JP6028515B2 - Ion beam irradiation equipment - Google Patents

Description

  The present invention relates to a mask used when an ion beam is irradiated onto a substrate having a dimension larger than the long side of the beam cross section using an ion beam having a rectangular beam cross section, and an ion using the mask. The present invention relates to a beam irradiation apparatus.

  For example, a substrate used for a flat panel display or the like is increasing in size in order to improve productivity. On the other hand, since it is difficult to increase the size of the ion beam used for ion implantation in accordance with the increase in size of the substrate, in recent years, the size of each side of the substrate is larger than the size in the long side direction of the ribbon-like ion beam. Is bigger. For this reason, when irradiating a ribbon-like ion beam on the entire surface of a large substrate, a method of irradiating the entire surface of the substrate with two ion beams as disclosed in Patent Document 1, or Patent Document A method of irradiating the entire surface of the ion beam by reciprocating the substrate a plurality of times with respect to one ion beam as shown in FIG.

  The conventional ion beam irradiation method will be described more specifically with reference to FIG. 13 or FIG. 13 and 14, the incident direction of the ion beam IB with respect to the substrate W is set as the Z axis, the short side direction in the beam cross section of the ion beam IB is set as the X axis, and the long side direction in the beam cross section is set as the Y axis. The coordinate axes are set so that a horizontal plane is formed by the X axis and the Y axis.

  As shown in FIG. 13A, an ion beam irradiation apparatus 100A described in Patent Document 1 includes two ribbon-like ion beams IB (a) and IB in ion implantation chambers 1A (a) and 1A (b). (B) is introduced, and the irradiation position is shifted up and down, respectively, so that the upper end position of one ion beam IB (a) and the lower end position of the other ion beam IB (b) are substantially the same height. It is. Then, the substrate W raised as shown in FIG. 13B is allowed to pass across the respective ion beams IB (a) and IB (b), whereby one ion beam IB (a) is passed through the substrate W. And the other ion beam IB (b) is irradiated to the upper half of the substrate W so as to cross the substrate W once with respect to the ion beams IB (a) and IB (b). As a result, the entire surface of the substrate W is irradiated with the ion beams IB (a) and IB (b).

  By the way, although the ribbon-like ion beams IB (a) and IB (b) have a substantially constant irradiation amount in the central portion, repulsion due to electric charges is generated between the ions, so that the end portions are compared with the central portion. The amount of irradiation gradually changes and becomes smaller. Therefore, if the upper and lower ends of the two ion beams IB (a) and IB (b) are simply set at the same position, the irradiation amount of the ion beam IB at the central portion of the substrate W is desirable as compared with other portions of the substrate W. Will greatly deviate from the amount of irradiation. Therefore, in the ion beam irradiation apparatus 100A of Patent Document 1, the masks 5A (a) and 5A (b) for shaping the ends of the ion beam IB are placed on the passage paths of the ion beams IB (a) and IB (b). Is provided. As shown in FIG. 13C, the masks 5A (a) and 5A (b) have a shape in which the tip portion is inclined obliquely in the short side direction in the beam cross section, and the long side direction in the beam cross section. By appropriately setting the position, an irradiation amount comparable to that of other portions can be obtained in the central portion of the substrate W.

  However, in this Patent Document 1, although it is possible to roughly adjust the uniformity of the dose to the substrate by adjusting the position of each mask provided for each ion beam, eventually, Since it is greatly affected by the inclination angle of the oblique portion at the front end of the mask, it is difficult to further improve the uniformity of the dose compared with the current situation.

  This is because, in the mask shape of Patent Document 1, the design parameter that can be changed is substantially only the inclination angle of the tip portion. Therefore, the adjustment parameter is used to appropriately match the mask shape in accordance with the dose distribution of the ion beam. This is because, for example, when the uniformity of the irradiation amount in a certain region is a problem, it is very difficult to appropriately correct only that portion without adversely affecting other portions.

  Further, the technical problem related to the mask for shaping the end of the ion beam similarly occurs in the ion beam irradiation method of Patent Document 2.

  In the ion beam irradiation apparatus 100B described in Patent Document 2, a plurality of cell regions W1 that are actually used as products and a divided band W2 formed between the cell regions W1 are formed on the glass substrate W. It is used for multi-surface ion implantation. That is, as shown in FIG. 14, the dividing bands W2 on the glass substrate W are formed in a lattice shape, and each cell region W1 is disposed between the lattices.

