Two part mold for wafer scale caps

• US 7,126,216 B2
• Filed: 12/08/2003
• Issued: 10/24/2006
• Est. Priority Date: 01/10/2001
• Status: Expired due to Term

• Current Assignee: Nytell Software LLC (Intellectual Ventures LLC)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Whitehead, Jr., Carl
• Assistant Examiner(s): Mitchell, James M.
• Application Number:
  US10/728,808
• Publication Number:
  US 20040079862A1
• Time in Patent Office: 1,051 Days
• Field of Search: 257/704, 257/710, 257/666, 438/15, 438/25, 438/26, 438/51, 438/55, 438/64, 438/106, 438/112, 438/124, 438/127
• US Class Current: 257/704
• CPC Class Codes: B29C 2035/0822 using IR radiation
• CPC Class Codes: B29C 2043/503 using ejector pins, rods
• CPC Class Codes: B29C 33/0022 Multi-cavity moulds B29C33/301 takes precedence
• CPC Class Codes: B29C 33/3842 Manufacturing moulds, e.g. shaping the mould surface by machining
• CPC Class Codes: B29C 43/36 Moulds for making articles of definite length, i.e. discrete articles
• CPC Class Codes: B81C 1/00333 Aspects relating to packaging of MEMS devices, not covered by groups B81C1/00269 - B81C1/00325
• CPC Class Codes: B81C 2203/0109 Bonding an individual cap on the substrate
• CPC Class Codes: B81C 2203/0127 Using a carrier for applying a plurality of packaging lids to the system wafer
• CPC Class Codes: H01L 21/50 Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/1461 MEMS
• CPC Class Codes: Y10S 257/924 with passive device, e.g. capacitor, or battery, as integral part of housing or housing element, e.g. cap

Abstract

The invention provides a two part mold for forming wafer scale caps. The mold has a first half and a second half. The first half and second half, when brought together defining mold cavities for wafer scale caps. The caps have central areas surrounded by sidewalls and the side walls having free edges. In preferred embodiments, the mold is made from a semiconductor material.

Claims

1. A separable mold for forming wafer scale caps, the separable mold comprising:

a first semiconductor mold element;

a first release element which is releaseably coupled to the first mold element to form an upper mold section;

a second semiconductor mold element;

a second release element which is releasably coupled to the second mold element to form a lower mold section;

mold cavities being defined by the upper mold section being positioned adjacently to the lower mold section, each cavity having a shape comprising;

a central cavity areas surrounded by sidewall cavity areas having free edges.

2. The mold of claim 1, wherein:

the first mold element of the mold has a lower surface in which recesses are formed;

the second mold element having an upper surface in which grooves are fanned;

the recesses and grooves defining the plurality of mold cavities.

3. The mold of claim 2, wherein:

the first mold element includes first holes formed therethrough;

the first holes are located in registry with the recesses;

the first release element having first pins projecting therefrom;

the pins located in registry with the first holes;

the first mold element having a thickness in the area of the first holes, the first pins being longer than the thickness;

the first release element having a first position in which the pins are flush with an interior end of the first holes; and

there being a gap between the first mold element and the first release element when the first release element is in the first position.

4. The mold of claim 3, wherein:

the first and second halves and the first half release wafer are comprised of a semiconductor that is substantially transparent to infrared light of a wavelength of about 1000–

5000 nm.

5. The mold of claim 2, wherein:

the second mold element includes second holes formed therethrough;

the second release portion having a second pins projecting Therefrom;

the second pins located in registry with the second holes;

the second mold element having a thickness in the area of the second boles, the pins being longer than the thickness;

the second release element having a first position in which the pins are flush with an interior end of the second holes;

there being a second gap between the second mold element and the second release element when the second release element is in the first position.

6. The mold of claim 5, wherein:

the second holes are located in registry wit the grooves.

7. The mold of claim 2, wherein:

the first mold portion includes first holes formed therethrough;

the first holes located in registry with the recesses;

the first release portion having first pins projecting therefrom;

the first pins located in registry with the first holes;

the first mold element having a thickness in the area of the first holes, the first pins being longer than the thickness;

the first release element having a first position in which the first pins are flush with an interior end of the first holes;

there being a gap between the first mold element and the first release element when the first release element is in the first position; and

the second mold portion includes second holes formed through it;

the second release portion having second pins projecting therefrom;

the second pins located in registry with the second holes;

the second mold element having a thickness in the area of the second holes, the pins being longer than the thickness;

the second release element having a second position in which the second pins are flush with an interior end of the second holes;

there being a second gap between the second half and the second release element when the second release element is in the first position.

8. The mold of claim 7, wherein:

the first mold element, the second mold element, the first release element and the second release element are comprised of a semiconductor that is transparent to infrared light of a wavelength of about 1000–

5000 nm.

9. The mold of claim 1, wherein:

the first and second halves are comprised of a semiconductor that is transparent to infrared light of a wavelength of about 1000–

5000 nm.

10. The mold of claim 1, wherein:

the first mold element has first portions which separate adjacent areas; and

the second mold element has second portions which separate adjacent grooves.

11. The mold according to claim 1, wherein the first mold element, the first release element, the second mold element and the second release element are separate elements.