an inert gas atmosphere,
It is described that hydrogen is bonded to a dangling bond of a con atom.
ing. However, in any known example, the halogen element
Termination at low temperature after hydrogen termination
Is not described. Therefore, in these known examples, the interface stress
The effect of alleviating is not obtained.

[0004]

In a conventional hydrogen termination using an electric furnace, since the atmosphere does not contain hydrogen when the semiconductor substrate is pulled out of the furnace, the hydrogen termination effect is reduced. There was a problem. This problem can be avoided by hydrogen termination using the above short-time heat treatment apparatus. That is, in the short-time heat treatment apparatus, the semiconductor substrate is kept in the forming gas atmosphere even during cooling. However, in the termination at a temperature of 400 ° C. or higher as in this case, the hydrogen termination reaction proceeds, but the hydrogen elimination reaction also increases, so that the dangling bonds at the interface could not be completely terminated. For example, in the above method, about 5 × 10 ¹⁰ dangling bonds can be terminated per area of 1 cm ² ,
About 1 × 10 ¹⁰ unbonded bonds remain, resulting in a termination efficiency of 80%
The result is only about. Further, if hydrogen termination is performed at a low temperature in order to reduce the hydrogen desorption reaction, the amount of hydrogen diffusion to the interface decreases, and it becomes impossible to obtain a sufficient termination effect.

On the other hand, in the termination by introducing fluorine at a temperature of 900 ° C. or more, about 1 × 10 ¹¹ dangling bonds can be terminated per cm ² , so that the number of unterminated dangling bonds is reduced to about 1 × 10 ^9. Although the termination efficiency is close to 100%, not all dangling bonds can be terminated. In this case, the effect of the introduction of fluorine is that the hydrogen elimination reaction from the interface is increased, and the dangling bonds after hydrogen elimination are terminated by fluorine. Then, there is a problem that the film quality of the insulating film is deteriorated. Therefore, the limit of the termination by the introduction of fluorine is substantially limited to about 5 × 10 ⁹ dangling bonds.

Further, in the method of increasing the amount of introduced hydrogen at a temperature of 400 ° C. or more and gradually cooling until hydrogen forms a stable bond with Si, heat treatment in the optimum temperature range of hydrogen termination that passes during slow cooling is performed. Sufficient termination cannot be performed with good controllability. Further, if the slow cooling rate is reduced in order to sufficiently perform the termination in the above-mentioned optimum temperature region, the heat treatment time in other temperature regions becomes longer, and the heat treatment time not contributing to the termination becomes longer. is there. Even if such a method is actually applied to the hydrogen annealing of the insulating film / semiconductor substrate interface, although the termination efficiency is slightly improved, about 1 × 10 ¹⁰ dangling bonds per cm ² remain. When such a slow cooling method is used for the termination of the interface dangling hands, the temperature before annealing is lower than 400 ° C., the termination efficiency is better, and the dangling bonds can be reduced to about 5 × 10 ^9. . Therefore, the termination mechanism is different between the Si dangling bonds in Si and the dangling bonds at the insulating film / semiconductor substrate interface, and the interface dangling bonds are efficiently used by using the method described in JP-A-57-160124. It cannot be terminated. In addition, this method has a limitation that the heat treatment step at 400 ° C. or higher and the slow cooling step need to be a continuous step.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a method of manufacturing a semiconductor device capable of efficiently terminating dangling bonds at an interface between an insulating film and a semiconductor substrate surface. Another object of the present invention is to provide a semiconductor device having a small number of unbonded interfaces.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to terminate a dangling bond at an interface between an insulating film and a semiconductor substrate by terminating a dangling bond including interfacial stress relaxation and hydrogen desorption reaction. A two-stage process of a first termination process and a second termination process of terminating unbonded bonds left in the first termination process in a state where there is little change in interfacial stress and hydrogen elimination reaction. Can be achieved.

