Improved life of high-power tungsten halogen lamps with J-hook design

Abstract

A lamp and epitaxial processing apparatus are described herein. In one embodiment, the lamp includes a bulb, a filament, and a plurality of filament supports spaced apart from the filament, each of the plurality of filament supports having a hook support and a hook. The hook includes a connector configured to secure the hook to the hook support, a first vertical portion extending from the connector toward the filament, and a rounded portion extending from an end of the first vertical portion distal from the connector and configured to wrap around the filament. A second vertical portion extends from an end of the rounded portion distal from the first vertical portion, the second vertical portion having a length between 60% and 100% of the length of the first vertical portion.

Description

[Technical field]

[0001]

[0001] Embodiments of the present disclosure relate generally to thermal processing of thin films on substrates such as silicon wafers, and more particularly to an apparatus used to support a filament in a lamp used to generate radiation for such thermal processing. [Background technology]

[0002]

[0002] In solid-state integrated circuit manufacturing, epitaxial processing is typically performed in an epitaxial processing chamber. A substrate, placed on a susceptor in the epitaxial processing equipment, is typically heated by lamps located above and / or below the substrate. The susceptor is typically heated by lamps located below the susceptor. Upper and lower domes, which may be quartz, surround the processing chamber. A lift arm and a susceptor arm move apart from each other, thereby separating the substrate from the susceptor, and positioning the processed substrate to be removed from the processing chamber by a robot and replaced with the substrate to be processed in the processing chamber.

[0003]

[0003] The lamps maintain the temperature of the substrate and the susceptor. If a lamp burns out, the process chamber is taken out of production and one or more of the lamps are replaced. These lamp failures are costly to manufacturers due to the downtime required to replace the failed lamp. To avoid premature lamp failure, lamps that can withstand the shipping / delivery process without developing defects are preferred. For example, premature failure can occur when a lamp filament becomes detached from one or more filament supports.

[0004]

[0004] Figure 2 shows a conventional lamp 200 that may be used for epitaxial processing in a processing chamber as described above. The lamp 200 includes a bulb 112, a filament 120, a plurality of filament supports 103, a ground wire 125, a first glass support 130, and a second glass support 132. The filament 120 is typically fabricated from annealed tungsten or other suitable material. The filament 120 is generally configured as a coil spring or the like having a plurality of individual coils 107. The first glass support 130 and the second glass support 132 are configured to support the filament 120, the filament support 103, and the ground wire 125 within the lamp 200. The plurality of filament supports 103 are configured to be positioned within the bulb 112 in spaced relation to the filament 120. The filament 120 further includes a first filament lead 122 and a second filament lead 124. A first filament lead 122 is configured to enter the light bulb 112 from a source of electrical potential (not shown) as a cathode for the filament 120, while a second filament lead 124 is configured to contact a ground wire 125 as an anode for the filament 120. The ground wire 125 is configured to exit the light bulb 112 and connect to an electrical ground (not shown).

[0005] In a typical operation of a lamp 200 used in epitaxial processing, a current is applied to the filament 120, which emits light and heat. In some embodiments, the filament 120 is made of tungsten or other suitable conductor. Tungsten filaments emit infrared radiation at temperatures up to about 3400 degrees Celsius. It will be understood that other metals may be utilized without departing from the scope of the present disclosure. The light bulb 112 is filled with a halogen gas. Other gases may be used in the light bulb 112. When a potential is applied between the first filament lead 122 and the second filament lead 124 from a potential source, the tungsten in the filament 120 is excited and vaporizes. The vaporized tungsten reacts with and combines with the halogen gas to produce tungsten-halogen molecules. The tungsten-halogen molecules then travel toward the light bulb 112. As the tungsten-halogen molecules move away from the filament, their temperature drops and the bulb 112 pushes the tungsten-halogen molecules back towards the filament 120, breaking the bond between the tungsten and the halogen. The evaporated tungsten is then redeposited on the filament 120. However, when evaporated tungsten is redeposited on the filament 120, it is not necessarily redeposited in the same area of ​​the filament 120 from which it evaporated. When a halogen lamp is repeatedly turned on, as tungsten is redeposited on the bottom of the filament 120, the filament 120 begins to sag, eventually causing the individual coils 107 to touch each other and short out, or the filament 120 to break, leading to failure of the lamp 200.

