JP4296807B2 - Manufacturing method of semiconductor device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor device having a semiconductor element formed by ion-implanting impurities into a semiconductor substrate and a polycrystalline silicon film formed on an insulating film provided on the same semiconductor substrate and into which impurities are ion-implanted. It relates to a manufacturing method.
[0002]
[Prior art]
A semiconductor element such as a transistor is formed by diffusing impurities in the semiconductor substrate. In addition, a polycrystalline silicon film is formed on the insulating film to form wiring and resistance. Some semiconductor devices include a diode formed using a polycrystalline silicon film on an insulating film. A manufacturing method of such a semiconductor device in which a polycrystalline silicon film is formed on an insulating film to form a diode is disclosed in, for example, Japanese Patent No. 2649359 (Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent No. 2649359
[0004]
[Problems to be solved by the invention]
Since a polycrystalline silicon film not containing impurities has almost no conductivity, a polycrystalline silicon film containing impurities is usually used to form wirings and resistors. When introducing an impurity into a polycrystalline silicon film, it may be introduced at the time of film formation, or may be introduced later by ion implantation. In particular, in the case of a polycrystalline silicon film used together with a semiconductor element such as a transistor as described above, in order to simplify the process, the ion implantation process at the element forming stage of a transistor or the like is used as it is to form a polycrystalline silicon film. Impurities are introduced.
[0005]
4A to 4C show a semiconductor element formed by implanting impurities into a semiconductor substrate and polycrystalline silicon formed on an insulating film provided on the same semiconductor substrate and implanted with impurities. It is a figure which shows the manufacturing method of the conventional semiconductor device 100 which has a film | membrane.
[0006]
FIG. 4A is a schematic cross-sectional view of the element portion and the polycrystalline silicon portion in the ion implantation process of the semiconductor device 100. FIG. 4B is a schematic plan view of an element portion and a polycrystalline silicon portion in the semiconductor device 100 corresponding to FIG. 4 (a) and 4 (b), the portion filled with dots is a region into which impurities after ion implantation are implanted, and the portion surrounded by a dotted line is a region in which the implanted impurities are diffused after heat treatment. ing. FIG. 4C is a diagram showing the impurity concentration distribution in the range indicated by the one-point difference line of the double-headed arrow in FIG. 4B with the same depth from the surface.
[0007]
4A and 4B, reference numeral 1 denotes a semiconductor substrate made of silicon, reference numeral 2 denotes an insulating film, and reference numeral 4 denotes a p + type well formed at the source of a transistor which is a semiconductor element. , P-conductivity type impurities are diffused at a high concentration. Reference numeral 5 denotes a thin oxide film for protecting the polycrystalline silicon film 3.
[0008]
In the semiconductor device 100 shown in FIGS. 4A and 4B, a p-conductivity type impurity is added to the polycrystalline silicon film 3 using the ion implantation process of the p-conductivity type impurity used for forming the p + type well of the element part as it is. Has been introduced. Thus, by using the ion implantation process to the semiconductor substrate 1 used for element formation as it is, the manufacturing process of the semiconductor device 100 can be simplified and the manufacturing cost of the semiconductor device 100 can be suppressed.
[0009]
However, the ion implantation process can be made common as described above because the impurity concentration Ks of the p + type well 4 and the impurity concentration K of the polycrystalline silicon film 3 are as shown in the distribution diagram of the impurity concentration in FIG. , Only if they are approximately equal. In particular, when the polycrystalline silicon film 3 is used for wiring or the like, the allowable range of the impurity concentration affecting the characteristics is large. However, as in Patent Document 1, when the polycrystalline silicon film 3 is used for a diode or a resistor. Has a narrow allowable range of impurity concentration affecting characteristics. Therefore, in such a case, the ion implantation process cannot be made common as described above, and the ion implantation into the polycrystalline silicon film 3 needs to be performed in a separate process. It was an obstacle to shortening and improving productivity.
[0010]
Accordingly, the present invention provides a semiconductor device that can be manufactured by using the same ion implantation process even if the required impurity concentration of the element portion is different from that of the polycrystalline silicon film, and the process can be shared. It aims to provide a method.