  In this ion beam irradiation apparatus 100B, a rectangular mask 5B is disposed at both ends of the ion beam IB as shown in FIGS. 14A and 14B, so that the ion beam IB as shown in FIG. 14C. The glass substrate W is irradiated only with a beam having a good uniformity at the central portion AR. Further, in this ion beam irradiation apparatus 100B, when the glass substrate W is reciprocated while changing the position in the vertical direction with respect to the ion beam IB as shown in FIG. 14 (d), the end of the ion beam IB is divided. It is configured to pass through the belt W2.

  In recent years, it has been required to reduce the size of the dividing band so that a plurality of cell regions as large as possible can be formed from a single glass substrate. It is difficult to strictly control the irradiation dose in the area and the size of the non-uniform irradiation dose, and it is impossible to maintain the uniformity of the irradiation dose in the cell area if you try to answer such a demand. End up.

  In other words, in any ion beam irradiation method, since there is no mask having a shape suitable for adjusting the dose at the end of the ion beam at present, it is possible to improve the uniformity of the ion beam dose on a large substrate. However, it is not possible to meet the demands for downsizing of the divided bands in multi-surface processing.

JP 2011-192583 A JP 2009-134923 A

  The present invention has been made in view of the above-described problems, and the irradiation dose uniformity at the end of the ion beam and the size of the region where the uniformity is maintained are simple. It is an object of the present invention to provide a mask that can be easily adjusted and an ion beam irradiation apparatus using the mask.

  That is, the mask of the present invention is a mask provided so as to shield an end portion in the long side direction in the beam cross section with respect to an ion beam having a substantially rectangular beam cross section in a cross section orthogonal to the beam traveling direction, When the mask is viewed from the beam traveling direction of the ion beam, the mask extends in the long side direction from one short side of the beam cross section, and shields a part of the end of the ion beam. And extending in the long side direction from one short side of the beam cross section and arranged side by side in the short side direction in the beam cross section with respect to the first shielding part, and at the end of the ion beam, the first part A second shielding part that shields a part other than the part shielded by the shielding part, and the amount of ion beam shielding by the first shielding part and the ion shielding by the second shielding part. Characterized in that it made different shielding of the beam, respectively.

  In such a case, since the mask includes the first shielding part and the second shielding part provided side by side in the short side direction in the beam cross section, the short side direction in the beam cross section of the ion beam is set. By combining the first profile of the dose determined by the first shielding part and the second profile of the dose determined by the second shielding part with respect to the substrate passing therethrough, it is possible to cancel the excess / deficiency of the dose by conventional methods. Can be irradiated with uniformity.

  That is, the shielding amount determined by the shape and size of the first shielding part and the shielding amount determined by the shape and dimension of the second shielding part can be set independently, and the first profile and the second profile can be set in various modes. In addition, since they can be freely combined, it is easy to obtain a desired dose distribution at the end of the ion beam.

  More specifically, given the uniformity of the dose desired to be achieved at the end of the ion beam and the size of the uniform range, there is one adjustment parameter for a mask formed in a single shape. Even with the dose distribution that was difficult to realize, the amount of shielding was changed by changing a plurality of adjustment parameters such as the shape of the first shielding part and the second shielding part, the dimension in the long side direction in the beam cross section, and the ratio in the short side direction. This can be realized by making them different.

  For these reasons, for example, the accuracy of adjustment of the dose in the region where the ends are overlapped using two ion beams is further improved, or the region where the uniformity of the ion beam is not maintained is made as small as possible. It is possible to make the dividing band in multi-chamfer smaller.

  In order to easily realize the target irradiation amount at the end portion of the ion beam by the combination of the first irradiation amount formed by the first shielding portion and the second irradiation amount formed by the second shielding portion, The ratio of the first width dimension which is the width dimension in the short side direction in the beam cross section of one shielding part and the second width dimension which is the width dimension in the short side direction in the beam section of the second shielding part is What is necessary is just to be determined based on the target dose of the ion beam at the end.

  While simplifying the shape of the mask, it is easy for the total irradiation amount when the first irradiation amount formed by the first shielding portion and the second irradiation amount formed by the second shielding portion are combined. In order to make it easier to obtain the target irradiation amount at the end of the ion beam, the first shielding part and the second shielding part have a substantially rectangular shape when viewed from the beam traveling direction of the ion beam. Anything can be used.