[0006]

[0006] Referring to FIG. 3, the filament supports 103 are shown. Each of the filament supports 103 further includes a hook support 140 and a hook 150. The hook 150 further includes a connector 152, a first vertical portion 154, a rounded portion 156, and a second vertical portion 158. The connector 152 is configured to couple the hook 150 to the hook support 140. The connector 152 is typically a wire that is wrapped around the hook support 140 one or more times to secure the hook 150 to the hook support 140. The connector 152 may be welded or otherwise secured to further secure the hook 150 to the hook support 140. The first vertical portion 154 of the hook 150 is configured to extend from the connector 152 of the hook 150 toward the filament 120. A rounded portion 156 of the hook 150 extends from an end of the first vertical portion 154 distal to the connector 152. The rounded portion 156 is further configured to wrap around the filament 120 to support the filament within the light bulb 112. A second vertical portion 158 is configured to extend from an end of the rounded portion 156 distal from the first vertical portion 154.

[0007]

[0007] Typically, the prior art lamp 200 includes a hook 150 that is a J-hook. The length L2 of the second vertical portion 158 is, in one embodiment, less than 60% of the length L1 of the first vertical portion 154. In particular, the second vertical portion 158 is between 45% and 55% of the length of the first vertical portion 154. In one embodiment, the length L1 of the first vertical portion 154 is between 0.24 inches and 0.26 inches. Meanwhile, the length L2 of the second vertical portion 158 is between 0.123 inches and 0.127 inches. The length-to-length ratio of the prior art J-hooks allowed for premature failure of parts due to the rigors of shipping / transportation, and also contributed to failures within the epitaxial processing equipment 100. Thus, any vibration or agitation experienced by the lamp 200 may cause the filament 120 to become dislodged from the hook 150. Furthermore, the lack of structural support for lamp 200 exacerbates the effects of sagging due to redeposition of evaporated tungsten, leading to premature lamp failure.

[0008]

[0008] Therefore, what is needed in the art is a filament support that adequately supports the filament without degrading the performance of the lamp in the desired application. Summary of the Invention

[0009]

[0009] Embodiments of the present disclosure relate generally to thermal processing of thin films on substrates such as silicon wafers. In particular, embodiments of the present disclosure relate to improved lamps and epitaxial processing equipment having the improved lamps.

[0010]

[0010] In one embodiment, a lamp is disclosed. The lamp includes a bulb, a filament, and a plurality of filament supports spaced apart from the filament. The plurality of filament supports includes at least a first filament support and a second filament support. Each of the filament supports further includes a hook support and a hook. The hook includes a connector, a first vertical portion, a rounded portion, and a second vertical portion. The connector is configured to secure the hook to the hook support. The first vertical portion extends from the connector toward the filament. The rounded portion extends from an end of the first vertical portion distal from the connector and is configured to wrap around the filament. The second vertical portion extends from an end of the rounded portion distal from the first vertical portion. The second vertical portion of the first filament support has a length between 60% and 100% of a length of the first vertical portion of the first filament support. The first vertical portion of the first filament support is longer than the first vertical portion of the second filament support.

[0011]

[0011] In another embodiment, an epitaxial processing apparatus is disclosed. The apparatus includes a processing chamber, a susceptor in the processing chamber, and a plurality of lamps. The susceptor is configured to support a substrate. The processing chamber is defined by an upper dome and a lower dome. The plurality of lamps are disposed above the upper dome and below the lower dome. The lamp includes a bulb, a filament, and a plurality of filament supports spaced apart from the filament. The plurality of filament supports include at least a first filament support and a second filament support. Each of the filament supports further includes a hook support and a hook. The hook includes a connector, a first vertical portion, a rounded portion, and a second vertical portion. The connector is configured to secure the hook to the hook support. The first vertical portion extends from the connector toward the filament. The rounded portion extends from an end of the first vertical portion distal from the connector and is configured to wrap around the filament. The second vertical portion extends from an end of the rounded portion distal from the first vertical portion. The second vertical portion of the first filament support has a length between 60% and 100% of the length of the first vertical portion of the first filament support. The first vertical portion of the first filament support is longer than the first vertical portion of the second filament support.

