Robust IC packaging

Abstract

The substrate (10) of the integrated circuit package (100) includes a first side (11) and a second side (12) opposite to the first side (11). The substrate (10) also includes a substrate mounting section (20), a tube die mounting section (30) and a recessed section (40). The recessed section (40) includes a recessed portion (41) between the tube die mounting section (30) and the substrate mounting section (20). The substrate (10) also includes an opening (21) extending through the substrate (10) from the first side (11) to the second side (12). At least a portion of the recessed portion (41) intersects with the opening (21).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a continuation of prior U.S. patent application No. 16 / 226,517 filed on December 19, 2018, the entire disclosure of which is incorporated herein by reference. Background Art

[0003] An integrated circuit (IC) is an electrical circuit in which the electronic components of the circuit are fabricated as a single unit, for example, on a substrate of semiconductor material. An IC package is a structure that supports the IC that serves one or more important functions. Typically, the IC package is used to protect the IC from environmental factors (e.g., environmental factors that may cause physical damage or corrosion), regulate the thermal characteristics of the IC (e.g., prevent thermal fatigue), arrange electrical connections of the IC to other electronic devices, and / or increase the mechanical stability of the IC on a designated substrate on which the IC is mounted. Designing an IC package that reliably meets one or more of these purposes is a challenge, especially when the IC will be used in certain demanding environments. Summary of the invention

[0004] Embodiments of the present disclosure generally relate to IC packaging. Certain embodiments can provide robust protection against external stress sources. Such stress sources may include, but are not limited to, thermal fatigue during IC operation, and mechanical stress applied during installation of the IC package and / or caused by thermal expansion / contraction of IC components.

[0005] In particular, one or more embodiments include an IC package that includes a substrate and an electrically insulating die housing. The substrate includes a first side, a second side opposite the first side, a substrate mounting section, and a die mounting section. The substrate also includes a recessed section. The recessed section includes a recess between the die mounting section and the substrate mounting section. The substrate also includes an opening extending through the substrate from the first side to the second side. At least a portion of the recess intersects the opening. The electrically insulating die housing is mounted to the die mounting section.

[0006] One or more other embodiments include an IC package including a substrate. The substrate includes a die mounting section, a substrate mounting section, and a recessed section positioned between the die mounting section and the substrate mounting section. The IC package also includes an opening extending through the substrate at the substrate mounting section and the recessed section. The recessed section is configured to reduce mechanical stress on the die mounting section when torque is applied to a fastener disposed within the opening.

[0007] One or more other embodiments include an IC package including a substrate. The substrate includes a die mounting section, a substrate mounting section, and a recessed section positioned between the die mounting section and the substrate mounting section. The IC package also includes an electrically insulating die housing mounted to the die mounting section. The die housing includes a die cavity and a lead channel spaced apart from the die cavity. The IC package also includes leads that are partially located within the lead channel and extend away from the die cavity. When the leads are soldered to pads on a mounting surface and perform one thousand ambient temperature cycles between -40 degrees Celsius and 85 degrees Celsius, the leads avoid cracking of the die housing due to mechanical stress applied by the leads to the die housing.

[0008] One or more other embodiments include a method of mounting an IC package. The method includes inserting a fastener through an opening extending through the integrated circuit package. The opening is located at a recessed section and a base mounting section of the integrated circuit package. The method also includes mating a head of the inserted fastener to a mating surface of the base mounting section such that the head of the fastener is spaced apart from the recessed section. The method also includes applying a torque to the inserted fastener to secure the base mounting section between the mating head of the fastener and the mounting surface while maintaining the head of the fastener spaced apart from the recessed section.

[0009] Depending on the particular embodiment, any of the above embodiments may also include one or more of the features discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Aspects of the present disclosure are illustrated by way of example and are not limited by the accompanying drawings, in which like reference numerals represent like elements. In general, the use of reference numerals should be considered to refer to the depicted subject matter according to one or more embodiments, while discussions of specific instances of illustrated elements will have letter labels appended thereto (e.g., a discussion of leads 70 in general, rather than a discussion of specific instances of specific leads 70a, 70b).

[0011] Figure 1A and Figure 1B Schematic diagrams of an exemplary IC package viewed from the top and side, respectively, according to one or more embodiments of the present disclosure.