  Without producing a mask with a special shape, the amount of shielding in the first shielding portion and the second shielding portion can be made different by simply combining a mask with a simple shape such as a general-purpose square. In order to make it easy to obtain the target irradiation amount by the combination, it is only necessary that the first shielding part and the second shielding part are provided separately.

  For example, even when the irradiation position of the ion beam is displaced in the long side direction in the beam cross section for some reason or the irradiation amount distribution at the end when the ion beam is emitted from the ion source is changed, the first shielding unit is appropriately used. In order to adjust the shielding amount of the second shielding part and obtain the target irradiation amount, the first length dimension which is the length dimension in the long side direction in the beam cross section of the first shielding part; It is only necessary that the second length dimension, which is the length dimension in the long side direction in the beam cross section of the second shielding portion, can be independently changed.

  Even if the ion beam irradiation position is shifted in the direction of the short side of the beam cross section, in order to obtain the target irradiation amount as designed without changing the masking amount by the mask, the ion beam beam travels. When viewed from the direction, the mask extends in the long side direction from one short side of the beam cross section and is aligned in the short side direction in the beam cross section so as to sandwich the second shielding part with the first shielding part. And a first length dimension that is a length dimension in a long side direction in the beam cross section of the first shielding section, and a long side direction in the beam cross section of the third shielding section. The 3rd length dimension which is a length dimension should just be set to the same value, respectively. In such a case, even if the irradiation position of the ion beam is shifted in the short side direction in the beam cross section, the sum of the amount of the ion beam shielded by the first shielding portion and the third shielding portion is always the same. The shielding amount by the second shielding part between the first shielding part and the third shielding part does not change in the first place with respect to the deviation in the short side direction in the beam cross section. From these things, since the same shielding amount can be maintained in each part, it becomes possible not to be influenced by the shift in the short side direction in the beam cross section of the ion beam.

  With an ion beam irradiation apparatus using a mask as described above, the irradiation amount at the end of the ion beam can be easily adjusted. Further, it is possible to further improve the uniformity of the irradiation amount of the overlapping portion, or to make the region as small as possible even if there is a non-uniform portion. Therefore, in applications such as irradiating an ion beam to a large substrate, the quality of the product can be further improved by improving the uniformity of the ion beam irradiation amount, and the size of the dividing band can be further increased if multiple surfaces are used. The cell area can be increased by reducing the cell area, and the productivity can be further improved.

  As described above, the mask of the present invention and the ion beam irradiation apparatus using the mask have the first shielding part and the second shielding part, and the dimension in the long side direction and the short side direction in these beam cross sections. Since a plurality of adjustment parameters such as the above-mentioned dimensions can be independently adjusted, it is possible to easily adjust the dose at the end of the ion beam. Therefore, it is possible to realize even the irradiation dose uniformity which is difficult to achieve because there is only a single adjustment parameter as in the conventional oblique mask and rectangular mask.

The schematic diagram which shows the whole ion beam irradiation apparatus which concerns on one Embodiment of this invention. The schematic diagram which shows the arrangement | positioning and shape of a mask in the embodiment. The schematic diagram in case the rectangular mask which is the previous step for designing the mask in the embodiment is arranged at a position away from the center of the ion beam by DLT1. The graph which shows a beam profile when a rectangular mask is provided in the position away from the ion beam center by DLT1. The schematic diagram in case the rectangular mask which is the front | former stage for designing the mask in the embodiment is arrange | positioned in the position away from the ion beam center by DLT2. 6 is a graph showing a beam profile when a rectangular mask is provided at a position away from the ion beam center by DLT2. The schematic diagram which shows the relationship between arrangement | positioning of a rectangular mask, and the beam profile formed in an ion beam overlap part. The schematic diagram shown about the length dimension and width dimension which are the values designed of the mask in the embodiment. The graph shown about the beam profile of the mask designed like FIG. The schematic diagram which shows the mask comprised from the several mask member which concerns on another embodiment of this invention. The schematic diagram which shows the shape of the mask which concerns on another embodiment of this invention. The schematic diagram which shows the shape of the mask which concerns on different embodiment of this invention. The schematic diagram which shows the conventional mask and ion beam irradiation apparatus. The schematic diagram which shows another conventional mask and ion beam irradiation apparatus.

  An embodiment of the mask 5 of the present invention and an ion beam irradiation apparatus 100 using the mask 5 will be described with reference to FIGS. In each drawing to be referred to, the same coordinate axes as those set in FIGS. 13 and 14 are set, the incident direction of the ion beam IB with respect to the substrate W is the Z axis, and the short side in the beam cross section of the ion beam IB is set. The direction is set as the X axis, the long side direction in the beam cross section is set as the Y axis, and the coordinate axes are set so that the horizontal plane is formed by the X axis and the Y axis.

