US20220181272A1 - Stem for semiconductor package - Google Patents
Stem for semiconductor package Download PDFInfo
- Publication number
- US20220181272A1 US20220181272A1 US17/153,004 US202117153004A US2022181272A1 US 20220181272 A1 US20220181272 A1 US 20220181272A1 US 202117153004 A US202117153004 A US 202117153004A US 2022181272 A1 US2022181272 A1 US 2022181272A1
- Authority
- US
- United States
- Prior art keywords
- frame
- plate
- stem
- semiconductor package
- hole
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49811—Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
- H01L23/04—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls
- H01L23/043—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having a conductive base as a mounting as well as a lead for the semiconductor body
- H01L23/045—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having a conductive base as a mounting as well as a lead for the semiconductor body the other leads having an insulating passage through the base
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
- H01L23/04—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls
- H01L23/043—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having a conductive base as a mounting as well as a lead for the semiconductor body
- H01L23/049—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having a conductive base as a mounting as well as a lead for the semiconductor body the other leads being perpendicular to the base
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
- H01L23/04—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls
- H01L23/053—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having an insulating or insulated base as a mounting for the semiconductor body
- H01L23/055—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having an insulating or insulated base as a mounting for the semiconductor body the leads having a passage through the base
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
- H01L23/10—Containers; Seals characterised by the material or arrangement of seals between parts, e.g. between cap and base of the container or between leads and walls of the container
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/12—Mountings, e.g. non-detachable insulating substrates
- H01L23/13—Mountings, e.g. non-detachable insulating substrates characterised by the shape
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/495—Lead-frames or other flat leads
- H01L23/49503—Lead-frames or other flat leads characterised by the die pad
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/495—Lead-frames or other flat leads
- H01L23/49541—Geometry of the lead-frame
- H01L23/49558—Insulating layers on lead frames, e.g. bridging members
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/495—Lead-frames or other flat leads
- H01L23/49568—Lead-frames or other flat leads specifically adapted to facilitate heat dissipation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49827—Via connections through the substrates, e.g. pins going through the substrate, coaxial cables
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/562—Protection against mechanical damage
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
- H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L24/42—Wire connectors; Manufacturing methods related thereto
- H01L24/47—Structure, shape, material or disposition of the wire connectors after the connecting process
- H01L24/49—Structure, shape, material or disposition of the wire connectors after the connecting process of a plurality of wire connectors
Definitions
- a stem for a semiconductor package is used to mount a semiconductor device, such as a light emitting device or the like, in the semiconductor package.
- a known structure for the stem includes a through hole is formed in a rectangular base, and a lead terminal is sealed inside the through hole using glass.
- the base has a device mounting surface on which the semiconductor device is mounted. After the mounting the semiconductor device on the device mounting surface of the base, the stem for the semiconductor package is electrically connected to the lead terminal, and a cap is bonded to a peripheral portion of the base by welding or the like, to form the semiconductor package (refer to Japanese Laid-Open Patent Publication No. 2004-235212, for example).
- the flatness of the base is important from a viewpoint of bonding the base and the cap while maintaining the airtightness. Hence, there are demands to reduce warping of the base in the stem for the semiconductor package.
- a stem for a semiconductor package includes a plate; a frame, positioned on an outer periphery of the plate in a plan view, and bonded to the plate; and a lead terminal held in a state insulated from the plate and the frame, wherein the plate protrudes from a top surface and a bottom surface of the frame, and a protruding amount of the plate from the top surface and a protruding amount of the plate from the bottom surface are the same.
- FIG. 1A and FIG. 1B are diagrams illustrating an example of a stem for a semiconductor package according to one embodiment.
- FIG. 2A and FIG. 2B are diagrams illustrating the example of the step for the semiconductor package according to one embodiment.
- FIG. 1A , FIG. 1B , FIG. 2A , and FIG. 2B are diagrams illustrating an example of the stem for the semiconductor package according to one embodiment of the present embodiment.
- FIG. 1A is a perspective view viewed from a top of the stems
- FIG. 1B is a perspective view viewed from a bottom of the stems.
- FIG. 2A is a perspective view, in partial cross section, viewed from the top of the stems
- FIG. 2B is view, in partial cross section, illustrating the stem.
- a stem 1 for a semiconductor package includes a plate 10 , a frame 20 , a plurality of lead holding members 30 , a plurality of lead terminals 40 , and a plurality of sealing parts 50 .
- the plate 10 has a rectangular shape in a plan view, for example, and includes a top surface 10 a and a bottom surface 10 b .
- the plate 10 may have a length of approximately 40 mm to approximately 60 mm in a longitudinal direction, a length of approximately 20 mm to approximately 40 mm in a transverse (or short) direction, and thickness of approximately 3 mm to approximately 4 mm, for example.