[0012] Figure 2 is a schematic diagram of another exemplary IC package viewed from the top according to one or more embodiments of the present disclosure.

[0013] Figure 3 is a schematic diagram of yet another exemplary IC package mounted to a mounting surface and viewed from the side in accordance with one or more embodiments of the present disclosure.

[0014] Figure 4is a schematic diagram of another exemplary IC package mounted to a mounting surface and viewed from the side in accordance with one or more embodiments of the present disclosure.

[0015] Figure 5 and Figure 6 are isometric schematic diagrams of exemplary six-pin IC packages, each in accordance with one or more embodiments of the present disclosure.

[0016] Figure 7 is a flow chart of an exemplary method according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0017] The embodiments set forth below represent the necessary information to enable those skilled in the art to practice the embodiments, and illustrate the best mode of practicing the embodiments. After reading the following description according to the accompanying drawings, those skilled in the art will understand the concepts of the present disclosure, and will recognize that these concepts are not particularly mentioned in this article. It should be understood that these concepts and applications fall within the scope of the present disclosure and the appended claims.

[0018] It should be understood that although the terms first, second, etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated enumerated items.

[0019] It should be understood that when an element such as a layer, region, or substrate is referred to as being "on another element" or extending "onto another element," it may be directly on another element or extend directly onto another element, or there may be intervening elements. Conversely, when an element is referred to as extending "directly on another element" or "directly on another element," there are no intervening elements. Similarly, it should be understood that when an element such as a layer, region, or substrate is referred to as extending "above another element" or "above another element," it may be directly above another element or extend directly above another element, or there may be intervening elements. Conversely, when an element is referred to as extending "directly above another element" or "directly above another element," there are no intervening elements. It should also be understood that when an element is referred to as being "connected" or "coupled" to another element, the element may be directly connected or coupled to another element, or there may be intervening elements. Conversely, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements.

[0020] Relative terms, such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical", may be used herein to describe the relationship of one element, layer or region to another element, layer or region illustrated in the drawings. It should be understood that these terms and those discussed above are intended to encompass different orientations of the device in addition to the orientation depicted in the drawings.

[0021] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an", and "the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that when used herein, the terms "include", "have", "include", and / or "contain" specify the presence of stated features, integers, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or combinations thereof.

[0022] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It should also be understood that the terms used herein should be interpreted as having the same meaning as they have in the context of this specification and the relevant art, and should not be interpreted as idealized or overly formal meanings unless explicitly defined herein.

[0023] As discussed above, an IC package is a structure used to support an IC that may, for example, protect the IC from environmental factors (e.g., environmental factors that may cause physical damage or corrosion), regulate the thermal characteristics of the IC (e.g., prevent thermal fatigue), arrange electrical connections between the IC and other electronic devices, and / or increase the mechanical stability of the IC on a designated substrate on which the IC is mounted. Figure 1A is a schematic diagram of an IC package 100 according to one or more embodiments of the present disclosure, which may be used for one or more of such purposes and / or other useful purposes.

[0024] IC package 100 includes substrate 10. Figure 1A , the first side 11 of the substrate 10 is visible. The substrate may be made in whole or in part of one or more materials (e.g., alloys, composites, ceramics) having high thermal conductivity (e.g., copper-tungsten (CuW), copper-molybdenum-copper (CMC)). In some specific exemplary embodiments, the substrate is made of CuW 15:85, CuW 10:90, CMC 1:1:1, or CMC 1:3:1.

[0025] The substrate 10 includes a substrate mounting section 20, a die mounting section 30, and a recessed section 40 positioned between the substrate mounting section 20 and the die mounting section 30. The substrate 10 also includes openings 21 at the substrate mounting section 20 and the recessed section 40.

[0026] Figure 1B Shows Figure 1A A side view of the same example IC package 100 shown in FIG. Figure 1B As shown, substrate 10 of IC package 100 includes a first side 11 (e.g., a "top" side), a second side 12 (e.g., a "bottom" side), and a lateral side 13. Second side 12 is opposite first side 11. Lateral side 13 connects first side 11 and second side 12.