  The ion beam irradiation apparatus 100 according to the present embodiment transports a large substrate W upright as shown in FIG. 1A in the X-axis direction from the left side to the right side in the drawing, and uses two ion beams. The entire surface of the substrate W is irradiated by irradiating the ion beam IB to the lower half and the upper half of the substrate W, respectively.

  That is, in the ion beam irradiation apparatus 100, the substrate W under atmospheric pressure is sequentially loaded from the left side in the drawing, and the load beam chamber 3, the first waiting chamber 2, and the lower half of the substrate W are depressurized. A first processing chamber 1 (a) in which IB is irradiated, a second waiting chamber 2, a second processing chamber 1 (b) in which the upper half of the substrate W is irradiated with an ion beam IB, a third waiting chamber 2, An unload lock chamber 4 from which the substrate W is unloaded after being released from the vacuum pressure to the atmospheric pressure. Each chamber is connected by a vacuum valve, and each waiting chamber 2 is for holding the substrate W until the treatment in the next chamber is completed. Moreover, each room other than the load lock chamber 3 and the unload lock chamber 4 is kept in a high vacuum.

  The first processing chamber 1 (a) and the second processing chamber 1 (b) are respectively provided with ribbon-like ion beams IB (a) supplied from separate ion beam supply devices 11 (a) and 11 (b), respectively. IB (b) is introduced into the room, and the irradiation positions of the ion beams IB (a) and IB (b) are different in the vertical direction as shown in the front view of FIG. 1B. . More specifically, in the first ion beam IB (a) introduced into the first processing chamber 1 (a), the long side direction coincides with the vertical direction at a position corresponding to the lower half of the substrate W to be transferred. The second ion beam IB (b) introduced into the second processing chamber 1 (b) has a long side direction in a vertical direction at a position corresponding to the upper half of the substrate W to be transported. Irradiated to match.

  The first processing chamber 1 (a) is provided with a first mask 5 (a) for shaping the upper end of the first ion beam IB (a), and the second processing chamber 1 (b) A second mask 5 (b) for shaping the lower end of the second ion beam IB (b) is provided. In the present embodiment, the first mask 5 (a) and the second mask 5 (b) have the same shape and are arranged so as to be symmetric. Further, each processing chamber 1 (a), 1 (b) is provided with a measurement unit for obtaining the irradiation dose distribution of the ion beam IB after passing through each mask 5 (a), 5 (b). is there.

  Next, a specific shape of the mask 5 will be described. Since the first mask 5 (a) and the second mask 5 (b) have the same shape, they will be described below as being common. In addition, if there is no need to distinguish between them, only numeric numbers are assigned.

  As shown in FIG. 2, the mask 5 is for shaping the end portion of the ribbon-like ion beam IB. When viewed along the short side direction (X-axis direction) of the beam cross section, the mask 5 The length dimension in the long side direction (Y-axis direction) is configured to change stepwise along the way. In other words, this mask 5 is a mask 5 provided so as to shield the end in the long side direction in the beam cross section of the ion beam IB having a substantially rectangular beam cross section in the cross section orthogonal to the beam traveling direction, Two rectangles, each having a different long side, are arranged side by side with the short sides aligned. Further, when viewed from the beam traveling direction, the stepped portion of the mask 5 is arranged so as to be included in the short side of the beam cross section of the ion beam IB. If the graph of the shielding amount of IB is drawn, it will change discontinuously in the center part. Note that the mask 5 of the present embodiment has a shape in which two rectangular portions having different long side lengths are formed on a staircase. For example, two square portions or one square portion and You may make the shape which combined the one rectangular part.

  That is, the mask 5 extends from one short side of the beam cross section to the long side when viewed from the beam traveling direction of the ion beam IB as shown in FIG. A first shielding part 51 that shields a part of the first shielding part 51 extends in the long side direction from one short side of the beam cross section, and is provided side by side in the short side direction in the beam cross section with respect to the first shielding part 51. And a second shielding part 52 that shields a part different from the part shielded by the first shielding part 51 at the end of the ion beam IB. The shielding amount of the ion beam IB by the first shielding portion 51 and the shielding amount of the ion beam IB by the second shielding portion 52 are different from each other.

