Avoid Tape-Out Failure with This HiSilicon Checklist

A successful tape-out is not a matter of luck. You achieve it through a rigorous, systematic verification process. This guide provides the definitive checklist for navigating the final HiSilicon sign-off stages. Following this design review checklist minimizes catastrophic bugs in your chip design. You can save millions in mask costs and avoid months of schedule delays. This process transforms your design into a successful semiconductor product.

The semiconductor industry faces a tough challenge. Recent studies show only 14% of projects achieve first-silicon success, a two-decade low. Your design and this checklist can beat those odds.

Use this tool to build tape-out confidence and achieve first-pass silicon success for your next semiconductor chip.

Key Takeaways

• Use a certified Process Design Kit (PDK) and approved IP blocks. This prevents major problems early in your chip design.
• Run Design Rule Checks (DRC) and Layout Versus Schematic (LVS) often. This finds and fixes manufacturing errors before they become big issues.
• Check your chip's power grid and thermal performance. This ensures your chip works well and does not overheat.
• Verify your chip's timing and signal quality. This makes sure your chip runs at the right speed and sends data correctly.
• Perform full-chip simulations and Design for Test (DFT) checks. This confirms your chip works as planned and can be tested easily after it is made.

FOUNDATIONAL DESIGN REVIEW CHECKLIST:

Your journey to a successful tape-out begins here. These initial checks are non-negotiable. Many tape-out failures happen because teams use outdated technology or have poor planning. This foundational design review checklist helps you build your chip on a solid, verified base. Following this checklist prevents common errors early in the process. A strong foundation is essential for a successful semiconductor design.

Note: Using an uncertified Process Design Kit (PDK) or an unproven Intellectual Property (IP) block is a critical mistake. It introduces unknown risks that can derail your entire project.

PDK AND IP VERSION VERIFICATION:

You must confirm you are using the correct PDK version for your target process. Your design relies on this kit for manufacturing rules. Next, verify every IP block in your design. This includes processors, interfaces, and other third-party components. You need to check that each IP version is approved for your specific semiconductor project. Inadequate validation of IPs leads to costly bugs and rework.

EDA TOOL AND FLOW VALIDATION:

Your Electronic Design Automation (EDA) tools build the chip. You must ensure every tool in your flow is the correct version certified by HiSilicon. Inconsistent tool versions create subtle errors that are difficult to find later. Your validation should confirm:

• All tools are on the approved list.
• The entire design flow runs without errors.
• Scripts and automation are compatible with the tool versions.

LIBRARY AND CELL CONSISTENCY:

The final step in this design review checklist is to verify all your libraries. Your chip design uses these libraries for basic building blocks. You must check all standard cells, memory compilers, and I/O libraries. Confirm they match HiSilicon's approved list for the chosen semiconductor process. This check guarantees that the physical elements of your chip match the logical design, ensuring predictable performance and manufacturability.

PHYSICAL VERIFICATION SIGN-OFF:

You have now reached the core of physical sign-off. This stage ensures your logical design can actually be manufactured. Think of this as the final inspection before your design is sent to the foundry. Each check must be "clean" with zero errors. A formal review, often documented in a "Tape-out Review Form," confirms that every manufacturing rule is met. Your goal is to get a perfect score.

A formal sign-off review for a HiSilicon tape-out typically verifies:

• Connectivity Checks: You confirm all required connections are present and have no open circuits.
• Short Circuit Checks: You identify and fix any shorted nodes, especially between power and ground.
• Layout Versus Schematic (LVS): You compare the physical layout to the original schematic to ensure a perfect match.
• Electro-Static Discharge (ESD): You verify that the design has adequate protection against ESD events.

DESIGN RULE CHECK (DRC):

Design Rule Check (DRC) is your first and most critical manufacturing test. It verifies that your layout meets the foundry's specific geometric constraints for the chosen semiconductor process. These rules govern spacing, width, and other physical properties. A clean DRC report is non-negotiable.

To avoid major problems, you should run DRC early and often. Do not wait until the final days before tape-out. Best practices for a clean design include:

• Run DRC after placing the power grid to find and fix via issues early.
• Perform another check after placing all cells to verify alignment and spacing.
• Execute a full DRC run as soon as signal routing is complete to vet the entire design.

This iterative approach helps you catch errors when they are easier to fix, ensuring a smoother final sign-off.

LAYOUT VERSUS SCHEMATIC (LVS):

Layout Versus Schematic (LVS) confirms that your physical layout is electrically identical to your original schematic design. It is the ultimate fact-check for your implementation work. LVS ensures that the circuit you designed is the same one you are about to build. A clean LVS report means your layout has the correct components and connections.

Common LVS errors often involve shorts or opens.

