CN-121985747-A - Irradiation treatment system for semiconductor local modification

CN121985747ACN 121985747 ACN121985747 ACN 121985747ACN-121985747-A

Abstract

The application relates to an irradiation treatment system for semiconductor local modification, and belongs to the technical field of semiconductor processing. The irradiation treatment system for the semiconductor local modification comprises a bearing table, a shielding mechanism, a positioning detection assembly and a control module, wherein the bearing table is used for bearing and fixing a semiconductor wafer, the shielding mechanism comprises a shielding plate and a driving assembly, a radiation port is formed in the shielding plate, the surface of the wafer facing a radiation source is a processing surface, the edge position of the shielding plate is fixed, the driving assembly is connected with the center point of the shielding plate and drives the center point to axially lift so as to enable the shielding plate to elastically deform to form an arc-shaped surface, the positioning detection assembly is used for detecting contact between the shielding plate and the processing surface, and the control module controls the lifting of the center point of the shielding plate according to a contact signal so as to enable the shape of the arc-shaped surface of the shielding plate to be matched with the arc-shaped shape of the processing surface. The irradiation treatment system for semiconductor local modification provided by the application can improve the reliability and the yield of the semiconductor local modification process.

Inventors

WANG WEI
LIANG YIXUAN
DENG ZHIYONG
XU CHENGCHENG
ZENG SONGBAI
MENG ZHONGHUA
TU XIAO
ZHANG MIN
HUI JUNJIE
DU YURAN

Assignees

成都中核高通同位素股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260407

Claims (10)

1. An irradiation treatment system for localized modification of a semiconductor, comprising: the bearing table is used for bearing and fixing the semiconductor wafer; The radioactive source is arranged above the bearing table; The shielding mechanism is positioned between the bearing table and the radioactive source and comprises a shielding plate and a driving assembly, and a radiation port is formed in the shielding plate; the surface of the wafer facing the radiation source is a processing surface and comprises a region to be modified and a non-modified region, wherein the radiation port is arranged corresponding to the region to be modified; the edge of the shielding plate is fixed, the driving assembly is connected to the center point of the shielding plate and used for driving the center point to lift along the axis direction of the shielding plate, so that the shielding plate is elastically deformed to form an arc-shaped surface facing or deviating from the wafer; a positioning detection assembly for detecting contact between the shielding plate and the processing surface; And the control module is used for controlling the driving assembly to drive the central point of the shielding plate to lift according to the contact signal acquired by the positioning detection assembly, so that the shape of the arc-shaped surface of the shielding plate is matched with the arc-shaped shape of the processing surface.
2. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 1, The shielding mechanism further comprises a movable module, and the movable module is connected with the edge of the shielding plate and used for driving the shielding plate to lift along the axial direction so that the shielding plate is close to or far away from the wafer.
3. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 2, The positioning detection assembly comprises a first sensor and a plurality of second sensors; The first sensor is arranged at the center point of the shielding plate; the second sensors are arranged at the edge of the shielding plate and are circumferentially arranged at intervals around the first sensor; The second sensor is used for detecting whether the edge of the shielding plate is contacted with the edge of the wafer or not when the shielding plate is driven by the movable module to approach the wafer; The first sensor is used for detecting whether the center point is in contact with the wafer or not when the driving assembly drives the center point to move towards the wafer.
4. A radiation treatment system for localized modification of a semiconductor as defined in claim 3, The moving path of the center point is provided with a first limit position and a second limit position; When the center point is located at the first limit position, the shielding plate is arched away from the wafer; When the center point is located at the second limit position, the shielding plate arches towards the wafer; The control module is used for executing positioning operation before irradiation starts, wherein the control module is used for controlling the movable module to drive the shielding plate to move towards the wafer until all the second sensors detect contact signals, and controlling the center point to move from the first limit position towards the second limit position until the first sensors detect contact signals.
5. A radiation treatment system for localized modification of a semiconductor as defined in claim 3, The shielding mechanism further includes a connector extending along the axis; the center of the connecting piece is positioned on the axis, the connecting piece is connected with the edge of the shielding plate, and the connecting piece is provided with a mounting groove for accommodating the driving assembly.
6. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 5, The driving assembly comprises a driving power supply, piezoelectric ceramics and an elastic piece; The piezoelectric ceramic is connected to the output end of the driving power supply; the elastic piece is connected between the bottom wall of the mounting groove and the shielding plate, and pulls the shielding plate through self elasticity so that the center point is abutted with the end part of the piezoelectric ceramic; the piezoelectric ceramic stretches and contracts along the axis direction under the drive of the driving power supply so as to push the center point to move relative to the edge of the shielding plate.
7. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 6, The piezoelectric ceramic extends out of the mounting groove towards one end of the shielding plate; in the axial direction, when the piezoelectric ceramic contracts to the shortest, the center point is located at the first limit position; when the piezoelectric ceramic stretches to the longest, the center point is located at the second limit position.
8. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 5, The shielding mechanism further comprises a rigid annular support base, wherein the support base is connected to the edge of the shielding plate; the support base is connected with the connecting piece through a plurality of reinforcing ribs; The movable module is connected with the shielding plate through the supporting base.
9. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 8, The plurality of reinforcing ribs are circumferentially arranged around the center point; The shielding plate is provided with a plurality of weakening areas extending from the central point to the supporting base; The thickness of the weakening zone is smaller than the thickness of the rest area of the shielding plate; in the circumferential direction, the weakening areas are staggered with the reinforcing ribs, and the included angle between any weakening area and the adjacent reinforcing rib is a fixed value.
10. An irradiation treatment system for localized modification of a semiconductor as set forth in claim 1, A boss is arranged at the center point of the surface of the shielding plate, which is away from the wafer; A plurality of elastic supporting strips are arranged on the periphery of the boss; one end of each supporting bar is connected with the boss, the other end of each supporting bar is connected with the shielding plate, and the connecting point is positioned between the central point and the edge of the shielding plate; The support strips are circumferentially and uniformly distributed around the central point, the connection points of the support strips and the shielding plate are located on the same circumference, and the circle center of the circumference coincides with the central point.

