Method for producing a semiconductor component, and micromirror assembly

Abstract

The invention relates to a method for producing a semiconductor component, in particular having microstructures. This involves firstly producing a semiconductor chip (99) having four lateral faces (104a, 104b, 104c, 104d) of the semiconductor chip (99) arranged perpendicularly to a principal plane of extent of the semiconductor chip (99). The semiconductor chip (99) comprises an outer frame structure (105) surrounding two adjacent lateral faces from among the four lateral faces (104a, 104b, 104c, 104d) of the semiconductor chip (99). The semiconductor chip (99) is connected to the outer frame structure (105) by means of at least three first springs (102a, 102b, 102c). Furthermore, the semiconductor chip (99) is moved to a next process step by means of a tool acting on the outer frame structure (105) of the semiconductor chip (99). Furthermore, the outer frame structure (105) and the three first springs (102a, 102b, 102c) are removed from the semiconductor chip (99).

Description

[0001] Description

[0002] Method for producing a semiconductor device and

[0003] The invention relates to a method for producing a semiconductor device. Furthermore, the invention relates to a micromirror array.

[0004] State of the art

[0005] Document DE 102 46 053 A1 describes a method for separating a substrate wafer into a number of substrate chips. First, the substrate wafer is temporarily bonded to a carrier wafer, and then the substrate chips are separated. A narrow base is provided between the substrate chip and the carrier wafer. The narrow base serves to hold the chips in a defined position until their final separation, whereby no great forces are required for the subsequent separation of the separated chips.

[0006] Based on this, it is an object of the present invention to develop a method for producing a semiconductor component with a stable and at the same time easily detachable connection between the semiconductor chip and the handling frame.

[0007] Disclosure of the invention

[0008] To achieve this object, a method for producing a semiconductor component according to claim 1 is proposed. Furthermore, a micromirror arrangement according to claim 15 is proposed.

[0009] In the method for producing a semiconductor component, in particular with microstructures, a semiconductor chip is first produced with four side surfaces arranged perpendicular to a main extension plane of the semiconductor chip. The produced semiconductor chip furthermore has an outer frame structure that surrounds two adjacent of the four side surfaces of the semiconductor chip. The outer frame structure is in particular L-shaped and thus only partially surrounds the semiconductor chip. The produced semiconductor chip is connected to the outer frame structure by means of at least three first springs. Furthermore, the semiconductor chip is moved to a next process step by means of a tool that acts on the outer frame structure of the semiconductor chip. The acting tool is in particular a vacuum gripper. Furthermore, the outer frame structure and the three first springs are removed from the semiconductor chip.Connecting the semiconductor chip to the outer frame structure as a handling surface creates a detachable yet stable connection. The semiconductor chip is preferably moved using a pick-and-place process by means of the tool engaging the outer frame structure of the semiconductor chip.

[0010] Preferably, the at least three first springs are designed as spiral tube springs, in particular as spiral Bourdon tubes. This results in a pneumatically detachable mechanical connection between the semiconductor chip and the outer frame structure.

[0011] Preferably, the semiconductor chip with the outer frame structure and the at least three first springs is structured from a wafer, in particular by means of an etching process. A MEMS manufacturing process is preferably used for this purpose. The wafer is preferably a silicon wafer. Preferably, a plurality of semiconductor chips are produced from the wafer. Preferably, at least four further second springs, in particular spiral tubular springs, are structured from the, in particular circumferential, wafer such that the semiconductor chip with the outer frame structure and the three first springs is connected to the wafer by means of the four second springs in a respective third position, in particular fastening position, of the second springs. Preferably, two of the second springs connect two, in particular free, side surfaces of the semiconductor chip and the two further second springs connect the two side surfaces of the outer frame structure to the wafer.Two of the second springs each engage a side surface, in particular a free one, of the semiconductor chip, and the two other second springs engage the outer frame structure. Subsequently, the tool, in particular the vacuum gripper, engages the outer frame structure to move the semiconductor chip to the next process step, and the semiconductor chip is separated from the wafer with the outer frame structure in a fourth position, in particular a separation position, of the four second springs.