[0011]
[Means for Solving the Problems]
  According to a first aspect of the present invention, a semiconductor element formed by ion-implanting impurities into a semiconductor substrate and an insulating film provided on the semiconductor substrate are formed, and the impurities are ion-implanted.Used to form a diode in which p-conduction type diffusion regions and n-conduction type diffusion regions are alternately arranged.In the method of manufacturing a semiconductor device having a polycrystalline silicon film, a mask forming step of forming a mask having an opening made of a repetitive pattern on the polycrystalline silicon film, and simultaneously with ion implantation in the semiconductor element, An ion implantation step of ion-implanting impurities into the polycrystalline silicon film on which the mask is formed; and a heat treatment step of heat-treating the semiconductor substrate after the ion implantation.A second mask forming step of forming a second mask having an opening having a repetitive pattern on the polycrystalline silicon film after the heat treatment step; and the ions on the polycrystalline silicon film on which the second mask is formed. A second ion implantation step of implanting an impurity having a conductivity type opposite to that of the impurity ion-implanted in the implantation step, wherein a repetition period of the opening in the second mask is equal to that of the opening of the mask. Match the repetition periodIt is characterized by that.
According to a second aspect of the present invention, there is provided a semiconductor element formed by ion-implanting impurities into a semiconductor substrate, and an insulating film provided on the semiconductor substrate. In a manufacturing method of a semiconductor device having a polycrystalline silicon film used for forming a diode in which diffusion regions and n-conductivity type diffusion regions are alternately and repeatedly arranged, a mask having an opening made of a repetitive pattern is used as the polycrystal. A mask forming step formed on the silicon film; an ion implantation step of ion-implanting impurities into the polycrystalline silicon film on which the mask is formed simultaneously with ion implantation in the semiconductor element; and a semiconductor substrate after the ion implantation is completed. A heat treatment step for heat treatment, and a first step having openings having a repeated pattern on the polycrystalline silicon film after the heat treatment step. A second mask forming step for forming a mask; and a second ion for ion-implanting an impurity having a conductivity type opposite to the impurity ion-implanted in the ion implantation step into the polycrystalline silicon film on which the second mask is formed. And an implantation step, wherein the repeating pattern of the openings in the second mask is arranged so as to be substantially orthogonal to the repeating pattern of the openings in the mask.
[0012]
  In the manufacturing method of the semiconductor device according to claim 1 and claim 2,Impurities ion-implanted into the polycrystalline silicon film are diffused uniformly throughout the polycrystalline silicon film in the next heat treatment step because the implanted region has a repeated pattern. In addition, the aperture ratio of the opening can be set as appropriate to control the amount of impurities ion-implanted into the polycrystalline silicon film, and the impurity concentration of the polycrystalline silicon film after the heat treatment can be adjusted to an arbitrary required value. In this way, the ion implantation of the semiconductor element and the polycrystalline silicon film, which require different impurity concentrations, can be performed in one process using the ion implantation conditions of the semiconductor element. Therefore, by sharing the ion implantation process in this way, it is possible to reduce the cost, shorten the TAT, and improve the productivity of the semiconductor device having the semiconductor elements having different impurity concentrations and the polycrystalline silicon film. .
[0013]
  Conversely, if it is assumed that the ion implantation process into the polycrystalline silicon film is made common with the ion implantation process in the semiconductor element formation, the impurity concentration of the polycrystalline silicon film is set as compared with the conventional case. The range can be expanded and the degree of freedom of design is expanded.
In the method for manufacturing a semiconductor device according to claim 1 or 2, the polycrystalline silicon film is used for forming a diode in which p-conduction type diffusion regions and n-conduction type diffusion regions are alternately arranged. A second mask forming step of forming a second mask having an opening having a repetitive pattern on the polycrystalline silicon film after the heat treatment step; and the polycrystalline silicon film on which the second mask is formed, A second ion implantation step of ion-implanting an impurity having a conductivity type opposite to that of the impurity ion-implanted in the ion implantation step.