- a plurality of semiconductor devices such as a semiconductor laser or the like, can be mounted on the top surface 10 a of the plate 10 .
- the top surface 10 a of the plate 10 forms a device mounting surface on which a plurality of semiconductor devices can be mounted.
- the bottom surface 10 b of the plate 10 may thermally connect to a heat sink or the like, and can be used as a heat dissipation (or heat sink) surface for dissipating the heat generated from the semiconductor device.
- a thermal conductivity of the plate 10 is preferably greater than a thermal conductivity of the frame 20 .
- Ceramics or metals may be used as a material forming the plate 10 , for example, but a metal is preferably used for the plate 10 in order to improve the heat dissipation.
- the metals preferably used for the plate 10 include copper, copper alloys, or the like, for example.
- a plan view of an object refers to the view of the object viewed from a normal direction with respect to the top surface 10 a of the plate 10 .
- a planar shape of the object refers to the shape of the object in the plan view viewed from the normal direction with respect to the top surface 10 a of the plate 10 .
- the frame 20 is positioned on an outer periphery of the plate 10 in the plan view, and is bonded to the plate 10 .
- the frame 20 has a picture frame shape in the plan view, for example.
- An outer edge of the frame 20 may have a length of approximately 50 mm to approximately 70 mm in the longitudinal direction, a length of approximately 30 mm to approximately 50 mm in the transverse direction, and a thickness of approximately 1 mm to approximately 2 mm, for example.
- An inner edge of the frame 20 is determined according to the size of the plate 10 , and has a size similar to the size of an outer edge of the plate 10 .
- Metals such as iron, stainless steel, or the like may preferably be used as a material forming the frame 20 , for example.
- the entire inner side surface of the frame 20 is bonded to a side surface of the plate 10 .
- a metal bonding material for example, may be used to bond the inner side surface of the frame 20 to the side surface of the plate 10 .
- An example of the metal bonding material includes silver braze, for example.
- the frame 20 includes a plurality of through holes 20 x which penetrate the frame 20 from a top surface 20 a to a bottom surface 20 b of the frame 20 .
- the planar shape of the through holes 20 x is a circular shape, for example, and a diameter of this circular shape is approximately 1.5 mm to approximately 3.0 mm, for example.
- the lead holding member 30 is bonded to the bottom surface 20 b of the frame 20 near each of the through holes 20 x .
- Metals such as iron, stainless steel, or the like, for example, may be used as a material forming the lead holding member 30 .
- the frame 20 and the lead holding members 30 are preferably made of the same material, in order to reduce warping caused by a difference, in thermal expansions of the frame 20 and the lead holding member 30 during brazing.
- the lead holding member 30 includes a cylindrical large diameter portion 31 , and a cylindrical small diameter portion 32 having a diameter smaller than a diameter of the large diameter portion 31 .
- the large diameter portion 31 and the small diameter portion 32 are formed concentrically.
- the small diameter portion 32 is inserted into the through hole 20 x and bonded to the frame 20 . More particularly, a side surface of the small diameter portion 32 and an inner side surface of the through hole 20 x are bonded to each other, and a top surface of the large diameter portion 31 and the bottom surface 20 b of the frame 20 are bonded to each other.
- a metal bonding material may be used to bond the frame 20 to the lead holding member 30 .
- An example of the metal bonding material includes silver braze, for example.
- the lead holding member 30 includes a through hole 30 x which penetrates the large diameter portion 31 and the small diameter portion 32 in a thickness direction.
- the lead holding member 30 is fixed to the bottom surface 20 b of the frame 20 , so that the through hole 30 x and the through hole 20 x communicate with each other.
- the lead terminal 40 is inserted into the through hole 30 x .
- the lead terminal 40 is held in a state insulated from the plate 10 , the frame 20 , and the lead holding member 30 . More particularly, the lead terminal 40 is held inside the through hole 30 x of the lead holding member 30 , without making contact with the inner side surfaces of the through hole 20 x and the through hole 30 x .
- the lead terminal 40 electrically connects the semiconductor device mounted on the plate 10 to an external part (not illustrated).
- Nickel-cobalt ferrous alloys such as Kovar (registered trademark), iron-nickel alloys, or like, for example, may be used as a material forming the lead terminal 40 .
- An end of the lead terminal 40 may protrude from the through hole 30 x .
- the end of the lead terminal 40 may protrude from the top surface 20 a of the frame 20 .
- the lead terminal 40 is preferably held by the lead holding member 30 so as not to protrude from the top surface 20 a of the frame 20 .
- the lead holding member 30 may have a thickness of approximately 1 mm to approximately 3 mm, for example.
- the lead terminals 40 can be held more rigidly, by making the thickness of the lead holding member 30 approximately 1 mm to approximately 3 mm.
