Micron has introduced unit shipments for its first DRAM manufactured on the 1α (1 alpha) node. This new reminiscence, which the corporate is constructing earlier than it has deployed EUV for manufacturing, will provide a bigger enchancment in bit density and a modest lower in energy consumption.
Initially, 1α shall be used for manufacturing DDR4 and LPDDR4. Over time, Micron expects to broaden the usage of the node to different merchandise. The corporate is claiming a bit density enchancment of 40 % over merchandise constructed utilizing the 1z manufacturing node. Energy consumption is alleged to have improved by “as much as” 20 %.
“The robust enchancment on 1-alpha bit density is pushed by mixture of course of expertise enchancment, in addition to very robust enchancment in array effectivity as a consequence of design enhancements,” mentioned Thy Tran, Micron vice chairman of DRAM course of integration. “Array effectivity alone gave us roughly 10 % of the design enchancment.”
We usually speak about manufacturing nodes in numerical phrases — 3nm, 5nm, 7nm, 20nm, and so forth. However these conventions consult with the way in which TSMC, Samsung, and Intel quantity their numerous nodes. As a result of all course of node names are arbitrary — there isn’t a common group or information that units a single metric for the business — totally different corporations can use totally different requirements. Reminiscence producers opted to maneuver away from straight numerical numbering after 20nm planar silicon and opted for metrics like 1X, 1Y, and 1Z. In accordance with Blocks and Files, 1X was roughly equal to 17-19nm manufacturing, 1Y was 14-16nm, and 1Z was 11-13nm. The identical website notes that 1Z manufacturing was 15 % of Micron’s DRAM bit manufacturing in Q3 2020.
What’s spectacular is that Micron is transferring to fabricate these new chips with out the usage of EUV. Excessive Ultraviolet Lithography is a producing technique that makes use of a lot smaller wavelengths of ultraviolet mild to etch wafers, versus the 193nm ArF lasers that energy DUV (Deep Ultraviolet Lithography). EUV has been making its manner into the business little by little for some years now, however it’s nonetheless not getting used a lot for DRAM manufacturing. Samsung makes use of EUV for its personal 1Z manufacturing, however it dedicates much less of its personal manufacturing in share phrases to 1Z than Micron does (6 % versus 15 %). Micron, nonetheless, is the smaller firm when it comes to market share.
Previously, Micron has implied that it would wait till 1β and even 1γ (1 beta or 1 gamma, respectively) to introduce EUV. The corporate has beforehand mentioned it will transfer to EUV solely when it was helpful, and it’s launched slides implying the shift date may very well be 2023 or later.
In accordance with Tran, Micron integrated new supplies, instruments, and “novel strategies” to enhance its multi-patterned alignment. The draw back of not utilizing EUV is that this will increase the necessity for multi-patterning. Multi-patterning permits 193nm lithography to focus on smaller function sizes than would in any other case be attainable, even by way of immersion lithography, however it additionally comes with tradeoffs when it comes to picture high quality.
Micron could also be slow-walking its EUV transition because of the restricted variety of EUV instruments being manufactured yearly, or as a result of its discovered alternate methods of bettering yields and efficiency. In the long term, each modern producer goes to maneuver to EUV, however Micron won’t make the shift earlier than 2022 or 2023 based mostly on its present roadmaps.
To present you an concept simply how lengthy the highway to EUV has been, right here’s an EETimes piece noting that Micron has joined “a non-public business group led by Intel, Superior Micro Units and Motorola… to develop next-generation lithography expertise that may substitute optical publicity instruments in wafer fabs.”
Publication date: Might 11, 2000.