Plasma disruption protection apparatus and method

Abstract

The present application provides a plasma damage protection device and a protection method. The plasma damage protection device is disposed in an integrated circuit. The plasma damage protection device includes a switch component and a transmission structure. The switch component is coupled between a reference power rail and a pad. The switch component is turned on or off according to a charge on the pad, wherein the pad is coupled to a protected component. The transmission structure is used to transmit the charge on the pad to a control terminal of the switch component in a back-end-of-line process. In the back-end-of-line process, the switch component is turned on according to the charge on the pad.

Description

Technical Field

[0001] This invention relates to a plasma damage protection device and method, and more particularly to a plasma damage protection device and method capable of achieving bidirectional polarity protection. Background Technology

[0002] In semiconductor manufacturing, processes such as etching often require the application of plasma to integrated circuits. The charge generated by this plasma can accumulate in the circuit components and cause damage.

[0003] In known technologies, diodes are often placed near the protected component to provide protection against plasma damage. These diodes typically only protect against charges of a single polarity. Therefore, known technologies also utilize bipolar transistors to achieve bipolar plasma damage protection. However, plasma damage protection achieved through bipolar transistors is inadequate in protecting against both positive and negative charges. Therefore, developing a high-performance plasma damage protection device is an important task for designers in this field. Summary of the Invention

[0004] This invention relates to a plasma damage protection device and method, which can improve the protection effectiveness against plasma damage generated in the process.

[0005] According to an embodiment of the present invention, a plasma damage protection device is disposed in an integrated circuit. The plasma damage protection device includes a switching component and a transmission structure. The switching component is coupled between a reference power rail and a solder pad. The switching component is turned on or off based on the charge on the solder pad, wherein the solder pad is coupled to the protected component. The transmission structure is used to transfer the charge on the solder pad to a control terminal of the switching component in a subsequent process. In the subsequent process, the switching component is turned on based on the charge on the solder pad.

[0006] According to an embodiment of the present invention, the plasma damage protection method includes: forming a transmission structure to be coupled to a solder pad; forming a switching assembly to be coupled to the transmission structure, the protected component, the solder pad, and a reference power line; and, in a subsequent process, causing the transmission structure to transmit the charge on the solder pad to a control terminal of the switching assembly, and causing the switching assembly to be turned on according to the charge on the solder pad.

[0007] Based on the above, this invention provides a transmission structure in the back-end process to transfer the charge on the solder pads to the control terminal of the switching component, and discharges the charge on the solder pads by turning on the switching component. This also prevents damage to components in the integrated circuit from the charge accumulated on the solder pads, maintaining the reliability of the integrated circuit. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of a plasma damage protection device according to an embodiment of the present invention;

[0009] Figure 2 This is a schematic diagram of a plasma damage protection device according to another embodiment of the present invention;

[0010] Figure 3A as well as Figure 3B For the present invention Figure 2 A schematic diagram illustrating the operation mode of the plasma damage protection device 200 in this embodiment;

[0011] Figure 4 This is a schematic diagram of a plasma damage protection device after the downstream process according to an embodiment of the present invention;

[0012] Figure 5 This is a flowchart of a plasma damage protection method according to an embodiment of the present invention.

[0013] Explanation of icon numbers

[0014] 100, 200, 400: Plasma damage protection devices;

[0015] 110, 210, 410: Switching components;

[0016] 120, 220, 420: Transmission structure;

[0017] 130, 230: Connection structure;

[0018] 140, 240, 440: Transmission wires;

[0019] ML, M1, M2: Metal layers;

[0020] PC: Protected Component;

[0021] PD1, PD2: solder pads;

[0022] RPWL: Reference power rail;

[0023] S510~S530: Plasma damage protection procedures;

[0024] T1: Transistor. Detailed Implementation

[0025] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element references are used in the drawings and description to denote the same or similar parts.