- the sealing part 50 made of an insulating material, is provided on an outer periphery of the lead terminal 40 inside the through hole 30 x .
- the lead terminal 40 is held inside the through hole 30 x of the lead holding member 30 via the insulating sealing part 50 .
- one through hole 30 x is provided with respect to each of the plurality of lead terminals 40 . Accordingly, a portion between the lead terminal 40 and the lead holding member 30 can be positively sealed by the insulating sealing part 50 .
- a glass material for example, may be used as a material forming the sealing part 50 .
- the material forming the sealing part 50 preferably has a coefficient of thermal expansion relatively close to coefficients of thermal expansion of the lead holding member 30 and the lead terminal 40 .
- An example of such a material includes borosilicate glass, for example.
- the plate 10 is formed to be thicker than the frame 20 .
- the top surface 10 a of the plate 10 protrudes from the top surface 20 a of the frame 20
- the bottom surface 10 b of the plate 10 protrudes from the bottom surface 20 b of the frame 20 .
- the entire top surface 10 a of the plate 10 protrudes from the top surface 20 a of the frame 20
- the entire bottom surface 10 b of the plate 10 protrudes from the bottom surface 20 b of the frame 20 .
- a protruding amount T 1 of the top surface 10 a of the plate 10 from the top surface 20 a of the frame 20 is the same as a protruding amount T 2 of the bottom surface 10 b of the plate 10 from the bottom surface 20 b of the frame 20 .
- Protruding amounts T 1 and T 2 are in a range of approximately 0.5 mm to approximately 1.5 mm, for example.
- the protruding amount T 1 and the protruding amount T 2 are described as being the same, it is referring to a case where the protruding amount T 2 falls within a range of the protruding amount T 1 ⁇ 100 ⁇ m.
- a dedicated jig having a high dimensional accuracy may be used for the bonding between the plate 10 and the frame 20 .
- the stem 1 for the semiconductor package is electrically connected to the lead terminal 40 , and a cap (not illustrated) is bonded to the top surface 20 a of the frame 20 by welding or the like, to form the semiconductor package.
- the warping of the plate 10 and the frame 20 may cause a problem. If the warping of the plate 10 and the frame 20 is large, it becomes difficult to bond the cap to the top surface 20 a of the frame 20 by the welding or the like.
- the present inventor made a comparative stem A for a semiconductor package, by replacing the frame with a rectangular second plate larger than the plate, and bonding a rectangular plate on the second plate, to expose an outer periphery of the second plate around the plate.
- the plate was made of copper
- the second plate was made of iron
- the lead terminal was sealed inside a through hole provided in the outer periphery of the second plate, using glass.
- the warping of the plate and the second plate was approximately 200 ⁇ m. In this state, it was difficult to bond the second plate and the cap while maintaining airtightness.
- the present inventor made a stem B for a semiconductor package having a structure similar to that of the stem 1 for the semiconductor package described above, by making the plate protrude from the top surface and the bottom surface of the frame, and making the protruding amount of the plate from the top surface of the frame the same as the protruding amount of the plate from the bottom surface of the frame.
- the lead terminal was sealed inside the through hole provided in the frame, using glass, but without using the lead holding member.
- stem B for the semiconductor package the materials used for the plate and the frame, and the thickness of frame material, were the same as those of the stem A for the semiconductor package, and the thickness of the plate was set so that the protruding amount from the top and bottom surfaces of the frame becomes 1 mm.
- the warping of the plate and frame was approximately 100 ⁇ m. In this state, it was possible to bond the frame and the cap while maintaining airtightness.
- the stem 1 for the semiconductor package was made under the same conditions as the stem B for the semiconductor package, except that the lead terminal 40 was sealed inside the through hole 20 x provided in the frame 20 , using glass and using the lead holding member 30 made of iron.
- the warping of the plate 10 and the frame 20 was 50 ⁇ m or less. In this state, it was possible to bond the frame 20 and the cap while maintaining airtightness, and the airtightness was further improved.
- the warping was evaluated by measuring irregularities using a non-contact three-dimensional measuring machine. More particularly, a difference between a lowest point of a height of the plate and a highest point of height of the plate was measured, to determine a magnitude of the warping of the plate. Similarly, a difference between a lowest point of a height of the frame and a highest point of the height of the frame was measured, to determine a magnitude of the warping of the frame.
- the plate is designed with emphasis on the heat dissipation, while the frame is designed with emphasis on, the airtightness utilizing the difference between the coefficients of thermal expansion of the frame and the sealing part which seals the lead terminal. Accordingly, different materials are used for the plate and the frame. For this reason, stress is generated by the brazing performed at approximately 800° C., for example, due to the difference between the coefficients of thermal expansion of the plate and the frame, thereby generating the warping.