  More specifically, the first shielding part 51 and the second shielding part 52 are formed in a substantially rectangular shape, and can be shielded by appropriately adjusting the dimension in the long side direction and the dimension in the short side direction in the beam cross section. The amount is adjusted. Further, these dimensions and ratios are set based on the target dose that should be irradiated when the substrate W passes through this end.

  In the following description, for the sake of simplicity, the smaller shielding area is referred to as the first shielding part 51 and the larger shielding amount is referred to as the second shielding part 52.

  Next, these features will be described by describing in detail the design method of the shape of the mask 5, particularly the dimensions of the first shielding part 51 and the second shielding part 52.

  First, consider a case where the conventional rectangular masks 6 (a) and 6 (b) shape the portions where the ion beams IB (a) and IB (b) overlap. In other words, a state in which there is no change when the change in the shielding amount of the ion beams IB (a) and IB (b) is observed along the short side direction (X-axis direction) in the beam cross section is considered as an example. Here, as shown in FIG. 3, the outside of the position separated from the beam cross-sectional center of the ion beams IB (a) and IB (b) by DLT1 is shielded by the rectangular masks 6 (a) and 6 (b). Suppose that The DLT 1 is determined in this example so that the mask start positions of the ion beams IB (a) and IB (b) are substantially the same in the vertical direction, but the ion beams IB (a) and IB ( The shielding start position in b) may be different. Further, in this embodiment, the center of the ion beam IB is taken as a reference position in order to define the length dimension in the long side direction in the beam cross section of the first shielding part 51 and the second shielding part 52. The center position of the substrate W irradiated with the beam IB may be set as the reference position.

  Next, the current distribution (beam profile) when the two ion beams IB (a) and IB (b) in such a state are added is calculated. An example of the calculation result is shown in FIG. As shown in the graph of FIG. 4, in this example, since the shielding amount at the ends of the two ion beams IB (a) and IB (b) is small, the overlapping portion is also large. Accordingly, the portion where the end portions overlap has a larger current value than the other portions, and the irradiation amount (dose amount) of ions irradiated onto the substrate W is larger than the allowable upper limit with respect to the target value (overdose). ). Hereinafter, the width of the range that exceeds the allowable upper limit or lower limit of the reference value that is the target irradiation amount is referred to as a transition region width. In this embodiment, ± 10% of the reference value is set as the allowable upper limit value and the allowable lower limit value.

  Further, the position of the rectangular masks 6 (a) and 6 (b) is changed, and the beam profile is obtained by the same calculation. More specifically, as shown in FIG. 5, the mask start position is set to the center of the ion beams IB (a) and IB (b) so as to increase the shielding amount by the rectangular masks 6 (a) and 6 (b). Let us consider a case where DLT2 is brought closer to the center side of the ion beam IB. In this case, since the overlapping portions of the rectangular masks 6 (a) and 6 (b) and the ion beams IB (a) and IB (b) become small, as shown in the calculation result of FIG. The lower convex portion is formed smaller than the other portions and smaller than the allowable lower limit. That is, the irradiation amount (dose amount) irradiated to the substrate W is also reduced.

  The difference in beam profile due to the difference in the mask position of the rectangular mask 6 in FIGS. 4 and 6 can be explained by a schematic diagram as shown in FIG.

  That is, the beam profile along the long side direction of the ribbon-like ion beam IB ideally has a Gaussian distribution, but the mask position is set to DLT1, and the amount of shielding by the rectangular mask 6 is small. As shown in FIG. 7, since the irradiation amount at the end portion hardly decreases, the overlapping portion is excessively strong, so that in the added beam profile, a convex portion exceeding the allowable upper limit is formed in the central portion. . On the other hand, when the mask position is set to DLT2 and the shielding amount is increased, the irradiation amount at the center portion becomes too small, so that in the added beam profile, a convex portion lower than the allowable lower limit is formed at the center portion.

  From the above calculation, it can be seen that overdose or underdose occurs in the center of the rectangular mask 6 alone.

  Therefore, the mask 5 of the present embodiment has the first shielding portion 51 and the second shielding portion 52 cancel each other of the overdose portion and the underdose portion, so that the entire range of the beam is within an allowable range with respect to the reference value. The dimensions are configured to enter.

  More specifically, the first length dimension, which is the length dimension in the long side direction in the beam cross section of the first shielding portion 51, is DLT1, and the length dimension in the long side direction in the beam section of the second shielding portion 52 is. In the case of DLT2, by adjusting the ratio of the width dimension in the short side direction in each beam cross section, the overdose part and the underdose part cancel each other out so that the beam profile is within the allowable range with respect to the reference value. is there.

