Guiding, Localizing and IMaging confined GHz acoustic waves in GaN Elastic waveguides and Resonators for monolithically integrated RF front-ends

用于单片集成射频前端的 GaN 弹性波导和谐振器中的有限 GHz 声波的引导、定位和成像

基本信息

批准号：
EP/V005286/1
负责人：
Krishna Coimbatore Balram
金额：
$ 122.66万
依托单位：
University of Bristol
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2021
资助国家：
英国
起止时间：
2021 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FV005286%2F1
关键词：
Guiding Localizing IMaging confined GHz

项目摘要

As smartphones become the dominant mechanism for information transfer and processing in modern society, our expectations on what we hope to achieve with them also increases proportionally. In particular, the smart phone has become our portal to the internet, replaced our television, radio and music devices, and also serves as our credit card and personal guide (GPS). We also expect our mobile phones to work seamlessly as we travel across international borders. All of this is enabled by the separation of the various functions into different wireless (RF) frequency bands, and the development of sophisticated analog and digital circuitry, that enables the phone to simultaneously carry out these communications. As we move towards 5G and other technologies that increase the data throughput available, these channels must increase. While on the digital signal processing side, the steady advance of Moore's law and microelectronic integration has enabled silicon technology to keep up with the demand, this is not the case for the RF front-end circuitry, which is primarily analog. The RF front-end circuit, receives the signal from the antenna and separates it into different channels (based on RF filters), amplifies it with a low noise amplifier (LNA) and then hands it over to the DSP for baseband signal processing. Currently, RF filters and LNAs are primarily discrete devices that are co-packaged together. While this hybrid approach has certain advantages (mainly the choice of piezoelectric materials for the filter), as demand for filters continuously rises, it is known that a co-packaging approach will not scale. The main reason is that the available smartphone footprint (in terms of chip area) for the RF front-end has remained roughly the same across generations, while the filtering demand has continuously increased. As the microelectronics industry has repeatedly taught us, monolithic integration is the only long-term solution to address these problems. In this project, we will demonstrate that gallium nitride (GaN) is the ideal platform for achieving monolithic integration by exploiting a key advantage that GaN provides over traditional solutions: acoustic waveguiding. GaN allows us to guide high-frequency sound on the surface of chip with low acoustic attenuation. By routing sound in nanoscale waveguides and localising it in micron-scale resonators, one can re-design RF system components from the ground up realizing a massive reduction in component footprint, which is key to enabling monolithic integration. By applying ideas from integrated photonics to high-frequency acoustics, we hope to realize for RF systems the same benefits (in terms of size, weight and performance) that silicon photonics has achieved for optical telecommunication systems. We will show that high quality RF passive devices (in particular, piezoelectric resonators and filters) can be built on the same GaN substrate as the active transistor devices. We will implement a process flow and design the associated process development kit to implement these ideas in commercial GaN RF foundries (for ex: the Newport wafer fab) in collaboration with our project partners.

随着智能手机成为现代社会信息传输和处理的主导机制，我们对智能手机实现目标的期望也相应增加。特别是，智能手机已成为我们的互联网门户，取代了我们的电视、收音机和音乐设备，并且还充当我们的信用卡和个人指南（GPS）。我们还希望我们的手机在跨越国际边界时能够无缝工作。所有这一切都是通过将各种功能分离到不同的无线（RF）频段以及复杂的模拟和数字电路的开发来实现的，这使得手机能够同时进行这些通信。随着我们向 5G 和其他增加可用数据吞吐量的技术迈进，这些通道必须增加。虽然在数字信号处理方面，摩尔定律和微电子集成的稳步发展使得硅技术能够跟上需求，但对于主要是模拟的射频前端电路来说，情况并非如此。射频前端电路，接收来自天线的信号并分离到不同的通道（基于射频滤波器），通过低噪声放大器（LNA）放大，然后交给DSP进行基带信号处理。目前，射频滤波器和 LNA 主要是共同封装在一起的分立器件。虽然这种混合方法具有一定的优势（主要是滤波器压电材料的选择），但随着对滤波器的需求不断上升，众所周知，联合封装方法将无法扩展。主要原因是，射频前端可用的智能手机占地面积（就芯片面积而言）在各代之间保持大致相同，而滤波需求却不断增加。正如微电子行业反复教导我们的那样，单片集成是解决这些问题的唯一长期解决方案。在该项目中，我们将利用 GaN 相对于传统解决方案的关键优势：声波导，证明氮化镓 (GaN) 是实现单片集成的理想平台。 GaN 使我们能够以较低的声学衰减在芯片表面引导高频声音。通过在纳米级波导中路由声音并将其定位在微米级谐振器中，人们可以从头开始重新设计射频系统组件，从而大幅减少组件占用空间，这是实现单片集成的关键。通过将集成光子学的思想应用于高频声学，我们希望为射频系统实现硅光子学为光通信系统带来的相同优势（在尺寸、重量和性能方面）。我们将展示高质量射频无源器件（特别是压电谐振器和滤波器）可以构建在与有源晶体管器件相同的 GaN 衬底上。我们将与我们的项目合作伙伴合作实施工艺流程并设计相关的工艺开发套件，以在商业 GaN RF 代工厂（例如：纽波特晶圆厂）中实施这些想法。