- the plate 10 protrudes from the top surface 20 a and the bottom surface 20 b of the frame 20 , and the protruding amount T 1 from the top surface 20 a and the protruding amount T 2 from the bottom surface 20 b are the same, thereby improving a balance above and below the frame 20 .
- the stress caused by the difference between the coefficients of thermal expansion of the plate 10 and the frame 20 is relaxed, and the warping is reduced, thereby enabling the bonding of the frame 20 and the cap.
- one lead terminal 40 is inserted into one lead holding member 30 .
- the lead holding member from a single plate having a plurality of through holes, and to insert the plurality of lead terminals 40 into the plurality of through holes, respectively.
- the plate shaped lead holding member and the frame 20 would require a large area to be bonded by the brazing, thereby adversely affecting the warping of the frame 20 , that is, increasing the warping of the frame 20 .
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Semiconductor Lasers (AREA)
- Led Device Packages (AREA)
- Packaging Frangible Articles (AREA)
Abstract
A stem for a semiconductor package, includes a plate, a frame, positioned on an outer periphery of the plate in a plan view, and bonded to the plate, and a lead terminal held in a state insulated from the plate and the frame. The plate protrudes from a top surface and a bottom surface of the frame, and a protruding amount of the plate from the top surface and a protruding amount of the plate from the bottom surface are the same.
Description
- This application is based upon and claims priority to Japanese Patent Application No. 2020-203393, filed on Dec. 8, 2020, the entire contents of which are incorporated herein by reference.
- Certain aspects of the embodiments discussed herein are related to stems for semiconductor packages.
- A stem for a semiconductor package is used to mount a semiconductor device, such as a light emitting device or the like, in the semiconductor package. For example, a known structure for the stem includes a through hole is formed in a rectangular base, and a lead terminal is sealed inside the through hole using glass. The base has a device mounting surface on which the semiconductor device is mounted. After the mounting the semiconductor device on the device mounting surface of the base, the stem for the semiconductor package is electrically connected to the lead terminal, and a cap is bonded to a peripheral portion of the base by welding or the like, to form the semiconductor package (refer to Japanese Laid-Open Patent Publication No. 2004-235212, for example).
- In the stem for the semiconductor package described above, the flatness of the base is important from a viewpoint of bonding the base and the cap while maintaining the airtightness. Hence, there are demands to reduce warping of the base in the stem for the semiconductor package.
- Accordingly, it is an object in one aspect of the embodiments to provide a stem for a semiconductor package, which can reduce warping of an object to which a cap is bonded.
- According to one aspect of the embodiments, a stem for a semiconductor package, includes a plate; a frame, positioned on an outer periphery of the plate in a plan view, and bonded to the plate; and a lead terminal held in a state insulated from the plate and the frame, wherein the plate protrudes from a top surface and a bottom surface of the frame, and a protruding amount of the plate from the top surface and a protruding amount of the plate from the bottom surface are the same.
- The object and advantages of the embodiments will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
- It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and not restrictive of the invention, as claimed.
-
FIG. 1A andFIG. 1B are diagrams illustrating an example of a stem for a semiconductor package according to one embodiment. -
FIG. 2A andFIG. 2B are diagrams illustrating the example of the step for the semiconductor package according to one embodiment. - Preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, those parts that are the same are designated by the same reference numerals, and a repeated description of the same parts may be omitted.
- A description will now be given of a stem for a semiconductor package, according to each embodiment of the present invention.