[0012] Preferably, in a further process step, the semiconductor chip is treated in such a way that its outer surface, in particular its surface, is sensitive to mechanical stress. Furthermore, a coating, in particular a light-reflecting coating, is applied to the outer surface of the semiconductor chip, which is sensitive to mechanical stress. In this context, the outer frame structure protrudes upwards so that the sensitive outer surface is not damaged when the tool is applied.

[0013] Preferably, the outer frame structure is connected to the semiconductor chip solely by means of the at least three first springs. Accordingly, additional means for attaching the outer frame to the semiconductor chip are not necessary.

[0014] Preferably, the at least three first springs are patterned out of the wafer in such a way that a fixed end of each of the three first springs is connected to the outer frame structure. The fixed end of the first springs is accordingly located on the outer frame structure and does not require any space on the sensitive surface of the semiconductor chip.

[0015] Preferably, at least in a first position, in particular a fastening position, of the three first springs, a free end of each of the three first springs is arranged in a first recess in the semiconductor chip assigned to the respective first spring. This means that recesses are provided in the semiconductor chip for the free ends of the first springs, in which the springs are fastened in the respective first position. Preferably, the recesses are arranged in a plane that is different from the sensitive surface of the semiconductor chip. Preferably, the free ends of the three first springs are structured out of the wafer in such a way that they have a structure at the free end that, in interaction with the respective assigned first recess, serves to connect, in particular couple, to the semiconductor chip. In particular, the structure of the free ends of the first springs is a hook-shaped structure.Preferably, the first recesses for coupling to the respective free end also have a hook-shaped structure at the end. In contrast, the outer frame structure and the three springs are preferably separated from the semiconductor chip in a second position, in particular a separation position of the three springs. Here, the first springs are arranged in the second position in a second recess of the outer frame structure assigned to the respective spring. The first springs move accordingly from the first position in the first recess to the second position in the second recess and are arranged only on the outer frame structure in the second position. Thus, the outer frame can be separated without damaging the sensitive surface of the semiconductor chip.Preferably, the first springs are structured out of the wafer in such a way that two first springs, each arranged on the same side surface of the semiconductor chip, have opposing coils of the springs. This enables a secure connection of the outer frame to the semiconductor chip.

[0016] Preferably, the pressure within the first and / or second springs, in particular the spiral tube springs, is controlled via an air inlet at the fixed end of the respective first or second springs such that, in the first position of the first springs and / or the third position of the second springs, the ambient air pressure corresponds to the air pressure within the spiral tube springs. Furthermore, the pressure is controlled such that, in the second position of the first springs and / or the fourth position of the second spring, the air pressure within the spiral tube springs is lower than the ambient air pressure. This provides a pneumatic control option for the different positions of the springs.Preferably, the semiconductor chip and the surrounding frame are structured out of the wafer in such a way that the air inlets for the first springs are arranged on a first side of the wafer, in particular a top side of the outer frame structure, and the air inlets for the second springs are arranged on a second side of the wafer opposite the first side of the wafer, in particular a bottom side of the wafer. In this context, the tool, in particular the vacuum gripper, controls the pressure within the first springs when gripping the outer frame structure. In particular, the tool generates a negative pressure within the first springs during gripping. The tool can thus fulfill two functions at once.

[0017] Preferably, the semiconductor chip is moved to a substrate using the tool and subsequently connected to the substrate. After the generated outer frame structure and the first three springs have been removed from the semiconductor chip, another semiconductor chip is placed on the substrate using the tool. In particular, the additional semiconductor chip is placed directly next to the semiconductor chip using the tool. The additional semiconductor chip is, in particular, an identical semiconductor chip. The two semiconductor chips are accordingly designed, in particular, to be similar.