Here, the first termination step is to introduce a halogen for a long time at a high temperature by impurity implantation and thermal diffusion to make the halogen 900-1.
Heat treatment at 000 ° C. and a second termination step include low-temperature hydrogen annealing of less than 400 ° C. for cooling in hydrogen or low-temperature annealing of less than 400 ° C. with a large amount of hydrogen contained in the semiconductor device. process and child and the desirability <br/> physician consisting of either.

The first terminating step comprises introducing a halogen element at a high temperature, and the ratio of the number of atoms terminating dangling bonds at the interface is 1 hydrogen atom to 1 halogen atom.
By providing a semiconductor device having an interface with a ratio of 100, a semiconductor device with few interface dangling bonds can be obtained.

[0011]

[Function] If a hydrogen annealing method at a high temperature of 400 ° C. or more is used to terminate dangling bonds at the interface between the insulating film and the semiconductor substrate, a large amount of hydrogen is supplied to the interface, and the interface stress is reduced and the The bond is terminated. For example, in the case of the interface between the Si oxide film and the Si substrate, where the network of the bond between Si and oxygen is small and the bond is weak, the bond is replaced by the bond between Si and hydrogen, and the bond between Si and oxygen is The weaker parts are reduced and the network of the bond becomes larger. That is,
Since the network of the bond between Si and oxygen becomes larger, the stress at the interface is reduced. However, in the annealing at a high temperature as in this method, most of the dangling bonds can be terminated, but the ratio of the elimination reaction to the termination reaction cannot be neglected due to the hydrogen elimination reaction. Therefore,
Unbonded bonds remain due to the contribution of the hydrogen elimination reaction. Normal,
Interface between insulating film and semiconductor substrate, for example, Si oxide film and Si
At the interface with the substrate, about 5 × 10 ¹⁰ to 1 × 10 ¹¹ / cm ² of dangling bonds exist, but in the case described above, about 2 × 10 ¹⁰ / cm ² of dangling bonds remain.

Next, consider the case where the termination of dangling bonds at the interface is performed by introducing a halogen element. For example, when a halogen element is introduced into the above-described interface, the weak bond between Si and oxygen is replaced by a bond between Si and the halogen element, as in the case of the above-described hydrogen introduction, so that the interfacial stress is relaxed and the Si unbonded bond is reduced. Is terminated with a halogen element. However, if a large amount of halogen element is introduced, the quality of the insulating film deteriorates.
Extremely large amounts of halogen elements cannot be introduced.
As a result, about 5 × 10 ⁹ / cm ² of dangling bonds of Si remain.

[0013] In the above two termination methods, 40-95% of dangling bonds can be terminated while relaxing the interfacial stress, but at the same time, the hydrogen desorption reaction proceeds and the quality of the insulating film deteriorates. In addition, complete termination is not possible.

On the other hand, low temperature (less than 400 ° C.) for cooling in hydrogen
In the hydrogen annealing method, desorption of hydrogen during cooling can be avoided, but the terminal efficiency is low because the amount of hydrogen diffusion to the interface is small. In addition, only in such a low-temperature annealing method, there is a slight change in stress, so that the termination efficiency is reduced by the amount of time spent for the change in stress.

Therefore, it is difficult to completely terminate a large number of unjoined hands as described above only by applying these methods alone.

On the other hand, in the case of the method of the present invention,
By performing the first termination step in Ha androgenic element introduction method at high temperatures, it will be the interfacial stress relief and dangling bonds terminated in most low-temperature hydrogen annealing cooling the second end process in hydrogen By terminating dangling bonds left without a change in interfacial stress by a method or a low-temperature annealing method in which excessive hydrogen is contained in a semiconductor device, dangling bonds can be extremely reduced. That is, the influence of the hydrogen elimination reaction, which is a problem in the first termination step, can be compensated for by suppressing the hydrogen elimination reaction by lowering the temperature in the second termination step. In addition, a decrease in the termination efficiency due to a decrease in the amount of hydrogen diffusion to the interface, which is a problem in the second termination step, can be compensated for by the first termination step having a high termination efficiency. Further, from the viewpoint of interface stress, since the stress is relaxed in the first termination step, the change in stress in the second termination step can be ignored. Can be eliminated. In other words, by making the termination process into the two stages described above, the problem of the first termination process is reduced by the advantage of the second termination process, and the problem of the second termination process is reduced by the advantage of the first termination process. Can be complemented. In that sense, the method of the present invention can be called a complementary termination method. If the order of these termination steps is reversed, only the effect of the final termination step can be obtained. Therefore, the termination effect is not obtained by a simple sum of the first termination step and the second termination step.