[0027] As in Figure 1B As can be seen in FIG. 1 , the recessed section 40 of the IC package 100 includes a recess 41 between the die mounting section 30 and the substrate mounting section 20. Thus, the thickness of the substrate 10 measured between the first side 11 and the second side 12 through the recessed section 40 is less than the thickness of the substrate 10 through the substrate mounting section 20. For example, the thickness of the recessed section 40 can be between 10 and 20 mils less than the thickness of the substrate mounting section 20. In other examples, the difference in thickness can be even greater. In this example, the thickness of the substrate 10 through the recessed section 40 is also less than the thickness of the substrate 10 through the die mounting section 30.

[0028] although Figure 1B The thickness of the substrate through the substrate mounting section 20 is depicted as having the same thickness as the substrate 10 through the die mounting section 30 , but other embodiments of the IC package 100 may include substrate mounting sections 20 and die mounting sections 30 of different thicknesses.

[0029] Substrate 10 also includes an opening 21 extending through substrate 10 from first side 11 to second side 12. Although opening 21 does not extend through lateral side 13 in this example, other examples of IC package 100 may include opening 21 extending through lateral side 13, as will be discussed in further detail below.

[0030] like Figure 1B As shown, at least a portion of the recess 41 intersects the opening 21. In this particular example, the opening 21 extends through the substrate 10 at both the substrate mounting section 20 and the recessed section 40. The opening 21 can be used to mount the IC package 100 to a mounting surface (e.g., a printed circuit board) using a fastener 60 (e.g., a bolt, a screw), such as Figure 2 In some embodiments, a thermal interface material (eg, thermal grease, adhesive, or tape) (not shown) may be used between the substrate 10 and the mounting surface to enhance thermal performance.

[0031] Figure 2 A variation of the exemplary IC package 100 is shown in accordance with certain embodiments so that the first side 11 of the IC package 100 can be seen. In particular, Figure 2 Including the above reference Figure 1A and Figure 1B All elements of the IC package 100 are discussed, as well as fasteners 60 for mounting the IC package 100 to a mounting surface, and other components that support electrical connections between the IC die and other electronic devices that may be on the mounting surface, as will be discussed further below.

[0032] To mount the IC package 100 to the mounting surface, the fastener 60 is inserted through the opening 21 at the base mounting section 20 and the recessed section 40. In addition, the head 61 of the inserted fastener 60 mates with the mating surface 22 of the base mounting section 20. Torque is applied to the inserted fastener 60 (e.g., using a tool inserted into the socket 62 in the head 61 of the fastener 60) to secure the base mounting section 20 between the mating head 61 of the fastener 60 and the mounting surface (this will be shown in further examples below).

[0033] exist Figure 2 In the example of , the IC package 100 also includes an electrically insulating die housing 50 mounted to the die mounting section 30. The die housing 50 includes a die cavity 51. The die cavity 51 can, for example, accept the insertion of an IC die, as will be shown and discussed in more detail below.

[0034] IC package 100 also includes leads 70 extending away from die cavity 51. Figure 3 As shown, the leads are connected to lead pads 72 and are partially located within lead channels 52 of die housing 50. Note that although Figure 2 The exemplary IC package 100 of shows a single lead 70, but other embodiments of the IC package 100 including one or more additional leads 70 will be discussed below. For example, an embodiment including two leads may use one lead to carry a positive supply voltage, and the other lead to carry a negative supply voltage or ground. An embodiment using three leads may use one lead for each of the positive supply voltage, the negative supply voltage, and ground. An embodiment using four leads may, for example, use two leads for each of the positive supply voltage and the negative supply voltage, and use two leads for each of input signal transmission and output signal transmission. Other embodiments may use one or more leads to carry power, signal transmission, reference voltage, and / or ground, etc.

[0035] Figure 3 Shown from the side Figure 2The IC package 100 is mounted to the mounting surface 80 and includes an IC die 90 electrically connected to pads 81 on the mounting surface 80 via leads 70. Figure 3 As can be seen in the illustration of , the head 61 of the inserted fastener 60 cooperates with the mating surface 22 of the base mounting section 20 so that the head 61 of the fastener 60 is above and spaced apart from the recessed section 40 of the base 10 .