[0018] A further subject of the present invention is a micromirror array manufactured using the method described above. This array comprises a number of independently operable individual mirror elements arranged as a field, in particular an array, and each movable via an actuator, in particular actuator electrodes. The individual mirror elements each have a reflective surface.

[0019] Description of the drawings

[0020] Figure 1 shows a method for manufacturing a semiconductor device in the form of a flow chart.

[0021] Figures 2a to 2d schematically show the individual process steps for producing a semiconductor component.

[0022] Figure 3a shows a first spring in a first position, in particular a fastening position.

[0023] Figure 3b shows the first spring in a second position, specifically a separation position. Figure 4 shows two first springs in a first position and opposing coil windings.

[0024] Figure 1 shows, in the form of a flowchart, a method for producing a semiconductor component, in particular with microstructures. In a method step 30, a semiconductor chip is produced with four side surfaces arranged perpendicular to a main extension plane of the semiconductor chip. The produced semiconductor chip furthermore has an outer frame structure that surrounds two adjacent of the four side surfaces of the semiconductor chip. The outer frame structure is in particular L-shaped and thus only partially surrounds the semiconductor chip. The produced semiconductor chip is connected to the outer frame structure by means of at least three first springs. Furthermore, in a method step 40, the semiconductor chip is moved to a next process step by means of a tool, in particular a vacuum gripper, that engages the outer frame structure of the semiconductor chip.In a subsequent method step 70, the outer frame structure and the three first springs are removed from the semiconductor chip.

[0025] Optionally, in a method step 10, the semiconductor chip with the outer frame structure and the at least three first springs is structured out of a wafer, in particular by means of an etching process.

[0026] In an optional method step 20, at least four additional second springs, in particular spiral tubular springs, are structured out of the, in particular circumferential, wafer such that the semiconductor chip with the outer frame structure and the three first springs is connected to the wafer by means of the four second springs in a respective third position, in particular a fastening position, of the second springs. Two of the second springs connect two side surfaces of the semiconductor chip and the two additional second springs connect the two side surfaces of the outer frame structure to the wafer. In a subsequent method step 50, the tool, in particular the vacuum gripper, grips the outer frame structure to move the semiconductor chip to the next process step. The semiconductor chip with the outer frame structure is separated from the wafer in a respective fourth position, in particular a separation position, of the four second springs.

[0027] Optionally, in a method step 60, the outer frame structure and the three springs are separated from the semiconductor chip in a second position, in particular a separation position of the three springs. The three first springs are arranged in the second position in a second recess of the outer frame structure assigned to the respective spring.

[0028] Figure 2a schematically shows, in a section along the main extension plane of the semiconductor chip 99, the produced semiconductor chip 99 with four side surfaces 104a to 104d arranged perpendicular to the main extension plane. The produced semiconductor chip 99 further has an outer frame structure 105 that surrounds two adjacent of the four side surfaces 104a and 104d of the semiconductor chip 99. In this embodiment, the outer frame structure 105 is L-shaped and thus only partially surrounds the semiconductor chip 99. The produced semiconductor chip 99 is connected to the outer frame structure 1055 by means of three first springs 102a to 102c. The three first springs 102a to 102c are designed as spiral tubular springs, in particular as spiral Bourdon tubes.In this embodiment of the semiconductor component, the semiconductor chip 99 is divided into rectangular, adjacent partial areas 103a and 103b. In Figure 2a, in a first position, in particular a fastening position, of the three first springs 102a to 102c, a free end 107a of each of the three first springs 102a to 102c is arranged in a respective first recess 108a of the semiconductor chip 99 assigned to the respective first spring 102a to 102c. The outer frame structure is connected to the semiconductor chip 99 only by means of the three first springs 102a to 102c.