[0026] Please refer to Figure 1The plasma damage protection device 100 includes a switching assembly 110 and a transmission structure 120. The switching assembly 110 is coupled between a reference power rail RPWL and a solder pad PD1. The switching assembly 110 is turned on or off according to the charge on the solder pad PD1, which is coupled to a protected component PC. The protected component PC may be a transistor or other type of semiconductor component. The transmission structure 120 is coupled to the switching assembly 110 and the reference power rail RPWL. In this embodiment, the transmission structure 120 may be coupled to the solder pad PD1 via a connection structure 130.

[0027] In this embodiment, during the back-end-of-line (BEoL) process, the transmission structure 120 is maintained coupled to the pad PD1 via the connection structure 130, allowing the charge on the pad PD1 to be transferred to the control terminal of the switching assembly 110 via the transmission structure 120. The switching assembly 110 is a transistor T1. The first terminal of transistor T1 is connected to the pad PD1, and the second terminal and base terminal of transistor T1 are coupled to the reference power rail RPWL. The control terminal of transistor T1 is coupled to the transmission structure 120.

[0028] It is worth mentioning that the switching assembly 110 can be turned on or off based on the charge on the solder pad PD1. Specifically, when the charge accumulated on the solder pad PD1 by the applied plasma during the process exceeds a predetermined amount, the switching assembly 110 can be turned on to discharge the charge on the solder pad PD1 to the reference power rail RPWL, thus preventing damage to the protected component PC due to excessive charge on the solder pad PD1.

[0029] Incidentally, the reference power rail RPWL can be coupled to pad PD2. The reference power rail RPWL can receive a reference voltage through pad PD2.

[0030] Furthermore, in this embodiment, the connection structure 130 can be removed after the downstream process is completed. A transmission line 140 can be formed between the control terminal of the switching assembly 110 and the reference power rail RPWL. The transmission line 140 is used to pull the voltage at the control terminal of the switching assembly 110 down to the reference voltage on the reference power rail RPWL. In this way, the transistor T1 in the switching assembly 110 can remain in a turned-off state.

[0031] Please refer to Figure 2The plasma damage protection device 200 includes a switching assembly 210 and a transmission structure 220. The switching assembly 210 is constructed from a transistor T1. The transistor T1 is coupled between a pad PD1 and a reference power rail RPWL, and the control terminal of the transistor T1 is coupled to the transmission structure 220. In this embodiment, the pad PD1 is composed of a metal layer ML, wherein the metal layer ML is coupled to metal layers M1 and M2, and the metal layer M1 is directly connected to the transistor T1 and the protected component PC.

[0032] Furthermore, the transmission structure 220 is formed in at least one metal layer. In one embodiment, the transmission structure 220 may be formed from metal layers ML, M2, and M1. The metal layers ML, M2, and M1 are coupled sequentially. Moreover, before subsequent processes are completed, the transmission structure 220 can be coupled to the pad PD1 via a connection structure 230. The connection structure 230 may be constructed using the same metal layers ML, M2, and M1 as the transmission structure 220.

[0033] In the subsequent process, the charge on the solder pad PD1 can be conducted to the control terminal of the transistor T1 through the connection structure 230 and the transmission structure 220. If the charge on the solder pad PD1 exceeds a certain threshold, the transistor T1 can be turned on accordingly, forming a conduction path between the solder pad PD1 and the reference power rail RPWL. Through the conduction path provided by the transistor T1, the charge on the solder pad PD1 can be effectively discharged, preventing damage to the protected component PC due to the charge on the solder pad PD1.

[0034] In this embodiment, the reference power rail RPWL is coupled to the pad PD2 and can receive a reference voltage.

[0035] On the other hand, once the downstream process is completed, the connection structure 230 can be removed, and a transmission line 240 can be formed between the control terminal of transistor T1 and the reference power rail RPWL. The transmission line 240 is used to transmit the reference voltage on the reference power rail RPWL to the control terminal of transistor T1, and to keep transistor T1 in the off state.

[0036] Incidentally, in this embodiment, there is no fixed limitation on the number of metal layers forming the solder pad PD1, the connection structure 230, and the transmission structure 220. Figure 2 These are merely illustrative examples and are not intended to limit the scope of the invention.