-
FIG. 1A ,FIG. 1B ,FIG. 2A , andFIG. 2B are diagrams illustrating an example of the stem for the semiconductor package according to one embodiment of the present embodiment.FIG. 1A is a perspective view viewed from a top of the stems, andFIG. 1B is a perspective view viewed from a bottom of the stems.FIG. 2A is a perspective view, in partial cross section, viewed from the top of the stems, andFIG. 2B is view, in partial cross section, illustrating the stem. - Referring to
FIG. 1A throughFIG. 2B , astem 1 for a semiconductor package according to this embodiment includes aplate 10, aframe 20, a plurality oflead holding members 30, a plurality oflead terminals 40, and a plurality ofsealing parts 50. - The
plate 10 has a rectangular shape in a plan view, for example, and includes atop surface 10 a and abottom surface 10 b. Theplate 10 may have a length of approximately 40 mm to approximately 60 mm in a longitudinal direction, a length of approximately 20 mm to approximately 40 mm in a transverse (or short) direction, and thickness of approximately 3 mm to approximately 4 mm, for example. - A plurality of semiconductor devices, such as a semiconductor laser or the like, can be mounted on the
top surface 10 a of theplate 10. In other words, thetop surface 10 a of theplate 10 forms a device mounting surface on which a plurality of semiconductor devices can be mounted. Thebottom surface 10 b of theplate 10 may thermally connect to a heat sink or the like, and can be used as a heat dissipation (or heat sink) surface for dissipating the heat generated from the semiconductor device. - From a viewpoint of the heat dissipation of the mounted semiconductor device, a thermal conductivity of the
plate 10 is preferably greater than a thermal conductivity of theframe 20. Ceramics or metals may be used as a material forming theplate 10, for example, but a metal is preferably used for theplate 10 in order to improve the heat dissipation. The metals preferably used for theplate 10 include copper, copper alloys, or the like, for example. - In this specification, a plan view of an object refers to the view of the object viewed from a normal direction with respect to the
top surface 10 a of theplate 10. Further, a planar shape of the object refers to the shape of the object in the plan view viewed from the normal direction with respect to thetop surface 10 a of theplate 10. - The
frame 20 is positioned on an outer periphery of theplate 10 in the plan view, and is bonded to theplate 10. Theframe 20 has a picture frame shape in the plan view, for example. An outer edge of theframe 20 may have a length of approximately 50 mm to approximately 70 mm in the longitudinal direction, a length of approximately 30 mm to approximately 50 mm in the transverse direction, and a thickness of approximately 1 mm to approximately 2 mm, for example. An inner edge of theframe 20 is determined according to the size of theplate 10, and has a size similar to the size of an outer edge of theplate 10. Metals such as iron, stainless steel, or the like may preferably be used as a material forming theframe 20, for example. For example, the entire inner side surface of theframe 20 is bonded to a side surface of theplate 10. A metal bonding material, for example, may be used to bond the inner side surface of theframe 20 to the side surface of theplate 10. An example of the metal bonding material includes silver braze, for example. - The
frame 20 includes a plurality of throughholes 20 x which penetrate theframe 20 from atop surface 20 a to abottom surface 20 b of theframe 20. The planar shape of thethrough holes 20 x is a circular shape, for example, and a diameter of this circular shape is approximately 1.5 mm to approximately 3.0 mm, for example. Thelead holding member 30 is bonded to thebottom surface 20 b of theframe 20 near each of the throughholes 20 x. Metals such as iron, stainless steel, or the like, for example, may be used as a material forming thelead holding member 30. Theframe 20 and thelead holding members 30 are preferably made of the same material, in order to reduce warping caused by a difference, in thermal expansions of theframe 20 and thelead holding member 30 during brazing. - The
lead holding member 30 includes a cylindricallarge diameter portion 31, and a cylindricalsmall diameter portion 32 having a diameter smaller than a diameter of thelarge diameter portion 31. Thelarge diameter portion 31 and thesmall diameter portion 32 are formed concentrically. Thesmall diameter portion 32 is inserted into the throughhole 20 x and bonded to theframe 20. More particularly, a side surface of thesmall diameter portion 32 and an inner side surface of the throughhole 20 x are bonded to each other, and a top surface of thelarge diameter portion 31 and thebottom surface 20 b of theframe 20 are bonded to each other. A metal bonding material, for example, may be used to bond theframe 20 to thelead holding member 30. An example of the metal bonding material includes silver braze, for example. - The
lead holding member 30 includes a throughhole 30 x which penetrates thelarge diameter portion 31 and thesmall diameter portion 32 in a thickness direction. Thelead holding member 30 is fixed to thebottom surface 20 b of theframe 20, so that the throughhole 30 x and the throughhole 20 x communicate with each other. Thelead terminal 40 is inserted into the throughhole 30 x. Thelead terminal 40 is held in a state insulated from theplate 10, theframe 20, and thelead holding member 30. More particularly, thelead terminal 40 is held inside the throughhole 30 x of thelead holding member 30, without making contact with the inner side surfaces of the throughhole 20 x and the throughhole 30 x. Thelead terminal 40 electrically connects the semiconductor device mounted on theplate 10 to an external part (not illustrated). Nickel-cobalt ferrous alloys such as Kovar (registered trademark), iron-nickel alloys, or like, for example, may be used as a material forming thelead terminal 40. - An end of the