  That is, when the mask 5 having a stepped tip portion as in the present embodiment is used, the two ion beams IB shielded by the rectangular masks 6 having different mask positions in the long-side direction in the beam cross-section are the beam cross-sections. It can also be considered that they are arranged in parallel in the short side direction. Therefore, when the length dimensions of the first shielding part 51 and the second shielding part 52 are determined, the beam profiles weighted according to the ratio of the short side direction in the beam cross section can be superimposed.

  In the present embodiment, as shown in FIG. 8, the first width dimension DLT1W which is the width dimension in the short side direction in the beam section of the first shielding part 51 and the width dimension in the short side direction in the beam section of the second shielding part 52. As for the second width dimension DLT2W that is, the same value is set to 1: 1. That is, when the width dimension in the short side direction in the beam cross section of the ion beam IB is IBW, DLT1W = DLT2W = IBW / 2 is set.

  The beam profiles calculated in FIGS. 4 and 6 are the calculation results when the entire width of the ion beam IB is shielded when the width dimension of the ion beam IB is IBW. Therefore, the ion beam IB having a width dimension of IBW / 2 is irradiated. In this case, the dose at each point is ideally halved. Therefore, the beam profile in the case of using the mask 5 of the present embodiment can be calculated by multiplying the calculation results of FIGS. 4 and 6 by 1/2 and adding them, and as a result, as shown in the graph of FIG. It becomes a beam profile. As apparent from FIG. 9, it can be seen that the overdose portion and the underdose portion cancel each other, so that a substantially uniform profile is obtained over the entire overlapping portion. That is, it can be seen that the irradiation amount with respect to the central portion of the substrate W can be made more uniform.

  In this example, when the length dimension in the long side direction in the beam cross section of the first shielding part 51 and the second shielding part 52 is a combination of DLT1 and DLT2, the beam of the first shielding part 51 and the second shielding part 52 is used. Although the beam profile could be kept within the allowable range by setting the ratio of the width dimension in the short side direction in the cross section to 1: 1, depending on how to take DLT1 and DLT2, the first shielding part 51 and The width dimension in the short side direction in the beam cross section of the second shielding part 52 may be set so as to obtain a desired target dose uniformity. Furthermore, in this example, the masks 5 (a) and (b) provided in the ion beam supply apparatuses 11 (a) and 11 (b) have the same shape, and the first shielding part 51 and the second shielding part 52 are provided. The length dimensions DLT1 and DLT2 in the long side direction of the beam cross section and the width dimensions DLT1W and DLT2W in the short side direction of the beam cross section are all made the same in the masks 5 (a) and 5 (b). However, the length dimensions DLT1, DLT2 and the width dimensions DLT1W, DLT2W may be different between the mask 5 (a) and the mask 5 (b). That is, the mask position is different between the ion beam supply device 11 (a) and the ion beam supply device 11 (b), and the dimension in the length direction and the width dimension in the beam cross section may be different in each shielding part. Absent.

  As described above, according to the mask 5 and the ion beam irradiation apparatus 100 of the present embodiment, the mask 5 can freely set the length dimension in the long side direction and the width dimension in the short side direction in the beam section. Since the first shielding part 51 and the second shielding part 52 are formed side by side in the short side direction in the beam cross section, the first shielding part 51 and the second shielding part can be obtained by changing these dimensions. It is possible to freely adjust the shape of the beam profile formed by 52 and the addition ratio thereof. Therefore, these two freely adjusted aspects of different beam profiles can be added together, making it easy to bring the final added beam profile within a desired tolerance. In other words, since there was conventionally only one adjustment parameter that can change the beam profile, that is, the irradiation amount, it was difficult to perform precise adjustment. Since the first shielding part 51 and the second shielding part 52 having different shapes are provided, a plurality of adjustment parameters can be obtained, and the beam profile can be freely shaped. Therefore, it is possible to easily adjust such that the irradiation amount of the ion beam IB irradiated to the central portion of the substrate W has the same degree of uniformity as the other portions as in this embodiment.

  A modification of this embodiment will be described.