According to this, even in a diode in which the impurity concentration has a great influence on the characteristics, the ion implantation process of either the p conductivity type or the n conductivity type is made common with the ion implantation process in the semiconductor element formation. be able to. Therefore, cost reduction, TAT shortening, and productivity improvement can be achieved for a semiconductor device having a semiconductor element and a diode made of a polycrystalline silicon film.
In particular, the method for manufacturing a semiconductor device according to claim 1 is characterized in that the repetition period of the opening in the second mask coincides with the repetition period of the opening of the mask.
According to this, even if the impurity is not sufficiently diffused and a periodic distribution occurs in the impurity concentration after the heat treatment, all diffusions of the p conductivity type or the n conductivity type formed by the second mask having the same period are used. The effect is even on the area. Therefore, a semiconductor device in which a diode having good characteristics is formed without losing the current balance of the diode can be manufactured.
The method for manufacturing a semiconductor device according to claim 2 is characterized in that the repeated pattern of the opening in the second mask is arranged substantially orthogonal to the repeated pattern of the opening in the mask. It is said.
According to this, even if the impurity is not sufficiently diffused and a periodic distribution occurs in the impurity concentration after the heat treatment, the p-conductivity type or the n-conductivity type formed by the second mask against this periodic distribution. The regions are formed so as to be substantially orthogonal. For this reason, the influence on the diode characteristics due to the pattern misalignment between the mask and the second mask is small, and the design margin of the diode can be increased.
[0014]
  Claim3~6The present invention relates to an opening formed of a repetitive pattern of a mask in the method for manufacturing a semiconductor device.
[0015]
  Claim3~5The invention described in 1 is an opening having a repetitive pattern suitable for a planar shape of a polycrystalline silicon film having a stripe shape. Claim3When4According to the invention described in (2), the planar shape of the opening of the mask is a stripe shape parallel to the vertical direction with respect to the long side direction of the stripe of the polycrystalline silicon film. Claims5The invention described in (2) is characterized in that it crosses diagonally in the long side direction of the stripe.
[0016]
Even with a mask having an opening made of any of the above repetitive patterns, impurities can be uniformly diffused throughout the polycrystalline silicon film by heat treatment after ion implantation, and the impurity concentration of the polycrystalline silicon film can be arbitrarily set. Can be adjusted to the required value.
[0017]
Further, for example, when a mask having a stripe-shaped opening perpendicular to the long side direction of the stripe of the polycrystalline silicon film is used, there are the following advantages. In this case, even if the impurity diffusion is insufficient and the uniformity of the impurity concentration after the heat treatment is slightly deteriorated, the influence on the current flowing in the long side direction of the stripe is small. On the other hand, when the uniformity of the impurity concentration after the heat treatment is greatly deteriorated, the current hardly flows in the long side direction of the stripe, and the influence on the current flowing in the short side direction of the stripe is small.
[0018]
Conversely, when using a mask having a stripe-shaped opening parallel to the long-side direction of the stripe of the polycrystalline silicon film, even if the uniformity of the impurity concentration after heat treatment is slightly degraded, The influence on the current flowing in the short side direction of the stripe is reduced. Further, when the uniformity of the impurity concentration after the heat treatment is greatly deteriorated, the current hardly flows in the short side direction of the stripe, and the influence on the current flowing in the long side direction becomes small.
[0019]
When a mask having an opening that obliquely intersects the long side direction of the stripe of the polycrystalline silicon film is used, the influence of current flowing in the long side direction and the short side direction of the stripe is evenly reduced. As described above, by selecting each of the masks according to the use of the polycrystalline silicon film, even when the uniformity of the impurity concentration after the heat treatment is deteriorated, the influence can be reduced.
[0020]
  Claim6In the invention described in item 1, the openings of the mask are arranged in a lattice pattern on the polycrystalline silicon film.