• Shorts occur when two different nets touch. Your LVS report will show a lower net count in the layout than in the source schematic.
• Opens happen when parts of the same net are not connected. This can lead to floating gates and chip failure. Your LVS report will show a higher net count in the layout.

You may also encounter device mismatches, such as when an IP's GDS file does not match its netlist. Running LVS on individual IPs before integrating them into the top-level design can prevent these surprises.

ANTENNA AND ERC CHECKS:

Antenna checks protect your design from damage during the manufacturing process. Long metal interconnects can accumulate charge during plasma etching, potentially destroying transistor gates. The antenna check identifies and flags these vulnerable nets so you can add protective diodes or break up long wires.

Electrical Rule Checks (ERC) look for other electrical problems not covered by DRC or LVS. These include:

• Floating n-wells or substrates.
• Missing well taps.
• Incorrect power and ground connections.

Forgetting to add filler cells can cause well discontinuity, leading to power opens that ERC can detect. These checks are vital for the electrical robustness of your semiconductor design.

DENSITY AND FILL VALIDATION:

Foundries require a specific range of metal density across the chip. This ensures uniformity during chemical-mechanical polishing (CMP), a key manufacturing step. If density is too low or too high in an area, it can lead to an uneven surface and yield loss.

You must run density checks to identify regions that violate these rules. To fix low-density areas, you will add non-functional metal shapes, known as "metal fill." Your place-and-route tool can do this automatically, but you must verify that the final filled design meets all density requirements without creating new DRC or timing violations.

OFF-GRID PIN CHECK:

This is a simple but essential check. It verifies that all pins on your blocks and top-level design are placed on the correct manufacturing grid. If a pin is off-grid, automated tools at the foundry may not be able to connect to it. This small error can make an entire block or even the whole chip unusable. You must run this check to ensure every connection point is perfectly aligned.

CHIP FINISHING AND SEAL RING:

Chip finishing is the final step in creating your GDSII file. This involves adding the seal ring, scribe lines, and any required text or logos. The seal ring is a metal structure around the perimeter of the die. It protects the internal circuitry from moisture and contaminants that can enter from the edge of the die after it is cut from the wafer. You must ensure the seal ring is properly constructed and connected to power or ground according to HiSilicon's guidelines for your design.

PERFORMANCE AND POWER SIGN-OFF:

After confirming your design is manufacturable, you must verify it performs as expected. This performance and power sign-off stage ensures your chip meets its speed, power, and reliability targets. A design that is physically correct but fails to meet performance goals is still a failure. You must rigorously analyze every aspect of your chip's dynamic behavior.

STATIC TIMING ANALYSIS (STA):

Static Timing Analysis (STA) is the cornerstone of performance verification. You use it to confirm your design can operate at its target frequency across all conditions. STA checks for timing violations without running full simulations. It calculates signal propagation delays through every path in your design.

Your analysis must cover key performance metrics.

• Latency: This is the time an operation takes to complete. STA helps you identify paths that contribute to high latency.
• Bandwidth: This measures data throughput. Meeting timing is essential for achieving the required bandwidth in your design.

Modern semiconductor processes introduce significant variations. Your STA must account for these effects.

Advanced STA tools use a statistical on-chip variation (SOCV) analysis to model these process differences. For crosstalk, you need a complete SI analysis engine that calculates all relevant timing windows and their overlaps. This ensures your timing measurements are accurate and reliable.

POWER GRID ANALYSIS (IR/EM):

Your power grid is the circulatory system of your chip. Power Grid Analysis verifies its integrity. You must check for two critical issues: IR drop and electromigration (EM).

• IR Drop: As current flows through the metal grid, voltage drops due to resistance. An excessive IR drop can slow down cells, causing timing failures. Your analysis must confirm that every cell receives sufficient voltage.
• Electromigration (EM): High current density can physically move metal atoms in your wires over time. This can cause opens or shorts, leading to chip failure. You must ensure your power grid is robust enough to handle peak currents without degrading.

Running this analysis with realistic switching activity scenarios is crucial for an accurate assessment of your power delivery network.

POWER DOMAIN VERIFICATION:

Modern SoCs use multiple power domains to manage power consumption. You must verify that these domains operate correctly. A mistake here can lead to data corruption or permanent damage. Your verification must confirm the structural and functional correctness of your power management strategy.

You need to perform several critical checks for your power domain design.

• Verify that every signal crossing between power domains has the correct isolation cell or level shifter.
• Ensure that no clock or reset net crosses a shifter.
• Run voltage-aware DRC and LVS checks to validate power rail connectivity.
• Confirm that switching off a power domain does not disrupt connectivity between other active IP blocks.

Your goal is to ensure that a domain correctly restores its state after a power-up sequence. You must also verify that an incorrect sequence does not corrupt retention registers. Achieving high coverage for power-up and power-down events is essential for a robust design.

