Making multilayer 3D capacitors using arrays of upstanding rods or ridges

• US 9,865,675 B2
• Filed: 07/12/2016
• Issued: 01/09/2018
• Est. Priority Date: 06/13/2014
• Status: Active Grant

• Current Assignee: Invensas Corporation
• Original Assignee: Invensas Corporation
• Inventors: Wang, Liang, Katkar, Rajesh, Shen, Hong, Uzoh, Cyprian Emeka
• Primary Examiner(s): JUNGE, BRYAN R.
• Application Number:
  US15/207,837
• Publication Number:
  US 20160322456A1
• Time in Patent Office: 546 Days
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/17181 On opposite sides of the body
• CPC Class Codes: H01L 28/65 comprising a noble metal or a noble metal oxide, e.g. platinum (Pt), ruthenium (Ru), ruthenium dioxide (RuO2), iridium (Ir), iridium dioxide (IrO2)
• CPC Class Codes: H01L 28/90 having vertical extensions
• CPC Class Codes: H01L 28/92 made by patterning layers, e.g. by etching conductive layers
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15184 in different layers of the multilayer substrate
• CPC Class Codes: H01L 2924/15192 Resurf arrangement of the internal vias
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/16151 Cap comprising an aperture, e.g. for pressure control, encapsulation
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/16251 Connecting to an item not being a semiconductor or solid-state body, e.g. cap-to-substrate
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate

Abstract

In one embodiment, a method for making a 3D Metal-Insulator-Metal (MIM) capacitor includes providing a substrate having a surface, forming an array of upstanding rods or ridges on the surface, depositing a first layer of an electroconductor on the surface and the array of rods or ridges, coating the first electroconductive layer with a layer of a dielectric, and depositing a second layer of an electroconductor on the dielectric layer. In some embodiments, the array of rods or ridges can be made of a photoresist material, and in others, can comprise bonded wires.

Claims

1. A method for making a capacitor, the method comprising:

providing a substrate having a surface;

forming at least one upstanding rod or ridge on the surface;

depositing a first layer of an electroconductor on the surface and on the at least one rod or ridge;

coating the first electroconductive layer with a layer of a dielectric; and

depositing a second layer of an electroconductor on the dielectric layer;

wherein the forming comprises;

coating the surface of the substrate with a photoresist;

patterning the photoresist to define the at least one upstanding rod or ridge therein; and

stripping the photoresist from the surface of the substrate so as to leave the at least one rod or ridge upstanding thereon.

2. The method of claim 1, wherein the forming comprises forming an array of upstanding rods or ridges.

3. The method of claim 1, wherein the depositing of the first layer or the depositing of the second layer comprises at least one of atomic layer deposition (ALD), chemical vapor deposition (CVD), and sputtering.

4. The method of claim 1, wherein the coating of the first electroconductive layer with the layer of a dielectric comprises depositing a vapor phase of a polymer or forming a self-assembled monolayer (SAM).

5. The method of claim 1, wherein the substrate includes a cavity, the surface of the substrate comprises a floor of the cavity, and the at least one upstanding rod or ridge is disposed at least partially within the cavity.

6. A capacitor, comprising:

a substrate;

an array of upstanding rods or ridges disposed on a surface of the substrate; and

a sandwich disposed over the surface of the substrate and the array of upstanding rods or ridges, the sandwich comprising at least one layer of a dielectric sandwiched between at least two electroconductive layers;

wherein at least one of the rods or ridges of the array comprises a photoresist.

7. The capacitor of claim 6, wherein the substrate comprises at least one of a semiconductor, glass, ceramic, or a polymer.

8. The capacitor of claim 6, wherein the photoresist comprises Benzocyclobutene (BCB), polyimide, spun-on glass, or SU-8.

9. The capacitor of claim 6, wherein the at least one dielectric layer comprises Parylene or a self-assembled monolayer (SAM) comprising at least one thiol group.

10. The capacitor of claim 9, wherein the SAM comprises an alkanethiol.

11. The capacitor of claim 6, wherein the at least one dielectric layer comprises hafnium oxide (HfO₂), tantalum pentoxide (Ta₂O₅), zirconium dioxide (ZrO₂), yttrium oxide (Y₂O₃), lanthanum oxide (La₂O₃), titanium dioxide (TiO₂), strontium titanate (SrTiO₃), or an alkanethiol having a thiol group on both ends.

12. The capacitor of claim 6, wherein at least one of the at least two electroconductive layers comprises Tantalum (Ta), Copper (Cu), Titanium (Ti), Titanium Nitride (TiN), Silver (Ag), Gold (Au), or Palladium (Pd).

13. A capacitor, comprising:

a substrate;

an array of upstanding rods or ridges disposed on a surface of the substrate; and

a sandwich disposed over the surface of the substrate and the array of upstanding rods or ridges, the sandwich comprising at least one layer of a dielectric sandwiched between at least two electroconductive layers;

wherein the at least one dielectric layer comprises an alkanethiol having a thiol group on both ends;

wherein the alkanethiol comprises Dithiothreitol (C4H10S2), 1,2-Ethanedithiol (C2H4(SH)2), Biphenyl-4,4′

-dithiol (HSC6H4SH), or 1,4-Benzenedimethanethiol (C6H4(CH2SH)2).