[0037] In addition, transistor T1 can be an N-type gold oxide semiconductor field-effect transistor.

[0038] Reference Figure 3AWhen the plasma applies a positive charge that remains on the solder pad PD1, the positive charge on the solder pad PD1 can be transferred to the control terminal of the transistor T1 via the interconnection structure 230 and the transmission structure 220, which are interconnected through the metal layer ML. Since the transistor T1 is an N-type transistor, it can be turned on based on the positive charge on its control terminal. Under these conditions, the turned-on transistor T1 forms a channel between the solder pad PD1 and the reference power rail RPWL, allowing the charge on the solder pad PD1 to be discharged through the channel formed by the transistor T1 via its second terminal.

[0039] In this way, excessive positive charge will not accumulate on the gate terminal of the protected component PC (such as a transistor), which can effectively reduce the possibility of the protected component PC being burned out and maintain the normal operation of the integrated circuit.

[0040] Please note that during the fabrication of metal layer M1, the solder pad PD1, the connection structure 230, and the transfer structure 220 are interconnected. After metal layer M1 is fabricated and the process for metal layer M2 begins, a portion of metal layer M1 in the connection structure 230 can be removed, disconnecting the solder pad PD1 and the metal layer M1 in the transfer structure 220. Similarly, during the fabrication of metal layer M2, the solder pad PD1, the connection structure 230, and the transfer structure 220 are interconnected. After metal layer M2 is fabricated and the process for metal layer M2 begins, a portion of metal layer M2 in the connection structure 230 can be removed, disconnecting the solder pad PD1 and the metal layer M2 in the transfer structure 220.

[0041] Reference Figure 3B When the plasma applies a negative charge that remains on the solder pad PD1, the negative charge on the solder pad PD1 can be transferred to the control terminal of the transistor T1 via the interconnection structure 230 and the transmission structure 220, which are interconnected through the metal layers ML. Since the transistor T1 is an N-type transistor, its first terminal has an N-type heavily doped region (N+), and the transistor T1 may have a P-type well region at its base. Therefore, when the control terminal of the transistor T1 receives a negative charge, the PN junction between the base terminal and the first terminal of the transistor T1 can be turned on, forming a channel. Under these conditions, the negative charge on the solder pad PD1 can be discharged through the channel formed by the transistor T1 and through the base terminal of the transistor T1, preventing the protected component PC from being burned out due to the accumulated negative charge on its gate terminal.

[0042] Depend on Figure 3A as well as Figure 3BAs can be seen from the implementation method, the plasma damage protection device 200 can effectively provide a path for the discharge of charges, whether positive or negative charges generated by the plasma, and achieve the purpose of plasma damage protection.

[0043] Reference Figure 4 In the integrated circuit, after the back-end process is completed, the plasma damage protection device 400 includes a switching assembly 410, a transmission structure 420, and a transmission line 440. The switching assembly 410 includes a transistor T1. The transistor T1 can be an N-type transistor, coupled between a reference power rail RPWL and a pad PD1. The control terminal of the transistor T1 is coupled to the transmission structure 420 and the transmission line 440. The transmission line 440 connects the reference power rail RPWL and the transmission structure 420. When the reference power rail RPWL receives a reference voltage (e.g., a reference ground voltage), the transmission line 440 transmits the reference voltage to the control terminal of the transistor T1. Under this condition, the transistor T1 can be turned off according to the received reference voltage.

[0044] It is worth mentioning that in this embodiment, the solder pad PD1 and the transmission structure 420 are physically isolated from each other. After the subsequent processing is completed, the connection structure used to connect the solder pad PD1 and the transmission structure 420 has been removed. In this way, when the integrated circuit is operating normally, the voltage applied to the solder pad PD1 is not affected by the transmission structure 420 and the transistor T1, so that the protected component PC can maintain normal operation.