[0036] According to an embodiment, torque is applied to the inserted fastener 60 to secure the substrate mounting section 20 between the mating head 61 of the fastener 60 and the mounting surface 80 while keeping the head 61 of the fastener 60 spaced apart from the recessed section 40. Although typical embodiments of the present disclosure may include applying between 40 and 60 inch-ounces of torque to the fastener 60 to mount the IC package 100 to the mounting surface 80, other embodiments may apply even more torque (e.g., up to 80 inch-ounces). In some embodiments, the torque may apply mechanical stress on the die mounting section 30 via the recessed section 40 and the substrate mounting section 20. Thus, in at least some embodiments, the recessed section 40 is configured to reduce the mechanical stress applied to the die mounting section 30 when torque is applied to the fastener 60 disposed within the opening 21. In some such embodiments, the recessed section 40 is configured to reduce mechanical stress on the die mounting section 30 , particularly when torque is applied to the fastener 60 while the mating surface 22 is mated with the head 61 of the fastener 60 .

[0037] Figure 3 Also shown are leads 70 of IC package 100 connected to pads 81 on mounting surface 80 by solder 82. Leads 70 extend away from die cavity 51 and are partially located within lead channels 52 of die housing 50. In some embodiments, leads 70 are configured to avoid cracking of die housing 50 due to mechanical stresses exerted on die housing 50 by leads 70 when leads 70 are soldered to pads 81 on mounting surface 80 and, for example, perform one thousand ambient temperature cycles between -40 degrees Celsius and 85 degrees Celsius. In some embodiments, leads 70 include sides 71 having a thickness of no more than 4 mils, for example, to avoid such cracking.

[0038] Figure 3 The IC package 100 shown in FIG. 1 further includes an IC die 90 partially located within the die cavity 51. The IC die 90 is connected to the lead pads 72 of the leads 70 via bond wires 91. According to one or more other embodiments, the IC die 90 may be completely located within the die cavity 51.

[0039] The die housing 50 may be made of a plastic, resin, polymer, and / or ceramic material that electrically isolates the IC die 90 from unwanted static electricity or other unintended sources of electricity. Figure 4 As shown, IC package 100 may also include a cap 92 mounted to die housing 50. In some embodiments, cap 92 includes a thermally conductive material or shape so that the cap acts as a heat spreader and / or heat sink. Cap 92 may additionally or alternatively be made of a plastic, resin, polymer, and / or ceramic material that electrically insulates IC die 90 from unwanted static electricity or other unintended power sources. In some embodiments, cap 92 and die housing 50 are made of the same material.

[0040] Figure 5 An isometric view of another exemplary IC package 100 is shown. Figure 5 The IC package 100 includes a substrate 10 and an electrically insulating die housing 50. As discussed in the above examples, the die housing 50 is mounted to the die mounting section 30 of the substrate 10. This particular example of the IC package 100 includes two substrate mounting sections 20a, 20b, each of which is separated from the substrate 10 by a corresponding recessed section 40a, 40b. Each recessed section 40a, 40b includes a corresponding recess 41a, 41b between the corresponding substrate mounting section 20a, 20b and the die mounting section 30. The substrate 10 also includes two openings 21a, 21b. Each opening 21a, 21b extends through the substrate 10 from the first side 11 of the substrate 10 to the second side 12 of the substrate 10. Each opening 21a, 21b also extends through the corresponding lateral side 13a, 13b of the substrate 10. Each opening 21a, 21b intersects with a corresponding recess 41a, 41b of the recessed sections 40a, 40b, respectively. like Figure 5 As shown, each of the base mounting sections 20a, 20b includes a corresponding mating surface 22a, 22b for engaging with one or more fasteners ( Figure 5 (not shown) cooperation.

[0041] Figure 5 The die housing 50 shown includes a die cavity 51 and six lead channels 52a-52f. In this example, the IC package 100 also includes six leads 70a-70f, each of which has a corresponding lead pad 70a-70f. Each of the leads 70a-70f is spaced apart from the die cavity 51 and is partially located in a corresponding lead channel 52a-52f. The lead pads 72a-72f of the leads 70a-70f are also each at least partially located in a corresponding lead channel 52a-52f.

[0042] Other embodiments of the IC package 100 may include additional, fewer, or different substrate mounting sections 20. For example, the IC package 100 may include three substrate mounting sections 20, each extending away from the die mounting section 30 in a different direction (e.g., two in opposite directions and one laterally). Other embodiments may additionally or alternatively include multiple substrate mounting sections 20 extending away from the die mounting section 30 in the same direction. Furthermore, some embodiments may include one or more substrate mounting sections 20 connected to the die mounting section 30 without an intervening recessed section 40.