Now, in either the first termination step or the second termination step, if only one termination step is performed, a difference occurs in termination efficiency due to interface characteristics before termination. This is caused by a difference in plane orientation of the interface before termination and a difference in stress caused by the structure. In the case of the method of the present invention, the level density of interfaces having various structures and characteristics can be reduced to a certain extent, although there is a difference of about twice at the maximum by the first termination step. It can be said that the interface characteristics before the second termination step are almost the same. Therefore, by adding the second termination step to the first termination step, the difference in termination efficiency as described above can be ignored. As described above, in the method of the present invention, the second termination step can be performed only in the temperature region where the termination efficiency is high, so that the controllability of the termination efficiency is improved, and the waste in the case of using the slow cooling step is reduced. A long heat treatment time can be eliminated.

In the semiconductor device, the first terminating step is performed by introducing a halogen element at a high temperature, and in the second terminating step, the ratio of the number of atoms terminating dangling bonds at the interface is 1 hydrogen atom to halogen atom. The reason why the semiconductor device has an interface having a ratio in the range of 1 to 100 will be described below.
First, when the number of halogen elements is smaller than the number of hydrogen atoms, many unterminated dangling bonds remain even if terminated by halogen atoms, and hydrogen cannot be completely terminated. In addition, the number of halogen atoms is 10 times the number of hydrogen atoms.
If it becomes 0 times or more, the film quality of the Si oxide film is deteriorated as described above. The above ratio is the same regardless of whether the halogen element is fluorine, chlorine, bromine, or iodine. However, when terminating with an atom having a large mass, it is desirable to reduce the ratio as much as possible. The reason is that the larger the mass of the atom, the larger the radius of the atom, and the smaller the number of atoms, the more easily the quality of the Si oxide film deteriorates.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The semiconductor device manufacturing method and semiconductor device of the present invention will be specifically described below with reference to embodiments.

[0020]

[Embodiment 1] First, the first termination step is a halogen introduction method, and the second termination step is a semiconductor device (MOS diode).
The effect of improving the interface characteristics when a low-temperature annealing method is performed after excessive hydrogen is introduced into the substrate will be described.

FIG. 2 is a cross-sectional view showing a schematic structure of a MOS diode, using a CZ-grown Si substrate 1 having a (100) plane orientation and a surface p-type impurity concentration of 1 × 10 ¹⁶ / cm ^3. LOCOS oxide film 2 for device isolation (film thickness
500 nm) to a gate oxide film 3 (film thickness) by a normal thermal oxidation method.
10 nm), and then the gate electrode 4 was formed by a polycrystalline Si film (thickness: 300 nm). Next, regarding the MOS diode, the termination of the interface between the LOCOS oxide film 2 and the gate oxide film 3 and the Si substrate 1 is set to the first position.
Was performed by introducing fluorine, chlorine, bromine, and iodine by impurity implantation thermal diffusion into the gate electrode 4. At this time, the implantation energy is 30 keV and the implantation amount is 1
× 10 ¹³ / cm ^{2 to} 1 × 10 ¹⁶ / cm ² and 900 ° C to 1000 ° C
Heat treatment was performed for 0 minutes. After that, an interlayer insulating film and electrodes / wirings were formed to complete the MOS diode. Here, hydrogen was introduced so that hydrogen became excessive in the interlayer insulating film and the metal constituting the electrode / wiring. At this time, the introduction of hydrogen was realized by forming under conditions where the hydrogen concentration increased during the growth of the insulating film and the growth of the metal film. Thereafter, low-temperature annealing at 350 ° C. for 30 minutes was performed as a second termination step.