[0029] Furthermore, eight additional second springs 100a to 100h are structured out of the rotating wafer 101 such that the semiconductor chip 99, with the outer frame structure 105 and the three first springs 102a to 102c, is connected to the wafer 101 by means of the eight second springs 100a to 100h in a third position, in particular a fastening position, of the second springs 100a to 100h. In this case, the second springs 100a to 100h are also designed as spiral tubular springs. The wafer 101 is designed as a silicon wafer. Figure 2b shows the eight second springs 100a to 100h in a fourth position, in particular a separation position. In this fourth position, the free ends 98a of the second springs 100a to 100h are arranged in a third recess 99a of the wafer 101 associated with the respective second spring 100a to 100h.Thus, in a method step 110, the semiconductor chip 99 connected to the outer frame structure 105 by means of the three first springs 102a to 102c can be removed from the wafer 101, in particular vertically, and moved to a substrate 109 by means of a tool not shown here for the sake of simplicity.

[0030] Figure 2c shows the semiconductor chip 99 connected to the substrate 109. In this embodiment, the free ends 107a of the three first springs 102a to 102c are arranged in a second position, in particular a separation position, of the three springs. In this second position, the free end 107a is arranged in a second recess 112a of the outer frame structure 105, assigned to the respective first spring 102a to 102c, so that the outer frame structure can be separated from the semiconductor chip 99 in the illustrated method step 111 using the tool (not shown here). In a further method step 115 in Figure 2d, further semiconductor chips 114, identical to the semiconductor chip 99, are arranged and fastened on the substrate 109 directly next to the semiconductor chip 99 using the tool and further outer frame structures 116 for engaging the tool.In this case, a micromirror arrangement 117 is created with a number of independently operable individual mirror elements arranged as an array. These individual mirror elements are each movable via an actuator (not shown here), in particular actuator electrodes, and each have a reflective surface.

[0031] Figure 3a shows, by way of example, a plan view of a spiral tube spring as the first spring 121 in a first position, in particular a fastening position, in which a free end 125 of the first spring 121 is arranged in a first recess 123 of the semiconductor chip 122, which recess is assigned to the first spring 121. The first spring 121 is structured out of the wafer in such a way that a fixed end 124 of the first spring 121 is connected to the outer frame structure 120. The free end 125 of the first spring 121 is structured out of the wafer in such a way that it has a hook-shaped structure at the free end 125, which, in interaction with the assigned first recess 123, serves to connect, in particular couple, to the semiconductor chip 122. For this purpose, the first recess 123 also has a hook-shaped structure at the end 126.The pressure within the first spring 121 is controlled via an air inlet (not shown here) at the fixed end 124 of the first spring 121 in such a way that in the first position of the first spring 121 the ambient air pressure corresponds to the air pressure within the spiral tube spring as the first spring 121.

[0032] Figure 3b, in contrast, shows the first spring in a second position, in particular a separation position, in which the free end 125 is arranged in a second recess 128 of the outer frame structure 120. In this second position of the first spring 121, the outer frame structure 120 is separated from the semiconductor chip 122. The pressure within the first spring 121 is controlled via the air inlet at the fixed end 124 of the first spring 121 such that, in the illustrated second position of the first spring 121, the air pressure within the spiral tube spring as the first spring 121 is lower than the ambient air pressure. The first spring 121 is accordingly moved pneumatically from the first to the second position and vice versa.For this purpose, the semiconductor chip 122 and the surrounding frame 120 are structured out of the wafer in particular such that the air inlet for the first spring 124 is arranged on a first side of the wafer, in particular a top side of the outer frame structure, and the air inlets for the second spring (not shown here) are arranged on a second side of the wafer opposite the first side of the wafer, in particular a bottom side of the wafer. The tool (not shown here), in particular the vacuum gripper, controls the pressure within the first spring 121, in particular when gripping the outer frame structure 120, or generates a negative pressure within the first spring 121 when gripping it.