lead terminal 40 may protrude from the throughhole 30 x. In addition, the end of thelead terminal 40 may protrude from thetop surface 20 a of theframe 20. However, from a viewpoint of shortening the length of thelead terminal 40, thelead terminal 40 is preferably held by thelead holding member 30 so as not to protrude from thetop surface 20 a of theframe 20. By shortening the length of thelead terminal 40, it is possible to reduce the resonance caused by an ultrasonic frequency which is likely generated when the semiconductor device mounted on theplate 10 and thelead terminals 40 are bonded by ultrasonic wire bonding. Thelead holding member 30 may have a thickness of approximately 1 mm to approximately 3 mm, for example. Thelead terminals 40 can be held more rigidly, by making the thickness of thelead holding member 30 approximately 1 mm to approximately 3 mm. - The sealing
part 50, made of an insulating material, is provided on an outer periphery of thelead terminal 40 inside the throughhole 30 x. In other words, thelead terminal 40 is held inside the throughhole 30 x of thelead holding member 30 via the insulating sealingpart 50. Preferably, one throughhole 30 x is provided with respect to each of the plurality oflead terminals 40. Accordingly, a portion between thelead terminal 40 and thelead holding member 30 can be positively sealed by the insulating sealingpart 50. - A glass material, for example, may be used as a material forming the sealing
part 50. In order to seal the semiconductor device mounted on theplate 10 airtight, the material forming the sealingpart 50 preferably has a coefficient of thermal expansion relatively close to coefficients of thermal expansion of thelead holding member 30 and thelead terminal 40. An example of such a material includes borosilicate glass, for example. - In the
stem 1 for the semiconductor package, theplate 10 is formed to be thicker than theframe 20. Thetop surface 10 a of theplate 10 protrudes from thetop surface 20 a of theframe 20, and thebottom surface 10 b of theplate 10 protrudes from thebottom surface 20 b of theframe 20. For example, the entiretop surface 10 a of theplate 10 protrudes from thetop surface 20 a of theframe 20, and theentire bottom surface 10 b of theplate 10 protrudes from thebottom surface 20 b of theframe 20. - A protruding amount T1 of the
top surface 10 a of theplate 10 from thetop surface 20 a of theframe 20 is the same as a protruding amount T2 of thebottom surface 10 b of theplate 10 from thebottom surface 20 b of theframe 20. Protruding amounts T1 and T2 are in a range of approximately 0.5 mm to approximately 1.5 mm, for example. In this specification, when the protruding amount T1 and the protruding amount T2 are described as being the same, it is referring to a case where the protruding amount T2 falls within a range of the protruding amount T1±100 μm. In order to make the protruding amount T1 and the protruding amount T2 the same, a dedicated jig having a high dimensional accuracy may be used for the bonding between theplate 10 and theframe 20. - After the mounting the semiconductor device on the
top surface 10 a (that is, the device mounting surface) of theplate 10, thestem 1 for the semiconductor package is electrically connected to thelead terminal 40, and a cap (not illustrated) is bonded to thetop surface 20 a of theframe 20 by welding or the like, to form the semiconductor package. In this case, the warping of theplate 10 and theframe 20 may cause a problem. If the warping of theplate 10 and theframe 20 is large, it becomes difficult to bond the cap to thetop surface 20 a of theframe 20 by the welding or the like. - For consideration purposes, the present inventor made a comparative stem A for a semiconductor package, by replacing the frame with a rectangular second plate larger than the plate, and bonding a rectangular plate on the second plate, to expose an outer periphery of the second plate around the plate. The plate was made of copper, the second plate was made of iron, and the lead terminal was sealed inside a through hole provided in the outer periphery of the second plate, using glass. In the stem A for the semiconductor package, the warping of the plate and the second plate was approximately 200 μm. In this state, it was difficult to bond the second plate and the cap while maintaining airtightness.
- Next, the present inventor made a stem B for a semiconductor package having a structure similar to that of the
stem 1 for the semiconductor package described above, by making the plate protrude from the top surface and the bottom surface of the frame, and making the protruding amount of the plate from the top surface of the frame the same as the protruding amount of the plate from the bottom surface of the frame. However, in the stem B for the semiconductor package, the lead terminal was sealed inside the through hole provided in the frame, using glass, but without using the lead holding member. In stem B for the semiconductor package, the materials used for the plate and the frame, and the thickness of frame material, were the same as those of the stem A for the semiconductor package, and the thickness of the plate was set so that the protruding amount from the top and bottom surfaces of the frame becomes 1 mm. In stem B for the semiconductor package, the warping of the plate and frame was approximately 100 μm. In this state, it was possible to bond the frame and the cap while maintaining airtightness. - Next, the present inventor made the
stem 1 for the semiconductor package. Thestem 1 for the semiconductor package was made under the same conditions as the stem B for the semiconductor package, except that thelead terminal 40 was sealed inside the throughhole 20 x provided in theframe 20, using glass and using thelead holding member 30 made of iron. In thestem 1 for the semiconductor package, the warping of theplate 10 and theframe 20 was 50 μm or less. In this state, it was possible to bond theframe 20 and the cap while maintaining airtightness, and the airtightness was further improved. - The warping was evaluated by measuring irregularities using a non-contact three-dimensional measuring machine. More particularly, a difference between a lowest point of a height of the plate and a highest point of height of the plate was measured, to determine a magnitude of the warping of the plate. Similarly, a difference between a lowest point of a height of the frame and a highest point of the height of the frame was measured, to determine a magnitude of the warping of the frame.