With respect to the MOS diode obtained as described above, the interface state density of the interface 5 between the LOCOS oxide film 2 and the Si substrate 1 and the interface 6 between the gate oxide film 3 and the Si substrate 1 was measured. . When fluorine is used as the halogen element in the above treatment, the number of hydrogen atoms at the interface is 1
FIG. 1 shows the relationship between the ratio of the number of fluorine atoms to the interface surface state density. The interface state without termination processing is 3
It is about × 10 ¹⁰ / cm ^{2 to} 1 × 10 ¹¹ / cm ² , and the interface 5 is more. When this is subjected to a termination treatment, the ratio of fluorine to hydrogen increases, and the interface state 5 has a surface state density as shown in a characteristic 51, and the interface 6 has a surface state density as shown in a characteristic 61. descend. In particular, it can be seen that a sharp decrease is seen from the vicinity where the above ratio exceeds 1, and the termination efficiency is improved. However, the termination efficiency decreases around the above ratio exceeding 100, and a sharp decrease in the termination efficiency is observed particularly in the characteristic 61 of the interface 6. From the results shown in the figure, by selecting the ratio of fluorine to hydrogen to about 50, the conventional interface state density of only hydrogen termination (for example, 1 × 10
^It can be seen that it can be reduced to about 1/50 of about ¹⁰ / cm ² / eV). The characteristics of the interfaces 5 and 6 before the second termination step are as shown in FIGS. 7 and 8, respectively, and the level density differs depending on the interface before the first termination step.
However, the difference could be reduced by adding the second termination step.

The results obtained when chlorine, bromine and iodine were introduced instead of fluorine in the above example are shown in FIGS.
From the results shown in the figure, the termination efficiency is improved for any of the elements. However, the element having a larger atomic radius has a higher minimum interface state density. It can be seen that it occurs at a lower portion of the "ratio of the number of atoms of the element".

[0024]

[Embodiment 2] The effect on the leak current of the junction when the termination is performed in the same first and second termination steps as in the above example will be described.

The structure of the pn junction diode used for the leak current measurement is shown in FIG. 6, and was prepared by the following method. In other words, a CZ-grown Si substrate
After the p-type impurity concentration on the surface is set to 1 × 10 ¹⁶ / cm ³ , the LOCOS oxide film 1 for element isolation is formed by a normal selective oxidation method.
3 (thickness 500 nm), and then arsenic is
The n-type layer 14 was formed by implanting 0 ¹⁵ / cm ² and performing a heat treatment at 950 ° C. for 30 minutes to form a pn junction diode. Thereafter, a first termination step of the interface between the LOCOS oxide film 13 and the Si substrate 12 was performed by ion implantation into the n-type layer 14 and fluorine introduction by thermal diffusion. At this time, the implantation energy is 30 keV, and the implantation amount is 1 × 10 ¹³ / cm ^{2 to} 1 × 10 ¹⁶ / c
m ^2, and heat treatment was further performed at 900 ° C. to 950 ° C. for 10 minutes. The second termination step was the same as that in the first embodiment. The aluminum electrode 15 was formed before the second termination step.

With respect to the junction leakage current, a reverse voltage is applied between the aluminum electrode 15 and the Si substrate 12 so that the depletion layer 16 is bonded at a portion 17 where the depletion layer 16 is in contact with the interface between the LOCOS oxide film 13 and the Si substrate 12. The evaluation was performed by measuring the leak current in the peripheral portion. FIG. 4 shows the results. In the figure, the case of only normal hydrogen introduction (450 ° C, 30 minutes, nitrogen replacement cooling) 18 and
The results were 19 when only fluorine was introduced and 20 when fluorine was introduced 10 times more than hydrogen. From this result, it can be seen that the leakage current at the peripheral portion of the junction can be reduced to 1/2 to 1/3 by terminating with hydrogen and fluorine as compared with other cases. FIG. 5 shows the dependence of the leakage current around the junction on the termination ratio of fluorine to hydrogen when the reverse voltage is 3 V. The figure shows an initial characteristic 21 and a characteristic 22 after avalanche injection is performed around the junction. The avalanche injection was performed by flowing a current of 0.1 mA per 1 cm of the peripheral length of the junction for 100 seconds. From the results in the figure, the initial characteristics 21
Not only that, the characteristic 22 after the application of the electric stress can be improved. In addition, when an electric stress is applied, when the amount of fluorine with respect to hydrogen is too large, the junction leakage current is significantly increased.