[0012]

[0012] In order that the features of the present disclosure described above may be understood in detail, a more particular description of the present disclosure briefly summarized above may be obtained by reference to a number of embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the attached drawings only show exemplary embodiments, and therefore should not be considered as limiting the scope of the present disclosure, and other equally effective embodiments may be acceptable. [Brief description of the drawings]

[0013] [Figure 1]

[0013] A cross section of an epitaxial system is shown. [Diagram 2]

[0014] 1 shows a conventional lamp for epitaxial processing. [Diagram 3]

[0015] 1 shows a conventional filament support for supporting a filament. [Figure 4]

[0016] 1 illustrates a lamp for epitaxial processing according to one embodiment of the present disclosure. [Diagram 5]

[0017] 1 illustrates a filament support for supporting a filament according to one embodiment of the present disclosure. [Figure 6]

[0018] 1 illustrates a light intensity map according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014]

[0019] To facilitate understanding, wherever possible, the same reference numerals have been used to designate identical elements common to the figures. It is believed that elements and features of one embodiment may be beneficially incorporated in other embodiments without additional recitation.

[0015]

[0020] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to the thermal processing of thin films on substrates. In particular, embodiments of the present disclosure relate to an apparatus used to support a filament in a lamp used to generate radiation for such thermal processing.

[0016]

[0021] FIG. 1 shows an epitaxial processing apparatus 100 that can be used for epitaxial processing. The epitaxial processing apparatus 100 includes improved lamps 106. A substrate 102 disposed within the processing apparatus 100 is heated by lamps 106 typically disposed above and / or below the substrate 102. A susceptor 104 is heated by lamps 106 typically disposed below the susceptor 104. An upper dome 108 and a lower dome 109, which may be quartz, surround a processing chamber 113. The lift arm 101 and the susceptor arm 105 move apart from each other, thereby separating the substrate 102 from the susceptor 104, and positioning the processed substrate 102 to be removed from the processing chamber 113 by a robot (not shown) and replaced with an unprocessed substrate 102.

[0017]

[0022] The lamp 106 is configured to provide suitable support for the filament 120. Referring to FIG. 4, further details of the lamp 106 for epitaxial processing are shown. The lamp 106 includes a bulb 112, a filament 120, a number of filament supports 403, a ground wire 125, a first glass support 130, and a second glass support 132. According to some embodiments, the filament 120 is constructed of annealed tungsten or other suitable material. In some embodiments, the filament 120 is configured as a coil spring having a number of individual coils 107. The first glass support 130 and the second glass support 132 are configured to support the filament 120, the filament support 403, and the ground wire 125 within the lamp 106. The first glass support 130 and the second glass support 132 are spaced apart within the bulb 112. The filament 120 is disposed within the light bulb 112 and extends between a first glass support 130 and a second glass support 132. A plurality of filament supports 403 are configured to be spaced apart relative to the filament 120 and disposed within the light bulb 112. In one embodiment, the lamp 106 includes three filament supports 403 spaced apart along the filament 120 for maximum support. The filament 120 further includes a first filament lead 122 and a second filament lead 124. The first filament lead 122 is configured to enter the light bulb 112 from a source of electrical potential as a cathode for the filament 120, while the second filament lead 124 is configured to contact a ground wire 125 as an anode for the filament 120. The ground wire 125 is configured to exit the light bulb 112 and connect to an electrical ground.

[0018]

[0023] Referring to FIG. 5, a plurality of filament supports 403 are shown. The plurality of filament supports 403 includes at least a first filament support 403A and a second filament support 403B. Each of the filament supports 403 further includes a hook support 440 and a hook 450. The first filament support 403A includes a first hook support 440A and a first hook 450A, and the second filament support 403B includes a second hook support 440B and a second hook 450B. The first hook support 440A of the first filament support 403A is coupled to the first glass support 130 and the second glass support 132. The second hook support 440B of the second filament support 403B is coupled to the second glass support 132. The first hook 450A is coupled to the first hook support 440A. The first hook 450A further includes a connector 452A, a first vertical portion 454A, a rounded portion 456A, and a second vertical portion 458A. The first vertical portion 454A extends from the first hook support 440A toward the filament 120. The rounded portion 456A extends from an end of the first vertical portion 454A distal from the first hook support 440A and is configured to wrap around the filament 120. The second vertical portion 458A extends from an end of the rounded portion 456A distal from the first vertical portion 454A to an end 459 at a height beyond the edge 442 of the second hook support 440B closest to the filament 120, as indicated by line 460. The second hook 450B is coupled to the second hook support 440B. The second hook 450B further includes a connector 452B, a first vertical portion 454B, a rounded portion 456B, and a second vertical portion 458B. The first vertical portion 454B extends from the second hook support 440B toward the filament 120. The rounded portion 456B extends from an end of the first vertical portion 454B distal from the second hook support 440B. The rounded portion 456B is configured to wrap around the filament 120. The second vertical portion 458B extends from an end of the rounded portion 456B distal from the first vertical portion 454B.Generally, the connector 452 is configured to couple the hook 450 to the hook support 440. In one embodiment, the connector 452 is configured with a wire that is wrapped one or more times around the hook support 440 to secure the hook 450 to the hook support 440. In one embodiment, the connector 452 may be welded to further secure the hook 450 to the hook support 440. A first vertical portion 454 of the hook 450 is configured to extend from the connector 452 of the hook 450 towards the filament 120.