  In the embodiment, the mask 5 is used for the purpose of improving the uniformity of the overlapping portion when two ion beams IB are arranged one above the other. However, for example, one ion beam as shown in FIG. In order to reduce the width of the divided band W2 in the case of performing multiple chamfering by forming the plurality of cell regions W1 on the substrate W by changing the irradiation position of the IB on the substrate W, the mask 5 of the above embodiment. May be used. That is, the mask 5 of the above-described embodiment is provided at both ends of the ion beam IB, and the irradiation amount of the portion to be the cell region among the portions irradiated with the end portions of the ion beam IB on the substrate W is within the allowable range. And the dimensions of the first shielding part 51 and the second shielding part 52 may be determined so that the transition region width is within the width of the dividing band. In addition to the applications described above, the mask 5 of the present invention can be used to adjust the irradiation amount at the end in the long side direction in the beam cross section of the ion beam IB to a desired value or size.

  In the above-described embodiment, the stepped mask 5 is disposed at each end of each of the two ion beams IB. However, depending on the required accuracy, only one ion beam IB has a stepped end. The mask 5 may be used, and the other side may be a rectangular mask 6 or a mask 5 whose tip is inclined. Moreover, the shape of the 1st shielding part 51 and the 2nd shielding part 52 is not restricted to a rectangular shape, For example, the 1st shielding part 51 has an inclination in a front-end | tip part, and the 2nd shielding part 52 is a rectangular shape combination. It does not matter if you use it. In addition, the tip portions of the first shielding portion 51 and the second shielding portion 52 have different inclinations, and when the mask 5 is viewed along the short side direction in the beam cross section, the tip portions are halfway. The slope may change discontinuously. In short, the shape and size of the first shielding portion 51 and the second shielding portion 52 are different, and the amount of shielding is different, so that a desired beam profile can be obtained by superimposing different beam profiles. Any mask 5 may be used.

  In the embodiment, the first shielding portion 51 and the second shielding portion 52 are formed by making the shape of the tip portion of one mask 5 stepped, but for example, a plurality of mask members 5a and 5b are used. The first shielding part 51 and the second shielding part 52 may be formed. More specifically, as shown in FIG. 10, two mask members 5a and 5b are arranged along the traveling direction of the ion beam IB, and when viewed from the traveling direction, any one of the mask members 5a, What is necessary is just to make it have the part which 5b overlaps with the other mask members 5b and 5a. In such a case, it is only necessary to arrange two general-purpose masks in a rectangular shape without processing one mask into a complicated shape such as a staircase, and it is easy to manufacture. Furthermore, even if it is such, the effect similar to the said embodiment can be acquired.

  Further, as shown in FIG. 10A, the mask members 5a and 5b may be configured to be independently movable in the long side direction in the beam cross section by a driving mechanism such as a motor M. That is, you may enable it to adjust the length dimension of the long side direction in the beam cross section of the 1st shielding part 51 and the 2nd shielding part 52 each independently. If this is the case, the degree of freedom of adjustment can be further increased as compared with the above-described embodiment. For example, even when the irradiation position of the ion beam IB is shifted in the long side direction in the beam cross section, the adjustment is appropriately performed and always uniform. It is possible to irradiate the substrate W with the ion beam IB that is maintained in its property.

  Further, the moving direction is not limited to the long side direction in the beam cross section, and the mask 5 may be configured to move in the short side direction in the beam cross section. In addition, the mask 5 may be configured to move in both the long side direction and the short side direction in the beam cross section.

  Although the mask 5 of the above embodiment has two shielding portions, it may have a larger number of shielding portions. That is, the mask 5 may be a combination of three or more rectangular shielding portions as shown in FIGS. 11 (a) and 11 (b). As described above, if the mask 5 has a large number of shielding portions, it is possible to further improve the adjustment accuracy of the dose distribution in the overlapping portion of the ion beam IB.

  For example, when the mounting position is deviated from the original position when the electrodes of the ion source of the ion beam supply devices 11 (a) and 11 (b) are replaced during maintenance, the trajectory of the ion beam IB also changes. There is. When the irradiation position of the ion beam IB is shifted in the short side direction in the beam cross section, the shielding amount is not changed even if the arrangement of the mask 5 is not changed, and the profile of the ion beam IB at the end is substantially reduced. When the mask 5 is viewed from the beam traveling direction of the ion beam IB as shown in FIGS. 12A and 12B, the mask 5 has one of the beam cross sections. A third shielding portion 53 that extends in the long side direction of the beam cross section and is arranged in the short side direction of the beam cross section so as to sandwich the second shielding portion 52 with the first shielding portion 51. In addition, a first length dimension that is a length dimension in the long-side direction in the beam section of the first shielding part 51 and a third dimension that is a length dimension in the long-side direction in the beam section of the third shielding part 53 are provided. length A law may be respectively set to the same value.