[0021]
Also by this, the heat treatment after the ion implantation can diffuse the impurities uniformly throughout the polycrystalline silicon film, and the impurity concentration of the polycrystalline silicon film can be adjusted to an arbitrary required value. In the case of the present invention, since the openings are isotropically arranged, the opening ratio of the openings can be set small while maintaining isotropicity, and the impurity concentration of the polycrystalline silicon film is desired to be set low and uniform. It is particularly effective.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0031]
  FIG. 1A is a schematic cross-sectional view of an element portion of a semiconductor element and a polycrystalline silicon portion on which a polycrystalline silicon film is formed in an ion implantation process of the semiconductor device 101. FIG. 1B is a schematic plan view of an element portion and a polycrystalline silicon portion in the semiconductor device 101 corresponding to FIG. In FIGS. 1 (a) and 1 (b), a portion filled with dots is a region into which impurities after ion implantation are implanted, and a portion surrounded by a dotted line is a region in which the implanted impurities are diffused after heat treatment. ing. FIG. 1C is a diagram showing the impurity concentration distribution in the range indicated by the one-dot difference line of the double-ended arrow in FIG. 1B with the same depth from the surface. 1A to 1C, parts that are the same as those of the conventional semiconductor device 100 shown in FIGS. 4A to 4C are assigned the same reference numerals, and descriptions thereof are omitted. Also,FigureThe element portion of the semiconductor device 101 in 1 (a) to (c) is exactly the same as the element portion of the semiconductor device 100 in the conventional FIG. 4 (a) to (c).
[0032]
Also in the method of manufacturing the semiconductor device 101 shown in FIGS. 1A to 1C, the ion implantation conditions used for forming the p + type well 4 of the element portion are used as they are in the conventional manner to the polycrystalline silicon film 30. Impurities are introduced.
[0033]
  On the other hand, as shown in FIG.HalfAt the time of ion implantation of the conductor device 101, unlike the conventional manufacturing method of FIG. 4A, the mask 9 having the opening 90 r having a repeated pattern is formed on the polycrystalline silicon film 30. Therefore, after ion implantation, an impurity implantation region 30r having a repetitive pattern corresponding to the opening 90r having a repetitive pattern is formed in the polycrystalline silicon film 30. In FIG. 1B, the mask 9 is not shown for simplicity.
[0034]
As described above, the impurity implantation region 30r having a repetitive pattern is formed in the polycrystalline silicon film 30 after the ion implantation, but the implanted impurities are uniformly distributed throughout the polycrystalline silicon film 30 by the next heat treatment process. Spread. For this reason, as shown in the distribution diagram of the impurity concentration in FIG. 1C, the impurity concentration C of the polycrystalline silicon film 30 is set to the impurity concentration K of the polycrystalline silicon film 3 in FIGS. On the other hand, C = K × (β / α). Accordingly, the aperture ratio (β / α in FIG. 1B) of the opening 90r of the mask 9 is appropriately set, and the amount of impurities ion-implanted into the polycrystalline silicon film 30 is controlled, so that after the heat treatment. The impurity concentration C of the polycrystalline silicon film 30 can be adjusted to an arbitrary required value.
[0035]
In this way, ion implantation of the p + type well 4 and the polycrystalline silicon film 30 of the semiconductor element requiring different impurity concentrations Ks and C is performed using the ion implantation conditions of the p + type well 4 of the semiconductor element. This can be done in two steps. Therefore, by making the ion implantation process common in this way, in manufacturing the semiconductor device 101 having the p + type well 4 and the polycrystalline silicon film 30 of semiconductor elements having different impurity concentrations, cost reduction and TAT reduction are achieved. , Productivity can be improved.
[0036]
In other words, if it is assumed that the ion implantation process into the polycrystalline silicon film 30 is made common with the ion implantation process in the semiconductor element formation, the impurity concentration of the polycrystalline silicon film 30 compared to the conventional case. Setting range can be expanded, and the degree of freedom of design is expanded.
[0037]
FIGS. 2A to 2D show four types of openings made up of repeated patterns included in the mask used in the above-described method for manufacturing a semiconductor device. 2A to 2D are schematic plan views of the polycrystalline silicon films 31 to 34 corresponding to FIG. 1B, and impurity implantation regions 31r to 34r formed in the polycrystalline silicon films 31 to 34, respectively. Corresponds to the opening of the mask.
[0038]
The planar shape of the polycrystalline silicon films 31 to 34 shown in FIGS. 2A to 2D is a stripe shape. 2A and 2A, the planar shape of the impurity implantation region 31r corresponding to the opening of the mask is a stripe shape perpendicular to the long side direction of the stripe of the polycrystalline silicon film 31. FIG. Yes. On the other hand, in FIGS. 2B and 2B, the planar shape of the impurity implantation region 32 r is a stripe shape parallel to the long side direction of the stripe of the polycrystalline silicon film 32. In FIG. 2C, the planar shape of the impurity implantation region 33r is a stripe shape that crosses obliquely in the long side direction of the stripe of the polycrystalline silicon film 33.
[0039]
Even if it is a mask having an opening made of any of the repeated patterns of FIGS. 2A to 2C, the entire polycrystalline silicon films 31 to 33 as shown by the dotted line by the heat treatment after ion implantation, Impurities can be diffused uniformly. Therefore, it is possible to set the aperture ratio as appropriate and adjust the impurity concentration of the polycrystalline silicon films 31 to 33 to an arbitrary required value.
[0040]
Further, as shown in FIGS. 2A and 2A, an impurity implantation region 31r is formed using a mask having a stripe-shaped opening perpendicular to the long side direction of the stripe of the polycrystalline silicon film 31. When formed, there are the following advantages. As shown in FIG. 2A, even if the impurity diffusion is not sufficient and the uniformity of the impurity concentration after the heat treatment is slightly deteriorated, the current indicated by the arrow in the figure flowing in the long side direction of the stripe The impact is small. On the other hand, as shown in FIG. 2 (a ′), when the uniformity of the impurity concentration after the heat treatment is greatly deteriorated, the current hardly flows in the long side direction of the stripe, and the current flowing in the short side direction of the stripe On the other hand, the impact is small.
[0041]
On the other hand, as shown in FIGS. 2B and 2B ′, when a mask having a stripe-shaped opening parallel to the long side direction of the stripe of the polycrystalline silicon film 32 is used, There are advantages. As shown in FIG. 2B, even if the impurity diffusion is not sufficient and the uniformity of the impurity concentration after the heat treatment is slightly deteriorated, the current indicated by the arrow in the figure flowing in the short side direction of the stripe The impact is small. On the other hand, as shown in FIG. 2 (b ′), when the uniformity of the impurity concentration after the heat treatment is greatly deteriorated, the current hardly flows in the short side direction of the stripe, and the current flowing in the long side direction of the stripe On the other hand, the impact is small.
[0042]
As shown in FIG. 2C, when a mask having an opening that obliquely intersects the long side direction of the stripe of the polycrystalline silicon film 33 is used, the current flowing in the long side direction and the short side direction of the stripe On the other hand, the influence is equally reduced.
[0043]
As described above, the uniformity of the impurity concentration after the heat treatment is deteriorated by selecting each mask corresponding to the above-described FIGS. 2A to 2C according to the use of the polycrystalline silicon films 31 to 33. However, the influence can be reduced.
[0044]
In FIG. 2D, impurity implantation regions 34r corresponding to the openings of the mask are arranged on the polycrystalline silicon film 34 in a lattice pattern. Also by this, the heat treatment after the ion implantation can diffuse the impurities uniformly throughout the polycrystalline silicon film 34, and the impurity concentration of the polycrystalline silicon film 34 can be adjusted to an arbitrary required value. In the case of FIG. 2D, since the impurity implantation region 34r corresponding to the opening is isotropically arranged, the opening ratio of the opening can be set small while maintaining the isotropic property. This is particularly effective when it is desired to set the impurity concentration of 34 low and uniformly.
[0045]
Next, a case will be described below in which a diode in which p conductivity type diffusion regions and n conductivity type diffusion regions are alternately arranged is formed using the polycrystalline silicon film.
[0046]
FIGS. 3A to 3F are cross-sectional views showing a method for manufacturing a diode formed on the polycrystalline silicon film on the insulating film. This diode is a part of the semiconductor device formed together with the semiconductor element as described above. In FIGS. 3A to 3F, only the polycrystalline silicon portion is shown. 3A to 3F, parts that are the same as those of the semiconductor device 101 shown in FIGS. 1A to 1C are given the same reference numerals, and descriptions thereof are omitted.
[0047]
First, as shown in FIG. 3A, an insulating film 2 is formed on a semiconductor substrate 1, a polycrystalline silicon film 35 to which no impurity is added is formed thereon, and patterned into a predetermined shape. . Next, the patterned polycrystalline silicon film 35 is thermally oxidized to form a thin oxide film 5 for protection.
[0048]
Next, as shown in FIG. 3B, a mask 9a having an opening 90ar having a repetitive pattern is formed on the polycrystalline silicon film 35, and a p-conductivity type impurity is ion-implanted. This ion implantation is performed using the ion implantation conditions of the semiconductor element formed in the element portion as described above, and the ion implantation process is made common. By ion implantation, an impurity implantation region 35r corresponding to the opening 90ar having a repetitive pattern is formed as shown in the figure.
[0049]
Next, as shown in FIG. 3C, a heat treatment is performed after the mask 9a is removed, and the implanted p-conductivity type impurities are diffused throughout the polycrystalline silicon film 35. Next, as shown in FIG. As a result, the polycrystalline silicon film 35 becomes a polycrystalline silicon film in which p conductivity type impurities are uniformly diffused.
[0050]
Next, as shown in FIG. 3D, a second mask 9b having an opening 90bs having a repetitive pattern is formed on the polycrystalline silicon film 35, and n-conductivity type impurities are ion-implanted. By this second ion implantation, an impurity implantation region 35s corresponding to the opening 90bs having a repetitive pattern is formed as shown in the figure.
[0051]
Finally, as shown in FIG. 3E, after the second mask 9b is removed, the interlayer insulating film 6 is formed, the electrodes 7 are connected, and the p-conduction type diffusion region 35p and the n-conduction type diffusion region 35n are formed. A diode 102d that is alternately and repeatedly arranged is completed.
[0052]
Thus, even a diode whose impurity concentration has a great influence on characteristics can be shared with an ion implantation step in semiconductor element formation, as shown in FIG. In FIG. 3B, the ion implantation process of the p-conductivity type impurity is made common with the ion implantation process in the formation of the semiconductor element. A polycrystalline silicon film in which the impurities are uniformly diffused may be formed. In this manner, the semiconductor device having the diode 102d made of the semiconductor element and the polycrystalline silicon film 35 can be reduced in cost, TAT, and productivity.
[0053]
Note that the repetition period La of the opening 90ar of the mask 9a indicated by the one-dotted line of the double-ended arrow in FIG. 3B matches the repetition period Lb of the opening 90bs in the second mask 9b of FIG. 3D. It is preferable to do. Thereby, even if the impurity is not sufficiently diffused and a periodic distribution occurs in the impurity concentration after the heat treatment shown in FIG. 3C, all the n-conductivity formed by the second mask 9b having the same period. The influence is uniform on the mold diffusion region 35n. Therefore, the current balance of the diode 102d is not lost, and a semiconductor device in which a diode with favorable characteristics is formed can be obtained.
[0054]
In the diode 102d shown in FIGS. 3A to 3E, the repeating pattern of the opening 90bs in FIG. 3D is arranged in parallel to the repeating pattern of the opening 90ar in FIG. It was a formed diode. However, the present invention is not limited thereto, and the repeating pattern of the opening 90bs in FIG. 3D may be arranged so as to be substantially orthogonal to the repeating pattern of the opening 90ar in FIG.
[0055]
According to this, even if the impurity diffusion shown in FIG. 3C is not sufficient and a periodic distribution occurs in the impurity concentration after the heat treatment, this periodic distribution is formed by the second mask 9b. The p-conductivity type or n-conductivity type regions are formed so as to be substantially orthogonal. For this reason, the influence on the diode characteristics due to the pattern misalignment between the mask 9a and the second mask 9b is small, and the design margin of the diode can be increased.
[Brief description of the drawings]
1A is a schematic cross-sectional view of an ion implantation step in a method for manufacturing a semiconductor device according to the present invention, FIG. 1B is a schematic plan view, and FIG. 1C is a diagram showing a distribution of impurity concentration; .
FIGS. 2A to 2D are schematic plan views of a polycrystalline silicon film in which each impurity implantation region is formed corresponding to an opening made of a repetitive pattern of a mask used in the present invention.
FIGS. 3A to 3E are cross-sectional views by process showing a method for manufacturing a diode formed on a polycrystalline silicon film of the present invention. FIGS.
4A is a schematic cross-sectional view of an ion implantation step in a conventional method for manufacturing a semiconductor device, FIG. 4B is a schematic plan view, and FIG. 4C is a diagram showing a distribution of impurity concentration;
[Explanation of symbols]
1 Semiconductor substrate
2 Insulating film
3,30-35 polycrystalline silicon film
30r to 35r, 35s impurity implantation region
35pp diffusion type diffusion region
35n n conductivity type diffusion region
4 p + type well
5 Thin oxide film
6 Interlayer insulation film
7 electrodes
9,9a mask
9b Second mask
90r, 90ar, 90bs Opening consisting of repeated patterns
100, 101 Semiconductor device
102d diode

Claims (6)

A semiconductor element formed by ion-implanting impurities into a semiconductor substrate and an insulating film provided on the semiconductor substrate are formed. Impurities are ion-implanted to alternately form p-conduction type diffusion regions and n-conduction type diffusion regions. the method of manufacturing a semiconductor device having a polycrystalline silicon film that is used in the form of repeated arranged comprising a diode,
A mask forming step of forming a mask having an opening made of a repetitive pattern on the polycrystalline silicon film;
An ion implantation step of implanting impurities into the polycrystalline silicon film on which the mask is formed simultaneously with ion implantation in the semiconductor element;
A heat treatment step of heat treating the semiconductor substrate after the ion implantation ;
A second mask forming step of forming a second mask having openings having a repeated pattern on the polycrystalline silicon film after the heat treatment step;
A second ion implantation step of ion-implanting an impurity having a conductivity type opposite to the impurity ion-implanted in the ion implantation step into the polycrystalline silicon film on which the second mask is formed;
A method of manufacturing a semiconductor device , wherein a repetition period of the opening in the second mask matches a repetition period of the opening in the mask . A semiconductor element formed by ion-implanting impurities into a semiconductor substrate and an insulating film provided on the semiconductor substrate are formed. Impurities are ion-implanted to alternately form p-conduction type diffusion regions and n-conduction type diffusion regions. In a method of manufacturing a semiconductor device having a polycrystalline silicon film used for forming a diode that is repeatedly arranged,
A mask forming step of forming a mask having an opening made of a repetitive pattern on the polycrystalline silicon film;
An ion implantation step of implanting impurities into the polycrystalline silicon film on which the mask is formed simultaneously with ion implantation in the semiconductor element;
A heat treatment step of heat treating the semiconductor substrate after the ion implantation;
A second mask forming step of forming a second mask having openings having a repeated pattern on the polycrystalline silicon film after the heat treatment step;
A second ion implantation step of ion-implanting an impurity having a conductivity type opposite to the impurity ion-implanted in the ion implantation step into the polycrystalline silicon film on which the second mask is formed;
Method for producing a relative repetitive pattern of openings in the mask, repeating pattern of openings in said second mask, semiconductors devices you being disposed so as to be substantially orthogonal. The planar shape of the polycrystalline silicon film is a stripe shape,
3. The method of manufacturing a semiconductor device according to claim 1, wherein a planar shape of the opening of the mask is a stripe shape perpendicular to a long side direction of the stripe of the polycrystalline silicon film. The planar shape of the polycrystalline silicon film is a stripe shape,
3. The method of manufacturing a semiconductor device according to claim 1, wherein a planar shape of the opening of the mask is a stripe shape parallel to a long side direction of the stripe of the polycrystalline silicon film. The planar shape of the polycrystalline silicon film is a stripe shape,
3. The method of manufacturing a semiconductor device according to claim 1, wherein the planar shape of the opening of the mask is a stripe shape that crosses obliquely in the long side direction of the stripe of the polycrystalline silicon film . 3. The method of manufacturing a semiconductor device according to claim 1 , wherein the openings of the mask are arranged in a lattice pattern on the polycrystalline silicon film .

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