Description

Irradiation treatment system for semiconductor local modification Technical Field The application relates to the technical field of semiconductor processing, in particular to an irradiation treatment system for semiconductor local modification. Background In semiconductor device fabrication and packaging processes, it is often necessary to modify specific localized areas of a semiconductor wafer, such as by irradiating (e.g., ion implantation, electron beam, laser, etc.) a material to change its electrical properties, lattice structure, or stress state. Such processing typically requires that the processing be performed precisely only within a predetermined "area to be modified" (e.g., the area where the conductive vias, isolation regions, or functional elements are formed in the future), while leaving the properties of the "non-modified area" (e.g., the existing circuitry, electrodes, or sensitive structures) unaffected. To achieve this selective treatment, the prior art generally employs a shadow mask (shielding) in combination with a radiation source. Specifically, a shielding plate with a specific opening (radiation port) is arranged between a carrying table carrying a wafer and a radiation source. The position and shape of the radiation port are designed according to the pattern of the area to be modified on the processing surface of the wafer, and ideally, the radiation rays passing through the radiation port should be strictly limited in the area to be modified, so as to protect the non-modified area. However, in practice it has been found that the processing surface of the semiconductor wafer (i.e. the surface that receives the irradiation) is not always an ideal geometrical plane. The wafer surface may exhibit small curvature (protrusions or depressions) in whole or in part due to the effects of internal stress in the material, previous process steps (e.g., film deposition, chemical mechanical polishing), or the three-dimensional structural design of the device itself. When a conventional flat shutter is used, there is a mismatch gap between it and the wafer surface having the curvature. Such voids can cause a series of serious problems. In one aspect, the position of the radiation ports on the shield is designed based on a flat surface. When the surface of the wafer is arc-shaped, the projection position of the ray irradiated on the actual curved surface is offset, so that the actual position of the area to be modified deviates from preset coordinates, and the alignment and the function of the device are affected. On the other hand, due to scattering of radiation rays in the void and variation in incident angle, the irradiation pattern size irradiated onto the curved wafer may be larger than the design size of the radiation port, and edge definition may be degraded (edge blurring). This may lead to widening of the boundary transition region between the modified and non-modified regions, even with unintended overlapping irradiation, compromising isolation of the device or definition of the functional region. On the other hand, for an arc-shaped surface, the radiation incidence angle is different, which may cause the received radiant energy (dose) in unit area to be inconsistent, and affect the uniformity of the modification effect. Therefore, there is a need for an irradiation processing system capable of adapting the shape of the shielding plate to the shape of the curved surface of the processing surface of the wafer in real time, so as to control the definition of the boundary and the position accuracy of the irradiation pattern, thereby improving the reliability and the yield of the semiconductor local modification process. Disclosure of Invention The present application has been made in view of the above problems, and an object of the present application is to provide an irradiation treatment system for semiconductor local modification, which can improve the reliability and yield of the semiconductor local modification process, and improve the above problems. The application is realized by the following technical scheme: The application provides an irradiation treatment system for semiconductor local modification, which comprises a bearing table, a radioactive source, a shielding mechanism, a positioning detection assembly and a control module, wherein the bearing table is used for bearing and fixing a semiconductor wafer, the radioactive source is arranged above the bearing table, the shielding mechanism is arranged between the bearing table and the radioactive source and comprises a shielding plate and a driving assembly, a radiation opening is formed in the shielding plate, the surface of the wafer facing the radioactive source is a processing surface and comprises a region to be modified and a non-modified region, the radiation opening is arranged corresponding to the region to be modified, the edge position of the shielding plate is fixed, the driving assembly is connected to the center p