Apple reveals the creation & use of Nanotwin Copper Components to keep iDevices from overheating while extending battery life
Each year Apple fans want, if not expect, iDevices like iPhones, iPads and Apple Watches to be thinner and AirPods to be smaller. In order to do that smartly so as to not generate too much heat within the devices that could harm internal components, Apple has developed a method of using nanotwin copper components. Whether it's being used today or something that will be used in the future is unknown at this time. Using nanotwin copper components will result in compounding efficiencies that allow for reduced charging times, increased battery life, and other advantages.
Apple's patent background helps non-engineers understand the need and benefits of using this new process involving nanotwin copper components.
Apple notes that recent technological advances have enabled manufactures to include a large number of operational components, such as processors, antennas, displays, cameras, haptic feedback components, and batteries, in a relatively small internal volume defined by a housing or enclosure of a portable electronic device.
Due to the drive for thinner and smaller electronic devices, the internal volume of the device can be relatively small and can include a number of operational components in close proximity with one another. Further, the increasing performance levels of these components can require greater amounts of power to be delivered to the components in shorter amounts of time.
In use, the levels of electrical resistance and thermal conductivity in these operational components, and in circuits including these operational components, can result in the generation of heat or thermal energy that can cause the components themselves, as well as any other components nearby, to experience elevated operating temperatures.
These elevated operating temperatures can reduce device performance and can result in undesirable levels of stress on the device components. Accordingly, it can be desirable to reduce the electrical resistance and increase the thermal conductivity of operational components and circuits to allow for high levels of current to flow without producing undesirably high levels of heat or thermal hotspots.
Traditionally, metal alloys have been included in the materials forming these operational components and circuits that seek to reduce the electrical resistance of the materials. This approach can result in materials that have a relatively low resistance, but that also have a relatively low mechanical strength. Similarly, techniques to increase the mechanical properties of the materials of operational components and circuits can result in materials that have a relatively high electrical resistance.
Accordingly, it can be desirable to provide materials that have desired levels of electrical resistance and thermal conductivity, while also achieving desired levels of mechanical properties. And this is what Apple's invention sets out to accomplish.
Apple's invention takes on a method of forming a component that can include depositing a metallic material including crystal grains onto a carrier to a thickness of greater than 50 microns, with at least 90% of the crystal grains including nanotwin boundaries.
The nanotwin boundaries can be spaced apart from one another within the crystal grains by between about 50 microns and about 200 microns. The metallic material can include copper, silver, and/or alloys thereof.
The improved material properties, such as strength, hardness, electrical conductivity, and thermal conductivity of nanotwinned metallic materials relative to non-nanotwinned metallic materials and alloys can also allow for new component and device designs that take advantage of these improved material properties.
For example, components that conduct or transmit electrical power can have smaller dimensions because the mechanical strength of the metallic portions of these components may no longer constrain the design. Further, the high levels of electrical conductivity provided by nanotwinned metallic materials can allow for highly efficient power or signal transmission, even though these components having reduced dimensions.
The use of highly conductive nanotwinned metallic materials in multiple components or locations along an electronic device's charging pathway, for example, can result in compounding efficiencies that allow for reduced charging times, increased battery life, and other advantages.
Apple's patent FIGS. 11A, 15A, 18A, 19B and 20A represent Apple's iPhone, AirPods, Apple Watch, iPad with Smart Keyboard and a device battery that could use nanotwin components; FIG. 1 shows a plot of thermal and electrical conductivity versus yield strength and hardness for various metallic materials; FIG. 2A shows a scanning electron micrograph of a cross-section of a nanotwinned metallic material; and FIG. 6B shows a process flow diagram for a process of forming a nanotwinned metallic material.
Apple's patent application 20210159477 is a highly technical patent that engineers and developers may enjoy diving into here for more details.