[0045] Figure 5 This is a flowchart of a plasma damage protection method according to an embodiment of the present invention. In step S510, a transmission structure is formed in the integrated circuit to couple to the solder pads. In step S520, a switching component is formed to couple to the transmission structure, the protected component, the solder pads, and the reference power line. Next, in step S530, in a subsequent process, the transmission structure transmits the charge on the solder pads to the control terminal of the switching component, and the switching component is turned on according to the charge on the solder pads. When the switching component is turned on, the charge on the solder pads can be discharged through the turned-on switching component, effectively preventing the protected component in the integrated circuit from being damaged by the accumulated charge on the solder pads.

[0046] The implementation details of the above steps have been described in detail in the aforementioned embodiments, and will not be repeated here.

[0047] In summary, the plasma damage protection device of the present invention provides a transmission structure to transfer the charge on the solder pads in the later stages of the process, and provides a switching component to be turned on according to the charge on the solder pads transferred by the transmission structure. Through the turned-on switching component, the accumulated charge on the solder pads can be effectively discharged, achieving the plasma damage protection action. In the embodiments of the present invention, the switching component can be turned on according to any polarity of charge, achieving the effect of bidirectional polarity protection. It is worth mentioning that after the later stages of the process are completed, the plasma damage protection device of the present invention can disconnect the connection between the transmission structure and the solder pads, ensuring that the plasma damage protection device does not affect the normal operation of the integrated circuit.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plasma damage protection device, disposed in an integrated circuit, characterized in that, include: A switching assembly, coupled between a reference power rail and a solder pad, is turned on or off according to the charge on the solder pad, wherein the solder pad is coupled to a protected component. as well as A transmission structure is provided for transferring the charge on the solder pads to the control terminal of the switching assembly during subsequent processes. In the subsequent process, the switching assembly is turned on based on the charge on the solder pads. A transmission line is used to connect between the reference power rail and the control terminal of the switching assembly after the downstream process. The transmission line is used to transmit a reference ground voltage to the control terminal of the switching assembly to turn off the switching assembly.

2. The plasma damage protection device according to claim 1, characterized in that, Also includes: A connection structure for connecting the solder pad and the transmission structure, wherein the connection structure is removed after the subsequent process.

3. The plasma damage protection device according to claim 1, characterized in that, The switching assembly includes: A transistor having a first terminal coupled to the pad, a control terminal coupled to the transmission structure, and a second terminal and a base terminal coupled to the reference power rail.

4. The plasma damage protection device according to claim 3, characterized in that, The transistor is an N-type transistor. When the charge on the pad is positive, the transistor is turned on according to the charge on the pad at the control terminal.

5. The plasma damage protection device according to claim 3, characterized in that, The transistor is an N-type transistor. When the charge on the pad is negative, the PN junction formed between the base terminal of the transistor and the first terminal of the transistor is turned on.

6. The plasma damage protection device according to claim 1, characterized in that, The transmission structure is formed in at least one metal layer.

7. A plasma damage protection method, characterized in that, include: Form a transmission structure to couple to the solder pad; A switching assembly is formed to couple to the transmission structure, the protected component, the pad, and the reference power rail; as well as In the subsequent process, the transmission structure transmits the charge on the solder pad to the control terminal of the switching assembly, and the switching assembly is turned on according to the charge on the solder pad; After the subsequent process, a transmission conductor is formed to connect the reference power rail to the switch; Between the control terminals of the components; as well as The reference ground voltage is transmitted to the control terminal of the switching assembly via the transmission line to turn off the switching assembly.

8. The plasma damage protection method according to claim 7, characterized in that, Also includes: A connection structure is formed to connect the switching assembly and the transmission structure.

9. The plasma damage protection method according to claim 8, characterized in that, Also includes: The connection structure is removed after the subsequent process.

10. The plasma damage protection method according to claim 7, characterized in that, The switching component is a transistor, and the plasma damage protection method further includes: When the charge on the pad is positive, the transistor is turned on according to the charge on the pad at the control terminal.

11. The plasma damage protection method according to claim 10, characterized in that, Also includes: When the charge on the pad is negative, the PN junction formed between the base terminal of the transistor and the first terminal of the transistor is turned on.

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