集微访谈 | Dale Gai：传统工艺28nm供不应求；台积电新厂首选40nm和28nm节点

集微网消息，在往期的集微访谈栏目中，爱集微有幸采访了知名半导体分析机构Counterpoint的中国台湾研究主管Dale Gai。他在半导体和组件研究等领域拥有丰富的经验。集微访谈就关于28nm制程以及台积电日本新厂等方面提出了一系列问题，并收到了十分有启发的答复。

问：您能否分析一下，28nm工艺、DDIC、PMIC或其他一些功率器件的主要领域是哪些？

答：28/22nm是一个大节点，拥有各种技术平台，如LP、HPC、HPC plus、RF-SOI，适用于所有应用，以及特殊工艺，如HV（高压）、eFlash（嵌入式存储器）。因此，在这个矩阵中，不同的代工供应商提供他们的重点/利基服务。 在应用方面，根据我们的研究，CIS/ISP、DDIC、WiFi和MCU（+eFlash）是前四大应用，占2023年行业总收入的19%/18%/15%/10%。PMIC/ analog 此时不需要这个高级节点。

问：台积电将在日本熊本成立子公司Japan Advanced Semiconductor Manufacturing, Inc. (“JASM”)，目标是40nm-28nm制程节点，JASM为何选择这个制程节点？

答：40/28nm节点涵盖了日本最重要的两个半工业领域：传感器（尤其是CMOS传感器）和 MCU（尤其是汽车），这就是为什么索尼和瑞萨是使用该晶圆厂的前2大客户。

问：美国的芯片法案建立了一个激励计划，以重建和维持美国在整个半导体供应链中的领导地位。28纳米或更老一代被定义为“传统半导体”，这是对中国技术限制的一大门槛。在您看来，这个定义和限制将如何影响28nm平台（设备、IP、EDA）的生态系统？

答：正如我们所提到的，28/22nm是代工厂的一个重要技术节点，因为该工艺开始采用更先进的光刻工艺（如双图案），这需要ASML的浸入式DUV模型。根据最新的BIS，AMSL的NXT1980i仍然允许在中国销售，支持基本的28nm工艺，但更高一级NXT20平台被禁止，因为它将限制中国晶圆代工向22nm及以上的迁移。

问：一般来说，28nm的产能相对于尖端节点（7nm或以下）来说是相对稳定的。同时，您认为全球芯片短缺（2021-2022）是否催化了28nm的产能扩张？另外，根据您的观察，目前成熟节点（28nm、40nm等）是处于供过于求还是供不应求的周期？

答：实际上28/22nm是所有成熟技术中最积极的容量增加节点，来自除三星代工之外的所有领先供应商。未来3年（从2024年开始，因为今年已经推迟了一些），28nm产能增加的CAGR将达到10%。正如我们所说，这个节点为各种终端设备提供了许多不同的产品，地缘（美中）和全球脱钩问题使总需求膨胀。因此，如果我们只计算晶圆供需，就会出现名义上的供过于求。

问：荷兰政府可能会限制ASML的DUV设备出口到中国，这对28nmn制程节点的供需会有什么影响？

答：正如我们在上面强调的那样，任何在NXT:2000及更高版本上使用ASML的DUV工具的过程都将被禁止。基本28纳米(LP)和特殊HV不会受到影响，但某些采用双图案化的28/22纳米逻辑部件会受到影响。

问：广义上讲，28nm如何应用于汽车芯片？

答：2023-2024年约10-15%，包括MCU、WiFi/IoT模块、RF、CIS和显示驱动芯片(DDIC)。

以下为采访原文（英文）：

Q: Could you analyse, Which areas are the main segments regarding 28nm process, DDIC, PMIC or some other power devices? 

A: 28/22nm is a big node with various technology platforms, such as LP, HPC, HPC plus, RF-SOI, for all applications, and specialty processes such as HV (high votage), eFlash (embedded memory). So in this matrix different foundry vendors offer their focus/niche services. Regarding applicaitons, based on our research, CIS/ISP, DDIC, WiFi, and MCU (+eFlash) are the top four applications, accouting for 19%/18%/15%/10% of total indsutry revenue in 2023. PMIC/analog do not need this advanced node at this point. 

Q: TSMC will establish a subsidiary, Japan Advanced Semiconductor Manufacturing, Inc. (“JASM”), in Kumamoto, Japan, which is targeting 40nm-28nm process node, why does JASM choose this process node?

A: 40/28nm node covers the most important two semi industry segments in Japan: sensor (esp CMOS sensor) and MCU (esp automotive), and that's why Sony and Renasas are the top 2 clients using this fab. 

Q: The CHIPS Act of U.S established an incentives program to reestablish and sustain U.S. leadership across the semiconductor supply chain.28-nanometer generation or older has been defined as the “Legacy semiconductor”, which is a big threshold of technological restriction to China. According to you, how the ecosystem of 28nm platforms(equipments, IP, EDA) would be affected by this definition and restriction?

A: As we mentioned, 28/22nm is a big technology node for foundry, as the process starts to engage more advanced litho process (like double-patterning) which is in need of ASML's immerssion DUV models. Per the latest BIS, AMSL's NXT1980i is still allowed to sold in China, supporting the basic 28nm process, but the next-grade NXT20xx is banned, as it will constrain the migration of 22nm and above for China foundry. 

Q: Generally speaking, the capacity of 28nm is relatively stable, comparing to cutting edge nodes(7nm or below). while, do you believe the global chip shortage (2021-2022) catalyzed 28nm’s capacity expansion? Besides, based on your observation, currently, are mature nodes(28nm, 40nm etc.) under the oversupply or undersupply cycle?

A: Actually 28/22nm is the most aggresive capacity increase node acorss all matured technologies, from all leading vendors except Samsung/IFS. The CAGR of capacity adds in 28nm will be 10% in the next 3 years (from 2024 as some has been postponed this year). As we said, this node offers many different products for all kinds of end devices, and the geo (US-China) and global decoupling issues inflate the total demand. Thus, a nominal oversupply will happen if we just count wafer supply/demand. 

Q: The Dutch government may restrict the export of ASML's DUV equipment to China, what impact will this have on the supply and demand for the 28nmn process node?

A: As we highlight above, any process engages with ASML's DUV tools at NXT:2000 and above will be banned. Basic 28nm (LP) and specialty HV will not be impacted, but some logic parts at 28/22nm with double-patterning will be effected. 

Q: Broadly speaking, how is the 28nm applied to automotive chips?

A: About 10-15% in 2023-2024, including MCUs, WiFi/IoT module, RF, CIS and display (DDIC).