  In such a case, as shown in FIG. 12, even if the irradiation position of the ion beam IB is shifted in either one of the short side directions of the beam cross section, the first shielding part 51 or the third shielding part 53 decreases. Since the amount of shielding performed increases directly in the third shielding unit 53 or the first shielding unit 51, the total shielding amount does not change. Therefore, the beam profile at the end is also kept in its original state, and it is possible to prevent the irradiation amount from changing.

  As shown in FIGS. 12A and 12B, the length dimension in the long side direction in the beam cross section of the second shielding portion 52 may be larger than that of the first shielding portion 51 and the third shielding portion 53. It does n’t matter if it ’s small. In short, it is only necessary to have different length dimensions.

  When the irradiation position of the ion beam is shifted in the short side direction in the beam cross section, the irradiation angle of the ion beam with respect to the mask may be changed. In order to prevent the beam profile from being changed due to the change in the irradiation angle, and the uniformity or the like cannot be maintained, the mask may be configured to be rotatable about the axis extending in the long side direction in the beam cross section. If it is such, it becomes possible to adjust so that an irradiation angle may always become the same state, and it can avoid being influenced by the fluctuation | variation of an irradiation angle.

  The ion beam irradiation apparatus of the present invention is a concept including various uses such as an ion implantation apparatus, an ion doping apparatus, an ion beam deposition apparatus, and an ion beam etching apparatus. In short, the present invention can be applied to any application in which the end of a ribbon-like ion beam is irradiated on the substrate or the overlapping of the ends becomes a problem. Further, the substrate is not limited to a semiconductor substrate, and may be a silicon wafer, a glass substrate, or a plate-like substrate irradiated with other ion beams.

  In addition, various modifications and combinations of embodiments may be performed without departing from the spirit of the present invention.

5: Mask 51: 1st shielding part 52: 2nd shielding part 53: 3rd shielding part 100: Ion beam irradiation apparatus IB: Ion beam W: Substrate

Claims (6)

An ion beam irradiation apparatus configured to irradiate an ion beam having a substantially rectangular beam cross section in a cross section perpendicular to the beam traveling direction onto a substrate having a dimension larger than the long side of the beam cross section. ,
A mask that shields the end in the long side direction in the beam cross section ,
When the mask is viewed from the beam traveling direction of the ion beam, the mask is
A first shielding portion that extends in a long side direction from one short side of the beam cross section and is provided to shield a part of the end of the ion beam;
It extends in the long side direction from one short side of the beam cross section and is provided side by side with the first shielding part in the short side direction of the beam cross section, and the first shielding part is shielded at the end of the ion beam. A second shielding part provided to shield a part different from the part to be
An ion beam irradiation apparatus , wherein an ion beam shielding amount by the first shielding portion and an ion beam shielding amount by the second shielding portion are different from each other. The ratio of the first width dimension which is the width dimension in the short side direction in the beam cross section of the first shielding part and the second width dimension which is the width dimension in the short side direction in the beam section of the second shielding part is the ion. The ion beam irradiation apparatus according to claim 1, wherein the ion beam irradiation apparatus is determined based on a target dose of the ion beam at the end of the beam. 3. The ion beam irradiation apparatus according to claim 1, wherein the first shielding part and the second shielding part have a substantially rectangular shape when viewed from the beam traveling direction of the ion beam . The first shielding part and the second shielding part are provided separately, and the first shielding part and the second shielding part partially overlap when viewed from the beam traveling direction of the ion beam. The ion beam irradiation apparatus according to claim 1. A first length dimension which is a length dimension in a long side direction in a beam section of the first shielding part, and a second length dimension which is a length dimension in a long side direction in a beam section of the second shielding part. The ion beam irradiation apparatus according to claim 1, wherein the ion beam irradiation apparatus is configured to be independently changeable. When the mask is viewed from the beam traveling direction of the ion beam, the mask extends in the long side direction from one short side of the beam cross section and sandwiches the second shielding part with the first shielding part. A third shield provided side by side in the direction of the short side of the beam cross section;
A first length dimension that is a length dimension in the long side direction in the beam cross section of the first shielding part, and a third length dimension that is a length dimension in the long side direction in the beam section of the third shielding part. The ion beam irradiation apparatus according to claim 1, wherein the ion beam irradiation apparatuses are set to the same value.