[0033] Figure 4 shows two first springs 132 and 133 in a first position for connecting the outer frame structure 130 to the semiconductor chip 131. Both first springs 132 and 133 are arranged on the same side surface of the semiconductor chip 131. In the first position, the free ends 138 and 139 of the first springs 132 and 133 are arranged in the first recess 136 and 137 of the semiconductor chip 131 assigned to the respective first spring 132 and 133. In the illustrated embodiment, the first springs 132 and 133 are structured out of the wafer in such a way that the two first springs 132 and 133 have mutually opposite turns of the spirals of the spiral tube springs as first springs 132 and 133. This enables a firm connection of the outer frame 130 to the semiconductor chip 131.

Claims

Claims 1 . A method for producing a semiconductor component, in particular with microstructures, the method comprising the following method steps: - producing (30) a semiconductor chip (99, 114, 122, 131) with four side surfaces (104a, 104b, 104c, 104d) of the semiconductor chip (99, 114, 122, 131) arranged perpendicular to a main extension plane of the semiconductor chip (99, 114, 122, 131), and with an outer frame structure (105, 116, 120, 121) surrounding two adjacent side surfaces (104a, 104b, 104c, 104d) and connected to the semiconductor chip (99, 114, 122, 131) by means of at least three first springs (102a, 102b, 102c, 121, 132, 133), 130), in particular L-shaped outer frame structure, of the semiconductor chip, (99, 114, 122, 131) and - moving (40) the semiconductor chip (99, 114, 122, 131) by means of a tool, in particular a vacuum gripper, acting on the outer frame structure (105, 116, 120, 130) of the semiconductor chip (99, 114, 122, 131) to a next process step, and - removing (70, 111) the outer frame structure (105, 116, 120, 130) and the three first springs (102a, 102b, 102c, 121, 132, 133) from the semiconductor chip (99, 114, 122, 131).

2. Method according to claim 1, characterized in that the at least three first springs (102a, 102b, 102c, 121, 132, 133) are designed as spiral tube springs, in particular as spiral Bourdon tubes.

3. Method according to one of claims 1 or 2, characterized in that the semiconductor chip (99, 114, 122, 131) with the outer frame structure (105, 116, 120, 130) and the at least three first springs (102a, 102b, 102c, 121, 132, 133) is structured out of a wafer (101), in particular by means of an etching process.

4. The method according to claim 3, characterized in that the wafer (101) is formed as a silicon wafer.

5. Method according to one of claims 3 or 4, characterized in that at least four further second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h), in particular spiral tube springs, are structured out of the, in particular circumferential, wafer (101) in such a way that the semiconductor chip (99, 114, 122, 131) with the outer frame structure (105, 116, 120, 130) and the three first springs (102a, 102b, 102c, 121, 132, 133) is connected to the wafer (101) by means of the four second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) in a third position, in particular fastening position, of the second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h).

6. The method according to claim 5, characterized in that two of the second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) connect two side surfaces (104a, 104b, 104c, 104d) of the semiconductor chip (99, 114, 122, 131) and the two further second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) connect the two side surfaces (104a, 104b, 104c, 104d) of the outer frame structure (105, 116, 120, 130) to the wafer (101), wherein subsequently the tool, in particular the Vacuum gripper which engages the outer frame structure (105, 116, 120, 130) to move the semiconductor chip (99, 114, 122, 131) to the next process step, and the semiconductor chip (99, 114, 122, 131) is separated from the wafer (101) with the outer frame structure (105, 116, 120, 130) in a fourth position, in particular a separation position, of the four second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h).

7. The method according to any one of claims 1 to 6, characterized in that the outer frame structure (105, 116, 120, 130) is connected to the semiconductor chip (99, 114, 122, 131) only by means of the at least three first springs (102a, 102b, 102c, 121, 132, 133).

8. The method according to one of claims 1 to 7, characterized in that the at least three first springs (102a, 102b, 102c, 121, 132, 133) are structured out of the wafer (101) in such a way that a fixed end (124) of each of the three first springs (102a, 102b, 102c, 121, 132, 133) is connected to the outer frame structure (105, 116, 120, 130).

