EP0405865A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of connecting opposed pairs of contacts of detector and readout microchips in a hybrid detector array assembly
Assignee: Raytheon Co
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Filing: 1990-06-22
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Granted: —
•
Expires: 2010-06-22
Abstract
Abstract Method for improving particular interconnect pads for microcircuitry so that they provide more compliant interconnections between opposed pairs of contacts of the microchips (42,44) in a hybrid detector array assembly. The individual tubes (34) of prior art interconnect pads are filled with indium and are then etched away to leave indium columns (40) of increased height, relative to the indium bumps (46) that have heretofore been used in the contact connections of hybrid detector array assemblies. Other materials may be substituted for the indium and a number of variants of the process are also disclosed.
Inventors
- 👤 Willliam C. Hu
- 👤 Ernest P. Longerich
- 👤 Saverio A. D'agostino
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 22:22
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/20; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/191; H10F39/193; H10F39/1935; H10W90/00; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3465; H05K3/3478; H10W72/231; H10W72/234; H10W72/251; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49169
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
129 words
The method of forming an array of connector columns of extended length for use as micro-circuit connectors in hybrid detector array assemblies comprising the steps of; selecting an interconnect pad having a plurality of hollow metal tubes mounted in a film carrier, which tubes are positioned in an array corresponding to the respective arrays of sensor contacts and readout contacts which are to be interconnected; dipping the ends of the tubes in a selected molten metal to induce the metal to fill the tubes by capillary action; cooling the interconnect pad to solidify the filler metal; etching away the metal tubes and removing the carrier; and connecting the filler metal columns between opposed pairs of contacts of respective detector and readout chips to complete the hybrid detector array assembly.
Claim 2
Independent Claim
129 words
The method of forming an array of connector columns of extended length for use as micro-circuit connectors in hybrid detector array assemblies comprising the steps of; selecting an interconnect pad having a plurality of hollow metal tubes mounted in a film carrier, which tubes are positioned in an array corresponding to the respective arrays of sensor contacts and readout contacts which are to be interconnected; dipping the ends of the tubes in a selected molten metal to induce the metal to fill the tubes by capillary action; cooling the interconnect pad to solidify the filler metal; etching away the metal tubes and removing the carrier; and connecting the filler metal columns between opposed pairs of contacts of respective detector and readout chips to complete the hybrid detector array assembly.
Claim 3
Dependent Claim
32 words
The method of claim 1 further including the step of providing each individual contact of the detector and readout chips with an indium bump to facilitate connection of a corresponding column thereto.
Claim 4
Dependent Claim
30 words
The method of claim 2 wherein the metal filled tubes of the interconnect pad are mounted to the indium bumps of the readout chip contacts prior to the etching step.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein the selected filler metal is indium.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein the selected filler metal is a predetermined solder alloy.
Claim 7
Dependent Claim
14 words
The method of claim 1 wherein the hollow metal tubes are formed of copper.
Claim 8
Dependent Claim
12 words
The method of claim 6 wherein the etching solution is ammonium sulphate.
Claim 9
Dependent Claim
29 words
The method of claim 6 further including the step of applying a layer of electroless nickel to the inner surface of the copper tubes prior to the dipping step.
Claim 10
Dependent Claim
14 words
The method of claim 1 wherein the hollow metal tubes are formed of nickel.
Claim 11
Dependent Claim
21 words
The method of claim 1 further including the steps of cleaning and preparing the interconnect pad prior to the dipping step.
Claim 12
Dependent Claim
44 words
The method of claim 10 further including the step of making a photo-reduced mask from a selected detector array pattern and wherein the step of selecting an interconnect pad comprises using a pad with a hollow metal tube array which corresponds to the mask.
Claim 13
Dependent Claim
65 words
The method of claim 4 wherein the indium columns are tapered and further including the steps of forming two sets of indium columns, installing each set to the contacts of a corresponding one of the detector and readout chips which are to be interconnected, and thereafter connecting the free ends of the indium columns together to form a double height column spacing between the chips.
Claim 14
Dependent Claim
29 words
The method of claim 12 wherein the smaller ends of the indium columns of the respective sets are connected together to develop unitary columns with a substantially hourglass shape.
Claim 15
Dependent Claim
49 words
The method of claim 12 wherein the smaller diameter ends of the indium columns of the respective sets are connected to their associated chip contacts in order to permit such connections to small dimension contact than is possible with the use of only a single set of connector columns.
Claim 16
Independent Claim
193 words
The method of fabricating a focal plane array assembly corresponding to a predetermined pattern, which focal plane array includes a plurality of indium column interconnections between opposed pairs of contacts of the respective detector and readout microchips of the focal plane array, comprising the steps of: using the focal plane array pattern to make a photo-reduced mask; using an interconnect pad with copper tubes which corresponds to the focal plane array mask and specification therefor; cleaning and preparing the interconnect pad for a dipping process; dipping the pad in molten indium and continuing the dip until the tubes are filled with indium by capillary action; transferring the indium-filled tubes to the readout chip and affixing them at one end to the individual contact pads on the readout chip by cold welding to indium bumps on the pads; etching out the original copper tubes with ammonium sulphate to release the carrier film; lifting off the carrier film from the array of indium columns; and placing the detector chip in aligned position with the indium columns and cold welding the upper ends of the columns to indium bumps on the sensor contacts by pressure welding.
Claim 17
Independent Claim
193 words
The method of fabricating a focal plane array assembly corresponding to a predetermined pattern, which focal plane array includes a plurality of indium column interconnections between opposed pairs of contacts of the respective detector and readout microchips of the focal plane array, comprising the steps of: using the focal plane array pattern to make a photo-reduced mask; using an interconnect pad with copper tubes which corresponds to the focal plane array mask and specification therefor; cleaning and preparing the interconnect pad for a dipping process; dipping the pad in molten indium and continuing the dip until the tubes are filled with indium by capillary action; transferring the indium-filled tubes to the readout chip and affixing them at one end to the individual contact pads on the readout chip by cold welding to indium bumps on the pads; etching out the original copper tubes with ammonium sulphate to release the carrier film; lifting off the carrier film from the array of indium columns; and placing the detector chip in aligned position with the indium columns and cold welding the upper ends of the columns to indium bumps on the sensor contacts by pressure welding.
Claim 18
Dependent Claim
104 words
A hybrid detector assembly for sensing infrared radiation comprising: a detector module including a plurality of infrared sensors arranged in a predetermined array; a readout module including a plurality of contact pads arranged on a substrate in a predetermined array; and means including a plurality of extended columns of a conducting material respectively situated in positions between corresponding sensors of the detector module array and contact pads of the readout module array for supporting the two modules in interconnecting relationship while accommodating the assembly to thermal effects of temperature excursions between a cold operating temperature and standard room temperature which are encountered during use.
Claim 19
Dependent Claim
104 words
A hybrid detector assembly for sensing infrared radiation comprising: a detector module including a plurality of infrared sensors arranged in a predetermined array; a readout module including a plurality of contact pads arranged on a substrate in a predetermined array; and means including a plurality of extended columns of a conducting material respectively situated in positions between corresponding sensors of the detector module array and contact pads of the readout module array for supporting the two modules in interconnecting relationship while accommodating the assembly to thermal effects of temperature excursions between a cold operating temperature and standard room temperature which are encountered during use.
Claim 20
Dependent Claim
13 words
The device of claim 21 wherein the material of said columns is indium.
Claim 21
Dependent Claim
16 words
The device of claim 21 wherein the material of said columns is an alloy of solder.
Claim 22
Dependent Claim
17 words
The device of claim 21 wherein the columns are connected to the contact pads by indium bumps.
Claim 23
Dependent Claim
18 words
The device of claim 24 wherein the columns are also connected to the infrared sensors by indium bumps.
Claim 24
Dependent Claim
21 words
The device of claim 21 wherein the respective predetermined arrays contain corresponding arrangements of like pluralities of sensors and contact pads.
Claim 25
Dependent Claim
38 words
The device of claim 22 wherein the columns are formed by dipping an array of hollow copper tubes in molten indium and, after cooling to solidify the indium within the tubes, removing the copper tubes by selective etching.
Claim 26
Dependent Claim
38 words
The device of claim 23 wherein the columns are formed by dipping an array of hollow copper tubes in molten solder and, after cooling to solidify the solder within the tubes, removing the copper tubes by selective etching.
Claim 27
Dependent Claim
123 words
A missile having a propulsion system, a guidance system and a payload wherein the guidance system includes a hybrid detector assembly for sensing infrared radiation, which assembly comprises: a detector module including a plurality of infrared sensors arranged in a predetermined array; a readout module including a plurality of contact pads arranged on a substrate in a predetermined array; and means including a plurality of extended columns of a conducting material respectively situated in positions between corresponding sensors of the detector module array and contact pads of the readout module array for supporting the two modules in interconnecting relationship while accommodating the assembly to thermal effects of temperature excursions between a cold operating temperature and standard room temperature which are encountered during use.
Claim 28
Dependent Claim
123 words
A missile having a propulsion system, a guidance system and a payload wherein the guidance system includes a hybrid detector assembly for sensing infrared radiation, which assembly comprises: a detector module including a plurality of infrared sensors arranged in a predetermined array; a readout module including a plurality of contact pads arranged on a substrate in a predetermined array; and means including a plurality of extended columns of a conducting material respectively situated in positions between corresponding sensors of the detector module array and contact pads of the readout module array for supporting the two modules in interconnecting relationship while accommodating the assembly to thermal effects of temperature excursions between a cold operating temperature and standard room temperature which are encountered during use.
Claim 29
Dependent Claim
13 words
The missile of claim 29 wherein the material of said columns is indium.
Claim 30
Dependent Claim
16 words
The missile of claim 29 wherein the material of said columns is an alloy of solder.
Claim 31
Dependent Claim
17 words
The missile of claim 29 wherein the columns are connected to the contact pads by indium bumps.
Claim 32
Dependent Claim
18 words
The missile of claim 32 wherein the columns are also connected to the infrared sensors by indium bumps.
Claim 33
Dependent Claim
21 words
The missile of claim 29 wherein the respective predetermined arrays contain corresponding arrangements of like pluralities of sensors and contact pads.
Claim 34
Dependent Claim
38 words
The missile of claim 30 wherein the columns are formed by dipping an array of hollow copper tubes in molten indium and, after cooling to solidify the indium within the tubes, removing the copper tubes by selective etching.
Claim 35
Dependent Claim
38 words
The missile of claim 31 wherein the columns are formed by dipping an array of hollow copper tubes in molten solder and, after cooling to solidify the solder within the tubes, removing the copper tubes by selective etching.
References Cited (Backward Citations)
No citation records indexed.
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