THERMAL AND HOTSPOT ANALYSIS:

High performance generates heat. Excessive heat can degrade performance and reduce the lifespan of your semiconductor device. You must perform a thermal analysis to identify and mitigate potential hotspots. A hotspot is a small area on the chip that becomes significantly hotter than its surroundings.

Advanced thermal analysis uses a Chip Thermal Model (CTM).

• The CTM divides the chip into a fine grid.
• It details the power output of each grid square as a function of temperature.
• This method accurately predicts the location of thermal hotspots.

Once you identify hotspots, you can use techniques like Dynamic Voltage and Frequency Scaling (DVFS) to manage them. This involves adjusting the chip's voltage and frequency in real-time to control temperature.

SIGNAL INTEGRITY ANALYSIS:

Signal Integrity (SI) analysis ensures that signals travel cleanly from a driver to a receiver. Poor signal integrity can cause data errors, especially on high-speed interfaces. You must analyze critical nets for issues like crosstalk, noise, and reflections.

This analysis is vital for high-speed interfaces such as:

• USB
• HDMI
• DisplayPort
• Ethernet

The primary tool for SI sign-off is the eye diagram. A clean and open "eye" indicates a healthy signal. Your sign-off criteria must include zero eye mask violations. You will also measure key parameters like eye height for noise margin and eye width for timing margin. Analyzing jitter and voltage levels confirms that the receiver can reliably interpret the incoming data.

SYSTEM AND RELIABILITY SIGN-OFF:

This final stage confirms your entire system works together and is reliable for long-term use. You have verified the individual pieces. Now you must validate the complete semiconductor design. This comprehensive check ensures your chip is not only manufacturable and performant but also functionally correct and robust. This is your last major step before the final sign-off.

FULL-CHIP FUNCTIONAL SIMULATION:

You must verify that your complete design works as intended. This involves running application-level scenarios to ensure software and hardware interact correctly. You should run several types of tests to push your design to its limits.

• Basic tests confirm core functionality with simple data packets.
• Stress tests use extreme but valid data to check performance boundaries.
• Random tests feed diverse data to uncover unexpected issues.
• Error tests check how your design handles invalid inputs.

GATE-LEVEL SIMULATIONS (GLS):

Gate-level simulation is essential for catching bugs that RTL simulations miss. GLS uses the post-synthesis netlist, giving you a more accurate view of the final hardware. This is critical for finding timing-related problems.

GLS is your best tool for identifying issues like timing violations, race conditions, and signal glitches caused by gate delays. You should run simulations with and without timing data (SDF) to verify reset sequences and check for setup and hold violations.

DESIGN FOR TEST (DFT) SIGN-OFF:

Your design must be testable after manufacturing. Design for Test (DFT) involves adding structures that help automated testers find defects. For a successful semiconductor product, you must achieve high fault coverage. Industry targets often require over 99% coverage for stuck-at faults and over 90% for at-speed transition faults. Meeting these goals is key to shipping a high-quality semiconductor.

ESD AND LATCH-UP VERIFICATION:

You must protect your chip from electrical hazards. Electrostatic Discharge (ESD) and latch-up checks verify that your design includes adequate protection circuitry. This ensures your device can survive static shocks during handling and will not enter a destructive high-current state during operation.

FINAL GDSII DELIVERY PACKAGE:

This is your final deliverable to the foundry. The GDSII package contains the complete physical layout of your chip. You must ensure the package is correctly formatted and includes all required files and documentation according to HiSilicon’s specifications.

---

This comprehensive design review checklist covers the critical domains for your HiSilicon tape-out. Your design needs physical, performance, and functional verification. You can transform your tape-out process with this checklist. It changes a high-risk gamble into a predictable engineering milestone for your semiconductor design.

A disciplined approach to your semiconductor design is the most reliable path. You can achieve first-time-right semiconductor success. This ensures a quality semiconductor design.

FAQ

What is the biggest mistake in a tape-out process?

The most critical error is using an uncertified PDK or an unapproved IP version. This mistake introduces unknown risks. You build your design on an unstable foundation, which can lead to catastrophic failure and major delays.

How often should you run Design Rule Checks (DRC)?

You should run DRC frequently, not just at the end. Perform checks after key stages:

• Power grid creation
• Cell placement
• Final signal routing

This iterative process helps you find and fix manufacturing violations early, saving significant time.

Why is Gate-Level Simulation (GLS) so important?

GLS verifies your design's timing after synthesis. It finds critical bugs that RTL simulations miss, like race conditions or glitches from gate delays. You must run GLS to confirm your hardware works exactly as intended before manufacturing.

What happens if you miss a small check?

Even a minor oversight can cause a complete tape-out failure. For example, a single off-grid pin can make a block unusable. A missed antenna violation can destroy a transistor. Every check on this list is essential for first-pass silicon success. ✅