# How to Combine Pressure and Motion Sensors on One Tiny Chip > This patent describes a method for building a single microchip that contains both a pressure sensor and a motion sensor, making devices smaller and more efficient. - **Patent:** US 8487387 - **Original title:** MEMS sensor device with multi-stimulus sensing - **Owner:** Freescale Semiconductor - **Granted:** 2013 - **Status:** Active - **Times cited:** 16 - **Field:** consumer_electronics, semiconductors, telecommunications, automotive ## What it does This device integrates two different types of tiny sensors, a first sensor (like a pressure sensor) and a second sensor (like an inertial sensor), onto a single chip. It uses a first substrate structure with a cavity and a second substrate structure where the sensors are built. The first sensor sits over the cavity, while the second sensor is positioned next to it, laterally spaced apart (Claim 1). A cap then encloses both sensors, often creating separate, isolated chambers for each (Claim 8). A clever part of the manufacturing is that key parts of both sensors, such as the pressure sensor's reference element and the inertial sensor's movable element, can be made at the same time from the same wafer material (Claim 4). For example, a smartphone could use this to measure both atmospheric pressure and how it's moving or tilting. ## What it does NOT cover - Does not cover a device where the first and second sensors are not laterally spaced apart on the second substrate structure. - Does not cover a device where the first sensor is not aligned with a cavity in the first substrate structure. - Does not cover a device where the cap does not physically isolate the first sensor's chamber from the second sensor's chamber. - Does not cover a device where the reference element of the pressure sensor and the movable element of the inertial sensor are not formed concurrently in the wafer substrate. - Does not cover a device where the first sensor is not a pressure sensor or the second sensor is not an inertial sensor. ## The clever bit The innovation lies in the specific fabrication process that allows critical components of different sensor types, like a pressure sensor's reference element and an inertial sensor's movable element, to be formed concurrently within the same wafer substrate. This shared manufacturing step simplifies production and improves alignment. ## Real-world examples 1. Smartphones (for altitude, motion tracking, and gaming) 2. Wearable fitness trackers (for activity monitoring and elevation changes) 3. Drones (for flight stability and altitude control) 4. Automotive sensors (for airbag deployment and electronic stability control) ## Why it matters Combining multiple sensors onto one chip, known as a multi-stimulus sensing device, is crucial for making electronics smaller, lighter, and more power-efficient. This integration reduces the number of separate components needed, which can lower manufacturing costs and simplify device design. This approach is fundamental for compact devices that need to understand both their environment (like air pressure) and their movement (like acceleration or tilt). ## Frequently asked questions ### What does How to Combine Pressure and Motion Sensors on One Tiny Chip cover? This patent describes a method for building a single microchip that contains both a pressure sensor and a motion sensor, making devices smaller and more efficient. ### Who owns patent US 8487387? Freescale Semiconductor owns this patent, granted in 2013. ### When does this patent expire? This patent is expected to expire on June 18, 2032, when the invention enters the public domain. ### What is patent US 8487387 cited by? This patent has been cited by 16 later patents that build on its ideas. ### What problem does this patent solve? Combining multiple sensors onto one chip, known as a multi-stimulus sensing device, is crucial for making electronics smaller, lighter, and more power-efficient. This integration reduces the number of separate components needed, which can lower manufacturing costs and simplify device design. This approach is fundamental for compact devices that need to understand both their environment (like air pressure) and their movement (like acceleration or tilt). ### What does this patent NOT cover? Does not cover a device where the first and second sensors are not laterally spaced apart on the second substrate structure. **Full plain-English explainer:** https://patentbrief.org/patent/us/8487387/mems-sensor-device-with-multi-stimulus-sensing **Original patent:** https://patents.google.com/patent/US8487387 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [Combining Sealed and Exposed Sensors on One Microchip](https://patentbrief.org/patent/us/8387464/laterally-integrated-mems-sensor-device-with-multi-stimulus-sensing) — This patent describes a microchip design that integrates multiple tiny sensors on the same side, where one sensor is exposed to the outside world through a backside hole while others remain protected by a sealed cap. - [How to Build a Tiny Pressure Sensor Inside a Silicon Chip](https://patentbrief.org/patent/us/10578505/process-for-manufacturing-a-mems-pressure-sensor-and-corresponding-mems-pressure) — This patent describes a method for building a tiny pressure sensor, called a MEMS sensor, directly inside a silicon chip, where a flexible membrane and a plate form a capacitor that changes with pressure. - [How a Tiny Sensor Uses an Extra Weight to Detect Motion](https://patentbrief.org/patent/us/20110120221/mems-sensor-method-of-manufacturing-thereof-and-electronic-apparatus) — This patent describes a miniature sensor that detects movement or force by measuring changes in electrical signals between tiny plates, featuring a clever extra weight to make it more sensitive. - [How a MEMS Sensor Uses a Reference to Improve Z-Axis Accuracy](https://patentbrief.org/patent/us/8146425/mems-sensor-with-movable-z-axis-sensing-element) — This patent describes a tiny sensor that measures up-and-down motion more accurately by including a special surrounding structure that helps cancel out environmental interference. - [Improving MEMS Sensor Accuracy with a Co-located Reference Structure](https://patentbrief.org/patent/us/8939029/mems-sensor-with-movable-z-axis-sensing-element-8939029) — This patent describes a tiny sensor (MEMS) that measures motion, especially up-and-down (z-axis), by including a special stable reference part electrically connected to the moving part, which helps cancel out environmental noise and makes measurements much more accurate.