[0043] Embodiments of the present disclosure may additionally or alternatively include one or more leads 70 extending away from the die cavity 51 in any direction. Although the leads 70 of the embodiments discussed above are depicted as straight, other embodiments may include, for example, one or more gull-wing leads, J-shaped leads, butt leads, S-shaped leads, star-shaped J-shaped leads, clip J-shaped leads, and / or through-hole pins. Thus, for example, particular embodiments may be correspondingly adapted for a variety of surface mount or through-hole mount applications.

[0044] Additionally, as discussed above, the IC package 100 may include a cap 92 mounted to the die housing 50 . Figure 6 Another example of an IC package 100 including such a cap 92 is shown.

[0045] like Figure 7 As shown, other embodiments of the present disclosure include a method 200 of mounting an IC package 100. The method 200 includes inserting a fastener 60 through an opening 21 extending through the IC package 100 (block 210). The opening 21 is located at a recessed section 40 and a substrate mounting section 20 of the IC package 100. The method 200 also includes mating a head 61 of the inserted fastener 60 to a mating surface 22 of the substrate mounting section 20 such that the head 61 of the fastener 60 is spaced apart from the recessed section 40 (block 220). The method 200 also includes applying a torque to the inserted fastener 60 to secure the substrate mounting section 20 between the mating head 61 of the fastener 60 and the mounting surface 80 while maintaining the head 61 of the fastener 60 spaced apart from the recessed section 40 (block 230).

[0046] Embodiments of the present disclosure may additionally or alternatively include any compatible combination of features described in the above or following claims. Of course, without departing from the basic features of the present invention, the embodiments may be implemented in a manner different from that specifically set forth herein. The present embodiments are to be considered in all respects to be illustrative and not restrictive, and all changes within the meaning and equivalent range of the appended claims are intended to be included therein.

Claims

1. An integrated circuit package (100), comprising: A substrate (10) comprising: a first side (11) and a second side (12) opposite to the first side (11); a substrate mounting section (20) and a die mounting section (30); a recessed section (40) comprising a recessed portion (41) between the die mounting section (30) and the substrate mounting section (20); an opening (21) extending from the first side (11) through the base (10) to the second side (12), wherein at least a portion of the recess (41) intersects the opening (21); an electrically insulating die housing (50) mounted to the die mounting section (30), The base mounting section (20) includes a mating surface (22) configured to mate with a head (61) of the fastener (60) when the fastener (60) is disposed within the opening (21), the head (61) being spaced above the recessed section (40).

2. The integrated circuit package according to claim 1, wherein: The substrate (10) has a thickness measured between the first side (11) and the second side (12), the thickness of the substrate (10) through the recessed section (40) being less than the thickness of the substrate (10) through the substrate mounting section (20).

3. The integrated circuit package according to claim 2, wherein: The thickness of the substrate (10) passing through the recessed section (40) is also smaller than the thickness of the substrate (10) passing through the die mounting section (30).

4. The integrated circuit package of claim 1, wherein: The substrate (10) further comprises a lateral side (13) connecting the first side (11) and the second side (12), and the opening (21) further extends through the lateral side (13).

5. The integrated circuit package of claim 1, wherein: The recessed section (40) is configured to reduce mechanical stress on the die mounting section (30) when torque is applied to the fastener (60) while the mating surface (22) and the head (61) of the fastener (60) are mated.

6. The integrated circuit package of claim 1, wherein: The tube core housing (50) comprises a tube core cavity (51) and a lead channel (52) spaced apart from the tube core cavity (51); The integrated circuit package (100) also includes a lead (70) partially located within the lead channel (52) and extending away from the die cavity (51), the lead (70) including a side (71) having a thickness of no more than four mils.

7. The integrated circuit package of claim 6, wherein: When the leads (70) are soldered to pads (81) on a mounting surface (80) and subjected to one thousand ambient temperature cycles between -40 degrees Celsius and 85 degrees Celsius, the leads (70) avoid cracking of the die housing (50) due to mechanical stress applied by the leads (70) to the die housing (50).

8. The integrated circuit package of claim 1, further comprising an integrated circuit die (90), wherein: The die housing (50) includes a die cavity (51), and the integrated circuit die (90) is at least partially located within the die cavity (51).