[0019]

[0024] In one embodiment, the third filament support 403C includes a third hook support 440C and a third hook 450C. The third hook support 440C is coupled to the first glass support 130. The third hook 450C further includes a connector 452C, a first vertical portion 454C, a rounded portion 456C, and a second vertical portion 458C. The first vertical portion 454C extends from the third hook support 440C toward the filament 120. The rounded portion 456C extends from an end of the first vertical portion 454C distal from the third hook support 440C and is configured to wrap around the filament 120. The second vertical portion 458C extends from an end of the rounded portion 456C distal from the first vertical portion 454C. The second vertical portion 458A of the first hook 450A extends from an end of the rounded portion 456A distal from the first vertical portion 454A to an end 459 at a height that exceeds the edge of the third hook 450C closest to the filament 120 (not shown).

[0020]

[0025] A rounded portion 456 of the hook 450 extends from a first end of the first vertical portion 454 distal to the connector 452. The rounded portion 456 is further configured to wrap around the filament 120 to support the filament 120 within the light bulb 112. In one embodiment, the rounded portion 456 of the hook 450 is configured to be semicircular or partially semicircular. In one embodiment, the semicircular radius R2 of the rounded portion 456 is 0.5 inches. The rounded portion 456 is further configured to contact less than 50% of the circumference of the filament 120, such as less than 45% of the circumference of the filament 120, such as less than 35% of the circumference of the filament 120, such as less than 25% of the circumference of the filament 120. By contacting less than 50% of the circumference of the filament 120, the rounded portion 456 can limit the impact of the filament support 403 on the performance of the lamp 106, as will be described below. The second vertical portion 458 is configured to extend from a first end of the rounded portion 456 distal from the first end of the first vertical portion 454. In one embodiment, the second vertical portion extends away from the filament 120 parallel to the first vertical portion 454.

[0021]

[0026] In one embodiment, the lamp 106 includes a hook 450 that is a J-hook. The second vertical portion 458A is configured to have a length L4 that is between 60% and 100% of the length L3 of the first vertical portion 454A. In another embodiment, the second vertical portion 458A has a length L4 that is between 65% and 85% of the length L3 of the first vertical portion 454A. In one embodiment, the second vertical portion 458A has a length L4 that is between 70% and 80% of the length L3 of the first vertical portion 454A. In one embodiment, the second vertical portion 458A has a length L4 that is between 74 percent and 77 percent of the length L3 of the first vertical portion 454A. In one embodiment, the length L3 of the first vertical portion 454A is between 0.2 inches and 0.3 inches, such as between 0.24 inches and 0.26 inches. In one embodiment, the length L4 of the second vertical portion 458A is between 0.15 inches and 0.25 inches, such as between 0.178 inches and 0.202 inches.

[0022]

[0027] By making the length L4 of the second vertical portion 458 greater than 60% of the length L3 of the first vertical portion 454, the likelihood of the filament 120 becoming dislodged from the hook 450 is significantly reduced, thus reducing premature failure due to malfunction during shipping / transport and within the epitaxial processing apparatus 100. Significant vibration or agitation would be required to dislodge the filament 120 from the hook 450. Thus, during use, the structural support keeps the individual coils 107 from contacting each other, limiting the effects of sagging caused by redeposition of evaporated tungsten and reducing premature failure.

