Futuristic city made of microchips

Future Chips: 3D Tech Could Revolutionize Electronics

Jordan Keane in Tech & Innovation September 2025 • 4 min read.

"Scientists are making NEM memory switches smaller with a smart new process, so electronics could be even faster and more efficient."

For years, electronics engineers have been working on making computer chips smaller and more powerful. One exciting area is called CMOS-NEM hybrid circuits. These circuits combine traditional semiconductor tech (CMOS) with tiny mechanical switches (NEMs). The goal is to create electronics that use less power, perform better, cost less to make, and pack more into a smaller space.

One big challenge is how to precisely make the NEM memory switches, especially when stacking them in three dimensions (3D). A key step involves carefully removing material to create the tiny spaces where the switches can move. This process, called "release," needs to be done without damaging the rest of the chip.

Now, researchers are developing a new way to protect these delicate NEM memory switches during manufacturing. By using special coatings, they can build these switches in any layer of a 3D chip. This opens the door for more efficient designs and smaller, more powerful devices.

A Smarter Way to Build 3D Chips

The problem with the standard method is that it can damage the chip's layers while creating the air gaps for the NEM switches. The old method uses a harsh chemical (vapor HF) to remove material, but it’s like using a sledgehammer where you need a tiny brush. This can cause the chip's layers to collapse, making it hard to place the switches exactly where they’re needed. This creates a 'dead zone' around the switches, wasting space and making design difficult.

The new method involves a clever way to encapsulate the NEM memory switches using a material called alumina (Al2O3). This material acts like a shield, protecting the underlying layers of the chip during the release process. Think of it as building a tiny fortress around each switch.

Protective Layers: Alumina layers safeguard the chip during the etching process.
Precise Cavities: The method allows for creating exact spaces for the switches to move.
No Dead Zones: Switches can be placed anywhere on the chip, maximizing space.
CMOS Friendly: The process works well with standard chip-making techniques.

This encapsulation method works by depositing layers of alumina to protect the structure. Then, the areas around the NEM switches are carefully etched away. Because the alumina shields the rest of the chip, the etching only affects the intended areas. This precision means engineers can put NEM switches in any metal layer, making the chip design much more flexible and efficient. Tests show that this method is effective, paving the way for more complex 3D chip designs.

What This Means for the Future

This new encapsulation method could be a game-changer for building 3D chips. By protecting the delicate NEM memory switches, engineers can create more compact and efficient designs. This could lead to smaller, faster, and more energy-efficient electronic devices. The ability to place switches anywhere on the chip opens up exciting possibilities for future innovations in electronics.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.3390/mi9070317, Alternate LINK

Title: Encapsulation Of Nem Memory Switches For Monolithic-Three-Dimensional (M3D) Cmos–Nem Hybrid Circuits

Subject: Electrical and Electronic Engineering

Journal: Micromachines

Publisher: MDPI AG

Authors: Hyun Jo, Woo Choi

Published: 2018-06-23

Everything You Need To Know

What are CMOS-NEM hybrid circuits and what advantages do they offer in electronics?

CMOS-NEM hybrid circuits combine traditional semiconductor technology (CMOS) with Nano-Electro-Mechanical (NEM) memory switches. The aim is to create electronics that consume less power, perform better, cost less to manufacture, and have a smaller footprint. This integration seeks to leverage the strengths of both technologies for enhanced performance and efficiency in electronic devices.

What are the limitations of the standard method of creating air gaps for Nano-Electro-Mechanical (NEM) memory switches in chips?

The traditional method of creating air gaps for NEM memory switches involves using a harsh chemical (vapor HF) to remove material. This can damage the chip's layers, causing them to collapse and creating 'dead zones' around the switches. These dead zones waste space and limit design flexibility, hindering the efficient placement of switches.

How does the new method using alumina (Al2O3) improve the manufacturing of NEM memory switches in 3D chips?

The new method encapsulates NEM memory switches using alumina (Al2O3). Alumina acts as a protective shield during the etching process, preventing damage to the underlying layers. This allows for the creation of precise cavities for the switches and eliminates dead zones, enabling switches to be placed anywhere on the chip. The alumina layers safeguard the chip during etching, allowing for precise cavities without dead zones and ensuring compatibility with CMOS techniques.

Can you explain the process of the alumina encapsulation method for protecting NEM memory switches during chip manufacturing?

This alumina encapsulation method involves depositing layers of alumina to protect the structure. The areas around the NEM memory switches are then carefully etched away. The alumina shields the rest of the chip, ensuring that the etching only affects the intended areas. This precision allows engineers to place NEM switches in any metal layer, resulting in more flexible and efficient chip designs.

What are the potential implications of the new alumina encapsulation method for the future of 3D chip design and electronic devices?

The alumina encapsulation method could enable the creation of more compact and efficient 3D chips. By protecting the NEM memory switches, engineers can design smaller, faster, and more energy-efficient electronic devices. This opens up new possibilities for future innovations in electronics, such as placing switches anywhere on the chip and maximizing space utilization. This innovation paves the way for more complex 3D chip designs and potential advancements in electronic device performance.