- Generally, in the stem for the semiconductor package, the plate is designed with emphasis on the heat dissipation, while the frame is designed with emphasis on, the airtightness utilizing the difference between the coefficients of thermal expansion of the frame and the sealing part which seals the lead terminal. Accordingly, different materials are used for the plate and the frame. For this reason, stress is generated by the brazing performed at approximately 800° C., for example, due to the difference between the coefficients of thermal expansion of the plate and the frame, thereby generating the warping.
- However, according to the structure of the
stem 1 for the semiconductor package, theplate 10 protrudes from thetop surface 20 a and thebottom surface 20 b of theframe 20, and the protruding amount T1 from thetop surface 20 a and the protruding amount T2 from thebottom surface 20 b are the same, thereby improving a balance above and below theframe 20. For this reason, it may be regarded that the stress caused by the difference between the coefficients of thermal expansion of theplate 10 and theframe 20 is relaxed, and the warping is reduced, thereby enabling the bonding of theframe 20 and the cap. - In the
stem 1 for the semiconductor package, onelead terminal 40 is inserted into onelead holding member 30. For example, it is conceivable to form the lead holding member from a single plate having a plurality of through holes, and to insert the plurality oflead terminals 40 into the plurality of through holes, respectively. However, in this conceivable case, the plate shaped lead holding member and theframe 20 would require a large area to be bonded by the brazing, thereby adversely affecting the warping of theframe 20, that is, increasing the warping of theframe 20. On the contrary, by inserting onelead terminal 40 into onelead holding member 30 as in thestem 1 for the semiconductor package, the area of thelead holding member 30 and theframe 20 to be bonded by the brazing can be reduced, thereby reducing the adverse effects on the warping of theframe 20. - Although the preferred embodiments have been described in detail above, various variations, modifications, and substitutions may be made to the embodiments described above without departing from the scope of the present disclosure.
- According to each of the embodiments, it is possible to provide a stem for a semiconductor package, which can reduce warping of an object to which a cap is bonded.
- All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
Claims (14)
1. A stem for a semiconductor package, comprising:
a plate having a rectangular shape in a plan view;
a frame having a picture frame shape in the plan view, the frame being positioned on an outer periphery of the plate in the plan view and bonded to the plate; and
a lead terminal held in a state insulated from the plate and the frame,
wherein the plate protrudes from a top surface and a bottom surface of the frame, and a protruding amount of the plate from the top surface and a protruding amount of the plate from the bottom surface are the same.
2. The stem for the semiconductor package as claimed in claim 1 , wherein
an entire inner side surface of the frame is bonded to a side surface of the plate.
3. The stein for the semiconductor package as claimed in claim 1 , wherein an entire top surface of the plate protrudes from the top surface of the frame, and an entire bottom surface of the plate protrudes from the bottom surface of the frame.
4. The stem for the semiconductor package as claimed in claim 1 , further comprising:
a first through hole penetrating the frame; and
a lead holding member having a second through hole,
wherein the lead holding member is fixed to the bottom surface of the frame so that the second through hole communicates with the first through hole, and
wherein the lead terminal is held inside the second through hole without making contact with inner side surfaces of the first through hole and the second through hole, respectively.
5. The stem for the semiconductor package as claimed in claim 4 , wherein an end of the lead terminal is held by the lead holding member so as not to protrude from the top surface of the frame.
6. The stem for the semiconductor package as claimed in claim 4 , wherein the lead terminal is held inside the second through hole via an insulating sealing part.
7. The stem for the semiconductor package as claimed in claim 4 , wherein the frame and the lead holding member are made of the same material.
8. The stem for the semiconductor package as claimed in claim 1 , wherein the plate and the frame are made of metals, respectively, and a thermal conductivity of the plate is greater than a thermal conductivity of the frame.
9. The stem for the semiconductor device as claimed in claim 4 , wherein
the lead holding member includes a first portion, a second portion having a diameter smaller than a diameter of the first portion, and the second through hole penetrating the first portion and the second portion,
the first portion and the second portion are formed concentrically,
the second portion is inserted into the first through hole and bonded to the frame, and
a top surface of the first portion and the bottom surface of the frame are bonded to each other.
10. The stem for the semiconductor package as claimed in claim 3 , further comprising:
a first through hole penetrating the frame; and
a lead holding member having a second through hole,
wherein the lead holding member is fixed to the bottom surface of the frame so that the second through hole communicates with the first through hole, and
wherein the lead terminal is held inside the second through hole without making contact with inner side surfaces of the first through hole and the second through hole, respectively.
11. The stem for the semiconductor package as claimed in claim 10 , wherein an end of the lead terminal is held by the lead holding member so as not to protrude from the top surface of the frame.