As described above, from the viewpoint of the junction leakage current, the optimum addition ratio of the other elements to hydrogen is slightly narrower than that of the interface characteristics. Therefore, although the termination efficiency is slightly reduced, the effect can be substantially maintained by selecting the optimum ratio.

[0028]

Embodiment 3 When the first termination step is performed by annealing in a normal electric furnace and the second termination step is performed by low-temperature hydrogen annealing of hydrogen cooling, dynamic / access /
An example in which the relationship between the information retention time of a memory (DRAM) element and the hydrogen annealing temperature is determined will be described.

First, a DRAM device having the structure shown in FIG. 8 was formed by a normal process. That is, the surface of the Si substrate 23
After setting the p-type impurity concentration to 2 × 10 ¹⁶ / cm ² , the LOCOS oxide film
24 (thickness 400 nm), gate oxide film 25 (thickness 10 nm), gate polycrystalline Si film 26 (thickness 200 nm, high-concentration phosphorus implantation), and then process gate polycrystalline Si film 26 for insulation. After the formation of the film 27, the source / drain n-type diffusion layer 28, the polycrystalline Si film 29 on the charge storage side (thickness: 500 nm, high-concentration phosphorus introduced), the capacitor insulating film 30 (5 nm equivalent to an oxide film), Crystal Si film 31
(Thickness: 200 nm, high-concentration phosphorus introduced), and further, an interlayer insulating film and wiring were formed to form a DRAM. Next, after hydrogen annealing was performed on this element in an electric furnace, hydrogen cooling annealing was performed in a short-time heat treatment apparatus. In this case, hydrogen annealing in an electric furnace is performed for 30 minutes, and
Cooling was done in nitrogen for safety. The hydrogen cooling annealing in the short-time heat treatment apparatus was performed for 2 minutes, and the cooling was performed in hydrogen.

FIG. 7 shows the relationship between the hydrogen annealing temperature and the DRAM element information retention time. From the results shown in the figure, when the information retention time of the sample before the hydrogen annealing in the electric furnace was set to 1, in the sample 32 subjected to the hydrogen annealing in the electric furnace, the lower the temperature, the more the hydrogen termination effect was. At 30%
It can be seen that the holding time becomes longer. However, in this case, the terminal efficiency is low because of nitrogen cooling. Also,
In sample 33 that was subjected to hydrogen cooling annealing with a short-time heat treatment apparatus, the retention time was increased by about 50% at 450 ° C., but at temperatures lower than that, the hydrogen termination effect was low due to the short processing time. . On the other hand, it can be seen that the retention time can be increased to twice or more in the case of the sample 34 in which the hydrogen annealing in the short-time heat treatment apparatus at 400 ° C. or less is performed after the hydrogen annealing in the electric furnace at 410 ° C. This is because most of the interfacial stress relaxation and hydrogen termination are performed by electric furnace hydrogen annealing,
This is because a small amount of the remaining dangling bonds was terminated by hydrogen cooling annealing in the heat treatment apparatus for a short time. Here, the second
By using an electric furnace hydrogen annealing with hydrogen cooling as the termination step, the amount of hydrogen supplied to the interface can be increased, so that the information retention time can be made longer.

[0031]

As has been described above, according to the present invention, by the manufacturing <br/> manufacturing method and a semiconductor device and the method and apparatus of the present invention structure, to solve the problems had in the prior art Thus, a method of manufacturing a semiconductor device capable of efficiently terminating dangling bonds at an interface between an insulating film and the surface of a semiconductor substrate and a semiconductor device with few dangling bonds at an interface can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between the ratio of the number of fluorine atoms to the number of hydrogen atoms at the interface formed from an insulating film and the surface of a semiconductor substrate and the interface state density;

FIG. 2 is a sectional view showing a schematic structure of a MOS diode.

FIG. 3 is a diagram showing the relationship between the ratio of the number of halogen atoms to the number of hydrogen atoms at the interface formed from an insulating film and a semiconductor substrate surface and the interface state density;

FIG. 4 is a diagram showing a relationship between a reverse applied voltage of a pn junction and a leakage current around the junction;

FIG. 5 is a diagram showing the relationship between the ratio of the number of fluorine atoms to the number of hydrogen atoms at the junction interface at the junction interface and the leakage current around the junction when the reverse direction applied voltage is 3 V;

FIG. 6 is a sectional view showing a schematic structure of a pn junction diode.

FIG. 7 is a diagram showing a relationship between a data retention time of a DRAM element and a hydrogen annealing temperature.

FIG. 8 is a sectional view showing a schematic structure of a DRAM element.

[Explanation of symbols]

1, 12, 23 ... Si substrate, 2, 13, 24 ... LOCOS oxide film, 3,
25… Gate oxide film, 4, 26, 29, 31… Polycrystalline Si film, 5,
17: LOCOS interface between oxide film and Si substrate, 6: Surface between gate oxide film and Si substrate, 9: Result of termination by chlorine and hydrogen, 10: Result of termination by bromine and hydrogen, 11: Result of termination by iodine and hydrogen , 14, 28 n-type diffusion layer, 15 aluminum electrode, 16 depletion layer, 18, 19, 20 leakage current around junction, 21 initial characteristics, 22 characteristics after applying electrical stress, 32 characteristics In case of electric furnace hydrogen annealing only, 33 ... hydrogen annealing by short-time heat treatment apparatus, 34 ... electric furnace hydrogen annealing with hydrogen annealing by short-time heat treatment apparatus, 51 ... LOCOS interface between oxide film and Si substrate 61, Characteristics at interface between gate oxide film and Si substrate.

──────────────────────────────────────────────────続 き Continuing on the front page (51) Int.Cl. ⁷ Identification symbol FI H01L 29/78 H01L 29/78 301F (72) Inventor Toshihiko Togahiko 1-280 Higashi-Koigabo, Kokubunji-shi, Tokyo Hitachi, Ltd. Central Research Laboratory (72) Inventor Toshiyuki Mine 1-280 Higashi-Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (56) References JP-A-4-62974 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) H01L 21/324 H01L 29/78

Claims (4)

(57) [Claims] A halogen is introduced into a semiconductor substrate on which an insulating film is formed by impurity implantation and thermal diffusion.
A method for manufacturing a semiconductor device, comprising: a first termination step of performing a heat treatment at 0 ° C .; and a second termination step of performing a heat treatment at a temperature of less than 400 ° C. in a hydrogen atmosphere . 2. The method of claim 1, method for manufacturing the semi-conductor device you wherein the halogen is fluorine. 3. A process for forming an isolation silicon oxide film and a gate oxide film on a silicon substrate by introducing a step of forming a gate electrode on the gate oxide film, the impurity implantation thermal diffusion halogen, 900
Heat-treating at 1000 ° C. to terminate the interface between the gate oxide film and the silicon substrate, and the interface between the device isolation silicon oxide film and the silicon substrate; forming a wiring layer and an interlayer insulating film; And heat treatment at less than 400 ° C. in a hydrogen atmosphere
And a step of further terminating the interface between the gate oxide film and the silicon substrate and the interface between the element isolation silicon oxide film and the silicon substrate. 4. The method according to claim 1, wherein
In a semiconductor device manufactured by a manufacturing method , hydrogen atoms 1 are attached to dangling bonds at the interface between an insulating film and a semiconductor substrate where atoms forming the insulating film and atoms forming the semiconductor substrate are not bonded. wherein a this <br/> and the halogen atoms formed by bonding the above hydrogen atom and a halogen atom at a ratio of 1 to 100 against.