9. The method according to one of claims 1 to 8, characterized in that at least in a first position, in particular a fastening position, of the three first springs (102a, 102b, 102c, 121, 132, 133), a free end (107a, 125, 138, 139) of each of the three first springs (102a, 102b, 102c, 121, 132, 133) is arranged in a first recess (108a, 126, 136, 137) of the semiconductor chip (99, 114, 122, 131) assigned to the respective first spring (102a, 102b, 102c, 121, 132, 133).

10. The method according to claim 9, characterized in that the free ends (102a, 102b, 102c, 121, 132, 133) of the three first springs (102a, 102b, 102c, 121, 132, 133) are structured out of the wafer (101) in such a way that they have a structure, in particular a hook-shaped structure, at the free end (107a, 125, 138, 139), which in interaction with the respective associated first recess (108a, 126, 136, 137) serve for connection, in particular coupling, to the semiconductor chip (99, 114, 122, 131). 11 . Method according to one of claims 1 to 10, characterized in that the outer frame structure (105, 116, 120, 130) and the three first springs (102a, 102b, 102c, 121, 132, 133) are separated from the semiconductor chip (99, 114, 122, 131) in a second position, in particular a separation position, of the three first springs (102a, 102b, 102c, 121, 132, 133), wherein the three first springs (102a, 102b, 102c, 121, 132, 133) in the second position in one of the respective first springs (102a, 102b, 102c, 121, 132, 133) assigned second recess (112a, 128) of the outer frame structure (105, 116, 120, 130).

12. Method according to one of claims 1 to 11, characterized in that the pressure within the first (102a, 102b, 102c, 121, 132, 133) and / or second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h), in particular of the spiral tube springs, is controlled via an air inlet at the fixed end (124) of the respective first (102a, 102b, 102c, 121, 132, 133) or second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) such that in the first position of the first springs (102a, 102b, 102c, 121, 132, 133) and / or the third position of the second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) the ambient air pressure corresponds to the air pressure within the spiral tube springs, and in the second position of the first Springs (102a, 102b, 102c, 121, 132, 133) and / or the fourth position of the second spring (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) the air pressure within the spiral tube springs is lower than the ambient air pressure.

13. The method according to claim 12, characterized in that the semiconductor chip (99, 114, 122, 131) and the outer frame structure (105, 116, 120, 130) are structured out of the wafer (101) in such a way that the air inlets for the first springs (102a, 102b, 102c, 121, 132, 133) are arranged on a first side of the wafer (101), in particular a top side of the outer frame structure (105, 116, 120, 130), and the air inlets for the second springs (100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h) are arranged on a second side opposite the first side of the wafer (101). side of the wafer (101), in particular an underside of the wafer (101), and the tool, in particular the vacuum gripper, controls the pressure within the first springs (102a, 102b, 102c, 121, 132, 133) when gripping the outer frame structure (105, 116, 120, 130), in particular generates a negative pressure within the first springs (102a, 102b, 102c, 121, 132, 133).

14. The method according to one of claims 1 to 13, characterized in that the semiconductor chip (99, 114, 122, 131) is moved by means of the tool to a substrate (109) and is subsequently connected to the substrate (109), and after the removal (70, 111) of the produced outer frame structure (105, 116, 120, 130) and the three first springs (102a, 102b, 102c, 121, 132, 133) from the semiconductor chip (99, 114, 122, 131) on the substrate (109), in particular directly next to the semiconductor chip (99, 122, 131), a further, in particular to the semiconductor Chip (99, 114, 122, 131) of the same semiconductor chip (99, 114, 122, 131) is arranged by means of the tool.

15. Micromirror arrangement (117), manufactured by means of a method according to one of claims 1 to 14, with a number of independently operable individual mirror elements which are arranged as a field, in particular an array, and are each movable via an actuator, in particular actuator electrodes, and the individual mirror elements each have a reflection surface.

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