[0023]

[0028] In one embodiment of the lamp 106, the first vertical portion 454A of the first filament support 403A is longer than the first vertical portion 454B of the second filament support 403B. The first filament support 403A is further configured to be spaced further from the filament 120 than the second filament support 403B. In another embodiment, the lamp 106 is configured to include a third filament support 403C. The first filament support 403A is configured to be between the second filament support 403B and the third filament support 403C. Furthermore, the first vertical portion 454A of the first filament support 403A is longer than the first vertical portion 454B of the second filament support 403B and the first vertical portion (not shown) of the third filament support 403C. The first filament support 403A is spaced further from the filament 120 than the second filament support 403B and the third filament support 403C.

[0024]

[0029] Referring to FIG. 6, the lamp 106 was configured to rotate around the sensor 610 to generate plot 615. Plot 615 shows the light intensity of the lamp 106 during the rotation of the lamp 106. At the 0° mark, the sensor 610 is positioned such that the area 620 faces the sensor 610. When the sensor 610 faces the area 620, no light is measured or a negligible amount of light is measured. When the lamp 106 rotates towards the 90° mark, the area 630 faces the lamp 106. The light intensity is significantly higher at the 90° mark because the filament 120 faces the sensor 610 directly. The plot 615 continues to area 640 at the 180° mark and area 650 at the 270° mark. When the lamp 106 rotates from area 630 to area 640, the filament 120 is no longer facing directly towards the sensor 610 and the light intensity decreases. Approaching region 650, the light intensity increases due to the filament 120 facing directly towards the sensor 610. In region 650, the light intensity is greater than in region 630. This is due in part to the fact that in region 630, there are multiple filament supports 403. The filament supports 403 block a portion of the light emitted from the lamp 106. However, in region 650, there is only a ground wire 125, so less light is blocked. By extending parallel away from the rounded portion 456 of the hook 450, the first vertical portion 454 and the second vertical portion 458 further limit the amount of light blocked by the hook 450, allowing for more efficient heating of the susceptor 104 and substrate 102. Similarly, by limiting the amount of contact between the rounded portion 456 and the filament 120, the amount of light blocked by the hook 450 is reduced, again allowing for more efficient heating of the susceptor 104 and substrate 102.

[0025]

[0030] In addition to reducing the amount of light blocked by the hook 450 by limiting the amount of contact between the rounded portion 456 and the filament 120, the limited amount of contact between the rounded portion 456 and the filament 120 can extend the life of the lamp 106. The filament 120 will rise to a high temperature (i.e., between 600° C. and 1200° C.) when a potential is applied across it. However, the hook 450 will not rise to a high temperature because there is no potential applied to the hook 450. Thus, cold spots tend to develop at the interface between the rounded portion 456 of the hook 450 and the filament 120. The development of cold spots affects the halogen-tungsten bonding process, making the redeposition process more uneven and increasing filament sagging, which can result in premature failure. By limiting the amount of contact between the rounded portion 456 of the hook 450 and the filament 120, the number of cold spots is reduced, leading to a more efficient halogen-tungsten bonding process and a more uniform redeposition process.

[0026]

[0031] In summary, described herein is a lamp including a bulb, a filament, and a plurality of filament supports spaced apart relative to the filament, each of the filament supports further comprising a hook support and a hook, the hook including a connector configured to secure the hook to the hook support, a first vertical portion extending from the connector toward the filament, a rounded portion extending from an end of the first vertical portion distal from the connector and configured to wrap around the filament, and a second vertical portion extending from an end of the rounded portion distal from the first vertical portion and having a length between 60% and 100% of the length of the first vertical portion. The lamps provide sufficient support to prevent defects from forming during shipping / transportation, thus reducing premature failure, while having minimal impact on the ability of the lamps to efficiently heat the substrate and susceptor.

[0027]

[0032] While the forgoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, which is defined by the following claims.

Claims

1. A lamp, light bulb, a first glass support and a second glass support disposed in a spaced relationship within the lamp; a filament disposed within the lamp and extending between the first glass support and the second glass support; a first hook support coupled to the first glass support and the second glass support; a second hook support coupled to the second glass support; a first hook coupled to the first hook support, a first vertical portion extending from the first hook support toward the filament; a rounded portion extending from an end of the first vertical portion distal to the first hook support and configured to wrap around the filament; and a first hook including a second vertical portion extending from an end of the rounded portion distal from the first vertical portion to a height beyond an edge of the second hook support closest to the filament; and a second hook coupled to the second hook support, a first vertical portion extending from the second hook support toward the filament; a rounded portion extending from an end of the first vertical portion distal to the second hook support and configured to wrap around the filament; and The lamp further comprises a second hook having a second vertical portion extending from an end of the rounded portion distal from the first vertical portion.