12. The stem for the semiconductor package as claimed in claim 10 , wherein the lead terminal is held inside the second through hole via an insulating sealing part.
13. The stem for the semiconductor package as claimed in claim 10 , wherein the frame and the lead holding member are made of the same material.
14. The stem for the semiconductor package as claimed in claim 10 , wherein the plate and the frame are made of metals, respectively, and a thermal conductivity of the plate is greater than a thermal conductivity of the frame.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2020-203393 | 2020-12-08 | ||
JPJP2020-203393 | 2020-12-08 | ||
JP2020203393A JP2022090839A (en) | 2020-12-08 | 2020-12-08 | Stem for semiconductor package |
Publications (2)
Publication Number | Publication Date |
---|---|
US20220181272A1 true US20220181272A1 (en) | 2022-06-09 |
US11373961B1 US11373961B1 (en) | 2022-06-28 |
Family
ID=81849237
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US17/153,004 Active US11373961B1 (en) | 2020-12-08 | 2021-01-20 | Stem for semiconductor package |
Country Status (4)
Country | Link |
---|---|
US (1) | US11373961B1 (en) |
JP (1) | JP2022090839A (en) |
CN (1) | CN114614339A (en) |
TW (1) | TW202224118A (en) |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004128273A (en) * | 2002-10-03 | 2004-04-22 | Sharp Corp | Light emitting element |
JP2004235212A (en) | 2003-01-28 | 2004-08-19 | Matsushita Electric Ind Co Ltd | Airtight terminal and semiconductor device using the same |
US20100252856A1 (en) * | 2009-01-28 | 2010-10-07 | Coretek Opto Corp. | Header structure of opto-electronic element and opto-electronic element using the same |
JP6430160B2 (en) * | 2014-07-07 | 2018-11-28 | 日本オクラロ株式会社 | Optical module and optical module manufacturing method |
JP7240160B2 (en) * | 2018-12-11 | 2023-03-15 | 新光電気工業株式会社 | stem |
-
2020
- 2020-12-08 JP JP2020203393A patent/JP2022090839A/en active Pending
-
2021
- 2021-01-19 TW TW110101911A patent/TW202224118A/en unknown
- 2021-01-19 CN CN202110072098.1A patent/CN114614339A/en active Pending
- 2021-01-20 US US17/153,004 patent/US11373961B1/en active Active
Also Published As
Publication number | Publication date |
---|---|
TW202224118A (en) | 2022-06-16 |
CN114614339A (en) | 2022-06-10 |
US11373961B1 (en) | 2022-06-28 |
JP2022090839A (en) | 2022-06-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7321161B2 (en) | LED package assembly with datum reference feature | |
US20200273814A1 (en) | Semiconductor package | |
JP6225834B2 (en) | Semiconductor light emitting device and manufacturing method thereof | |
US11373961B1 (en) | Stem for semiconductor package | |
US11349278B2 (en) | Stem for semiconductor package, and semiconductor package | |
JP2023521798A (en) | Hermetic surface mount package for semiconductor side-emitting lasers and method of forming same | |
JP2001244355A (en) | Packcage for semiconductor element | |
JP2010080562A (en) | Package for housing electronic component | |
JP7014645B2 (en) | Semiconductor light emitting device | |
JP4556732B2 (en) | Semiconductor device and manufacturing method thereof | |
JP2007012718A (en) | Electronic component housing package and electronic device | |
JP6485518B2 (en) | Semiconductor light emitting device and manufacturing method thereof | |
US20240113494A1 (en) | Cap housing, cap, and semiconductor device | |
JP2019075460A (en) | Semiconductor light emitting element and semiconductor light emitting device | |
US20230154818A1 (en) | Header for semiconductor package | |
US20220181525A1 (en) | Header for semiconductor package, and semiconductor package | |
JP2004266188A (en) | Package for semiconductor device, its manufacturing method and semiconductor device using it | |
JP4824063B2 (en) | Package for semiconductor devices | |
JP2014003134A (en) | High heat dissipation type electronic component storing package | |
JPWO2017038582A1 (en) | Semiconductor element storage package and semiconductor device | |
JP2009014935A (en) | Package for optical communication | |
JP2004253409A (en) | Optical semiconductor element accommodating package and optical semiconductor device | |
JP2796178B2 (en) | Glass terminals for electronic components | |
JPH04302458A (en) | Semiconductor device housing apparatus | |
JP2004294782A (en) | Optical semiconductor element-housing package and optical semiconductor device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SHINKO ELECTRIC INDUSTRIES CO., LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KATAYAMA, WATARU;REEL/FRAME:054964/0277 Effective date: 20210112 |
|
FEPP | Fee payment procedure |
Free format text: ENTITY STATUS SET TO UNDISCOUNTED (ORIGINAL EVENT CODE: BIG.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |