Microelectronic device package with integral waveguide transition
An example device includes: a multilayer build-up package substrate including trace conductor layers spaced from one another by dielectric material, and further including connection conductor layers coupling portions of the trace conductor layers through dielectric material, the multilayer build-up package substrate having a device side surface with one of the trace conductor layers and an opposing board side surface with one of the connection conductor layers; and a waveguide transition formed from the multilayer build-up package substrate, the waveguide transition having an input port formed from the connection conductor layer on the board side surface, and having at least two sub-transitions spaced laterally from one another, the at least two sub-transitions to couple a signal from the input port through the trace conductor layers and the connection conductor layers to a coplanar waveguide formed from the trace conductor layer on the device side surface.
1 . A method, comprising:
forming a multilayer build-up package substrate comprising conductors arranged as trace conductor layers spaced from one another by dielectric material and arranged as connection conductor layers coupling portions of the trace conductor layers through the dielectric material, the multilayer build-up package substrate having a trace conductor layer on a device side surface and having an opposing board side surface with a connection conductor layer on the board side surface;
forming a waveguide transition from the multilayer build-up package substrate, the waveguide transition having an input port formed from the connection conductor layer on the board side surface, and having at least two sub-transitions spaced laterally from one another and configured to couple a signal from the input port through the trace conductor layers and the connection conductor layers to a coplanar waveguide formed from the trace conductor layer on the device side surface; and
forming an antenna from the trace conductor layer on the device side surface, wherein the antenna is coupled to the coplanar waveguide.
2 . The method of claim 1 , wherein forming the multilayer build-up package substrate comprises:
patterning a first trace conductor layer over a carrier;
patterning a first connection conductor layer over the first trace conductor layer;
depositing the dielectric material over the first connection conductor layer and the first trace conductor layer;
grinding the dielectric material to expose the first connection conductor layer; and
patterning additional trace conductor layers, additional connection conductor layers, and depositing additional dielectric material over the additional trace conductor layers and over the additional connection conductor layers.
3 . The method of claim 1 , wherein forming the waveguide transition comprises:
forming a first sub-transition, a second sub-transition, and a third sub-transition, the first sub-transition coupling the input port at the board side surface to a lower stripline formed in a first one of the trace conductor layers, the second sub-transition spaced from the first sub-transition and coupling the lower stripline to an upper stripline formed in a second one of the trace conductor layers, and the third sub-transition spaced from the second sub-transition and coupling the upper stripline to the coplanar waveguide.
4 . The method of claim 1 , further comprising mounting a semiconductor die over the device side surface, the semiconductor die coupled to the coplanar waveguide by routing conductors in the trace conductor layer on the device side surface.
5 . The method of claim 4 , further comprising covering the semiconductor die and a portion of the multilayer build-up package substrate with mold compound or a lid to form a microelectronic device package.
6 . The method of claim 3 , wherein the upper stripline and the lower stripline are asymmetric striplines.
7 . A microelectronic device package, comprising:
a multilayer build-up package substrate comprising conductors arranged as trace conductor layers spaced from one another by dielectric material and arranged as connection conductor layers configured to couple portions of the trace conductor layers through the dielectric material, the multilayer build-up package substrate having a device side surface with a trace conductor layer on the device side surface and an opposing board side surface with a connection conductor layer on the board side surface;
a waveguide transition formed from the multilayer build-up package substrate, the waveguide transition having an input port formed from the connection conductor layer on the board side surface, and having at least two sub-transitions spaced laterally from one another and coupling a signal from the input port through the trace conductor layers to a coplanar waveguide formed from the trace conductor layer on the device side surface; and
mold compound covering the device side surface of the multilayer build-up package substrate, wherein the coplanar waveguide on the device side surface comprises a grounded coplanar waveguide.
8 . The microelectronic device package of claim 7 , wherein the at least two sub-transitions comprise:
a first sub-transition, a second sub-transition, and a third sub-transition, the first sub-transition coupling the input port at the board side surface to a lower stripline formed in a first one of the trace conductor layers, the second sub-transition spaced from the first sub-transition and coupling the lower stripline to an upper stripline formed in a second one of the trace conductor layers, and the third sub-transition spaced from the second sub-transition and coupling the upper stripline to the coplanar waveguide.
9 . The microelectronic device package of claim 8 , wherein the first sub-transition comprises:
the input port on the board side surface including a first via shaped portion; and
a first pad connection at one end of the lower stripline formed in the first one of the trace conductor layers overlying and contacting the first via shaped portion.
10 . The microelectronic device package of claim 9 , wherein the second sub-transition comprises:
a second via shaped portion formed in a second connection conductor layer overlying and in contact with one end of the lower stripline; and
a second pad connection formed in the second one of the trace conductor layers at one end of the upper stripline overlying and in contact with the second via shaped portion.
11 . The microelectronic device package of claim 10 , wherein the third sub-transition comprises:
a third via shaped portion formed in a third connection conductor layer overlying and in contact with one end of the upper stripline; and
a third pad connection at one end of the coplanar waveguide, the third pad connection overlying and in contact with the third via shaped portion.
12 . The microelectronic device package of claim 8 , wherein the upper stripline and the lower stripline are asymmetric striplines.
13 . The microelectronic device package of claim 8 , wherein the lower stripline has a length between the first sub-transition and the second sub-transition, and the length is proportional to a quantity (2n+1)*λ 1 /4, where n is an integer from 0 to infinity, and λ 1 is a wavelength of a frequency of a signal to be carried by the waveguide transition.
14 . The microelectronic device package of claim 13 , wherein the upper stripline has a length between the second sub-transition and the third sub-transition, and the length is proportional to a quantity (2n+1)*λ 2 /4, where n is an integer from 0 to infinity, and λ 2 is the wavelength of the frequency of the signal to be carried by the waveguide transition.
15 . The microelectronic device package of claim 14 , wherein λ 1 =λ 2 , and the frequency of the signal to be carried is between 30 GHz and 300 GHz.
16 . The microelectronic device package of claim 14 , wherein the frequency of the signal to be carried is between 140 GHz and 220 GHz.
17 . The microelectronic device package of claim 14 , wherein the frequency of the signal to be carried is about 196 GHz, and the length of the lower stripline and the length of the upper stripline are about 300 microns.
18 . The microelectronic device package of claim 7 , wherein the conductors comprise copper, gold, aluminum, silver, or an alloy thereof.
19 . The microelectronic device package of claim 7 , wherein the dielectric material comprises Ajinomoto build-up film (ABF), acrylonitrile butadiene styrene (ABS), acrylonitrile styrene acrylate (ASA), or resin epoxy.
20 . The microelectronic device package of claim 7 , further comprising:
a semiconductor die that is flip chip mounted to the device side surface of the multilayer build-up package substrate.
21 . The microelectronic device package of claim 20 , wherein the semiconductor die comprises a transceiver, a receiver, or a transmitter.
22 . The microelectronic device package of claim 7 , wherein the multilayer build-up package substrate has a substrate thickness of about 200 microns.
23 . The microelectronic device package of claim 7 , wherein the multilayer build-up package substrate has at least three trace conductor layers and at least three connection conductor layers.
24 . The microelectronic device package of claim 7 , further comprising at least one antenna formed on the device side surface of the multilayer build-up package substrate and coupled to the coplanar waveguide.
25 . A device, comprising:
a multilayer build-up package substrate comprising trace conductor layers spaced from one another by dielectric material, and further comprising connection conductor layers coupling portions of the trace conductor layers through the dielectric material, the multilayer build-up package substrate having a device side surface with one of the trace conductor layers on the device side surface and an opposing board side surface with one of the connection conductor layers on the board side surface; and
a waveguide transition formed from the multilayer build-up package substrate, the waveguide transition having an input port formed from the one of the connection conductor layers on the board side surface, and having at least two sub-transitions spaced laterally from one another, the at least two sub-transitions configured to couple a signal from the input port through the trace conductor layers and the connection conductor layers to a coplanar waveguide formed from the one of the trace conductor layers on the device side surface, wherein the coplanar waveguide is a grounded coplanar waveguide.
26 . The device of claim 25 , wherein the at least two sub-transitions comprise:
a first sub-transition, a second sub-transition, and a third sub-transition, the first sub-transition coupling the input port on the board side surface to a lower stripline formed in a first one of the trace conductor layers, the second sub-transition spaced from the first sub-transition and coupling the lower stripline to an upper stripline formed in a second one of the trace conductor layers, and the third sub-transition spaced from the second sub-transition and coupling the upper stripline to the coplanar waveguide.
27 . The device of claim 26 , wherein the first sub-transition comprises:
the input port on the board side surface comprising a first via shaped portion; and
a first pad connection at a first end of the lower stripline which is formed in the first one of the trace conductor layers overlying and contacting the first via shaped portion.
28 . The device of claim 26 , wherein the second sub-transition comprises:
a second via shaped portion formed in a second one of the connection conductor layers overlying and in contact with a second end of the lower stripline; and
a second pad connection formed in the second one of the trace conductor layers at a first end of the upper stripline, the second pad connection overlying and in contact with the second via shaped portion.
29 . The device of claim 26 , wherein the third sub-transition comprises:
a third via shaped portion formed in a third connection conductor layer overlying and in contact with a second end of the upper stripline; and
a third pad connection at an end of the coplanar waveguide, the third pad connection overlying and in contact with the third via shaped portion.
30 . The device of claim 25 , further comprising an antenna formed of the one of the trace conductor layers on the device side surface of the multilayer build-up package substrate and coupled to the coplanar waveguide.
31 . The device of claim 30 , wherein the antenna is configured to receive or transmit signals having a frequency between 30 GHz and 300 GHz.
32 . The device of claim 31 , wherein the signals have a frequency between 140 GHz and 220 GHz.