2. a third hook support coupled to the first glass support, the second vertical portion of the first hook extending from an end of the rounded portion of the first hook distal from the first vertical portion of the first hook to a height beyond an edge of the third hook support closest to the filament; and a third hook coupled to the third hook support, a first vertical portion extending from the third hook support toward the filament; a rounded portion extending from an end of the first vertical portion distal to the third hook support and configured to wrap around the filament; and 10. The lamp of claim 1, further comprising a third hook comprising a second vertical portion extending from an end of the rounded portion distal from the first vertical portion.

3. 3. The lamp of claim 2, wherein the second hook support and the third hook support are cantilevered from the second glass support and the first glass support, respectively.

4. 3. The lamp of claim 2, wherein the first hook support is supported by the first glass support and the second glass support.

5. 3. The lamp of claim 2, wherein the first hook support is spaced further from the filament than one of the second hook support and the third hook support.

6. 3. The lamp of claim 2, wherein the second vertical portion of the first hook is longer than one of the second vertical portion of the second hook and the second vertical portion of the third hook.

7. 3. The lamp of claim 2, wherein the first vertical portion of the first hook is longer than one of the first vertical portion of the second hook and the first vertical portion of the third hook.

8. 2. The lamp of claim 1, wherein the second vertical portion of the first hook has a length between 60% and 100% of a length of the first vertical portion of the first hook.

9. A lamp, light bulb, Filaments, and a plurality of filament supports spaced apart from the filament, the plurality of filament supports comprising at least a first filament support and a second filament support, each of the plurality of filament supports further comprising a hook support and a hook, the hook comprising: a connector configured to secure the hook to the hook support; a first vertical portion extending from the connector toward the filament; a rounded portion extending from an end of the first vertical portion distal to the connector and configured to wrap around the filament; and a second vertical portion extending from an end of the rounded portion distal from the first vertical portion and having a length between 60% and 100% of the length of the first vertical portion; The first vertical portion of the first filament support is longer than the first vertical portion of the second filament support.

10. 10. The lamp of claim 9, wherein the second vertical portion has a length that is between 70% and 80% of the length of the first vertical portion.

11. 11. The lamp of claim 10, wherein the second vertical portion has a length between 74% and 77% of the length of the first vertical portion.

12. 10. The lamp of claim 9, wherein the length of the first vertical portion is between 0.2 and 0.3 inches.

13. 13. The lamp of claim 12, wherein the length of the first vertical portion is between 0.24 inches and 0.26 inches.

14. 10. The lamp of claim 9, wherein the length of the second vertical portion is between 0.05 and 0.7 inches.

15. 15. The lamp of claim 14, wherein the length of the second vertical portion is between 0.178 inches and 0.202 inches.

16. 10. The lamp of claim 9, wherein the hooks contact less than 50% of the circumference of the filament.

17. 10. The lamp of claim 9 further comprising a third filament support, said first filament support being between said second filament support and said third filament support.

18. 20. The lamp of claim 17, wherein the first vertical portion of the first filament support is longer than the first vertical portion of the second filament support and the first vertical portion of the third filament support.

19. 20. The lamp of claim 18, wherein the first filament support is spaced further from the filament than the second filament support and the third filament support.

20. 1. An epitaxial processing apparatus comprising: a processing chamber defined by an upper dome and a lower dome; a susceptor in the processing chamber configured to support a substrate; a plurality of lamps disposed above the upper dome and below the lower dome, the plurality of lamps comprising: light bulb, Filaments, and a plurality of filament supports spaced apart from the filament, the plurality of filament supports comprising at least a first filament support and a second filament support, each of the plurality of filament supports further comprising a hook support and a hook, the hook comprising: a connector configured to secure the hook to the hook support; a first vertical portion extending from the connector toward the filament; a rounded portion extending from an end of the first vertical portion distal to the connector and configured to wrap around the filament; and a second vertical portion extending from an end of the rounded portion distal from the first vertical portion and having a length between 60% and 100% of the length of the first vertical portion; The first vertical portion of the first filament support is longer than the first vertical portion of the second filament support.

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