9. An integrated circuit package (100), comprising: A substrate (10) comprising a die mounting section (30), a substrate mounting section (20), and a recessed section (40) positioned between the die mounting section (30) and the substrate mounting section (20); an opening (21) extending through the base (10) at the base mounting section (20) and the recessed section (40); The recessed section (40) is configured to reduce mechanical stress on the die mounting section (30) when torque is applied to a fastener (60) disposed within the opening (21).

10. The integrated circuit package of claim 9, wherein: The substrate (10) further comprises a first side (11) and a second side (12) opposite to the first side (11); The substrate (10) has a thickness measured between the first side (11) and the second side (12); The thickness of the base (10) passing through the recessed section (40) is smaller than the thickness of the base (10) passing through the base mounting section (30).

11. The integrated circuit package of claim 10, wherein: The thickness of the substrate (10) passing through the recessed section (40) is also smaller than the thickness of the substrate (10) passing through the die mounting section (30).

12. The integrated circuit package of claim 9, wherein: The substrate (10) further comprises a first side (11), a second side (12) opposite to the first side (11), and a lateral side (13) connecting the first side (11) and the second side (12); To extend through the substrate (10) at the substrate mounting section (20) and the recessed section (40), the opening (21) extends from the first side (11) through the substrate (10) to the second side (12) and through the lateral side (13).

13. The integrated circuit package of claim 9, wherein: The base mounting section (20) includes a mating surface (22) configured to mate with a head (61) of the fastener (60) when the fastener (60) is disposed within the opening (21), the head (61) being spaced above the recessed section (40); In order to reduce the mechanical stress applied to the die mounting section (30) when torque is applied to the fastener (60), the recessed section (40) is configured to reduce the mechanical stress when torque is applied to the fastener (60) while the mating surface (22) and the head (61) of the fastener (60) are mated.

14. The integrated circuit package of claim 9, further comprising: An electrically insulating die housing (50) mounted to the die mounting section (30), the die housing (50) comprising a die cavity (51) and a lead channel (52) spaced apart from the die cavity (51); A lead (70) is partially located within the lead channel (52) and extends away from the die cavity (51), the lead (70) including a side (71) having a thickness of no more than four mils.

15. The integrated circuit package of claim 14, wherein: When the leads (70) are soldered to pads (81) on a mounting surface (80) and subjected to one thousand ambient temperature cycles between -40 degrees Celsius and 85 degrees Celsius, the leads (70) avoid cracking of the die housing (50) due to mechanical stress applied by the leads (70) to the die housing (50).

16. The integrated circuit package of claim 14, further comprising an integrated circuit die (90) at least partially located within the die cavity (51).

17. An integrated circuit package (100), comprising: A substrate (10) comprising a die mounting section (30), a substrate mounting section (20), and a recessed section (40) positioned between the die mounting section (30) and the substrate mounting section (20); An electrically insulating die housing (50) mounted to the die mounting section (30), the die housing (50) comprising a die cavity (51) and a lead channel (52) spaced apart from the die cavity (51); Leads (70) partially located within the lead channel (52) and extending away from the die cavity (51), wherein when the leads (70) are soldered to pads (81) on a mounting surface (80) and subjected to one thousand ambient temperature cycles between -40 degrees Celsius and 85 degrees Celsius, the leads (70) avoid cracking of the die housing (50) due to mechanical stresses exerted on the die housing (50) by the leads (70), The recessed section (40) is configured to reduce mechanical stress on the die mounting section (30) when torque is applied to a fastener (60) disposed within the opening (21).

18. The integrated circuit package of claim 17, wherein: The lead (70) includes sides (71) having a thickness of no more than four mils.

19. A method (200) of mounting an integrated circuit package (100), the method comprising: inserting (210) a fastener (60) through an opening (21) extending through the integrated circuit package (100), wherein the opening (21) is located at a recessed section (40) and a substrate mounting section (20) of the integrated circuit package (100); engaging (220) the head (61) of the inserted fastener (60) with the mating surface (22) of the base mounting section (20) such that the head (61) of the fastener (60) is spaced apart from the recessed section (40); Torque is applied (230) to the inserted fastener (60) to secure the base mounting section (20) between the head (61) of the fastener (60) and a mounting surface (80) while maintaining the head (61) of the fastener (60) spaced apart from the recessed section (40).

Images