15,404 technical terms and definitions
rdl chip packaging, rdl explained, what does rdl mean semiconductor, redistribution layer packaging
A redistribution layer, or RDL, is a thin layer of extra wiring built on top of a finished chip that reroutes its native connection points to new, more convenient locations…
rf front end explained, rf front end meaning, phone rf module, what does rf front end do
An RF front-end module is the collection of specialized components — including power amplifiers, filters, and switches — that sits between a device's modem chip and its antenna…
semiconductor explained, semiconductor definition, semiconductor vs conductor vs insulator, what is silicon used for
A semiconductor is a material — most commonly silicon — whose ability to conduct electricity sits between that of a true conductor (like copper) and a true insulator (like glass)…
chip ip core explained, ip licensing semiconductor meaning, what is ip core in chip design, processor ip licensing
A semiconductor IP core is a pre-designed, reusable block of chip circuitry — such as a processor core, a memory controller, or a communications interface — that a chip designer…
gate spacer fabrication, self aligned source drain, anisotropic etch spacer formation, conformal deposition spacer, transistor spacer width
A spacer is a thin sidewall of insulating material formed against the edges of a transistor's gate, and it exists to precisely control where the source and drain regions begin…
soc explained, system on chip meaning, what does soc mean in phones, soc vs cpu
A system on chip, or SoC, is a single chip that combines multiple major components of a computing system — typically a processor, memory controller, graphics, and other…
systolic array explained, systolic array tpu, systolic array meaning ai, what does systolic array mean
A systolic array is a grid-like arrangement of simple processing units that pass data to their immediate neighbors in a steady, rhythmic pattern, allowing an AI accelerator…
chip tape out explained, tape out meaning semiconductor, what does tape out mean, chip design tape out
Tape-out is the moment a chip's design is finalized and sent off to a foundry for manufacturing — the point of no return in chip development, after which making changes means…
tsv explained, through silicon via meaning, tsv chip packaging, what does tsv stand for
A through-silicon via, or TSV, is a microscopic vertical electrical connection drilled directly through a piece of silicon, allowing signals to pass straight up and down between…
tensor processing unit explained, tpu vs gpu, tpu meaning ai chip, what does tpu stand for
A TPU, or Tensor Processing Unit, is a type of AI accelerator chip designed specifically to speed up the tensor math — large-scale multi-dimensional array operations — that…
transistor explained, how does a transistor work, transistor switch, cmos transistor basics
A transistor is a tiny electronic switch that can flip between "on" and "off" billions of times per second, and it is the single building block that every modern chip is made…
turbo pump semiconductor fab, high vacuum pump explained, staged vacuum pump down, plasma chamber vacuum requirements, molecular flow vacuum pump
A turbomolecular pump is the workhorse vacuum pump that gets a process chamber down to the extremely low pressures nearly every fab process covered in this series actually…
vector processing explained, vector processor vs scalar, simd vector processor meaning, what does a vector processor do
A vector processor is a type of processor built to apply the same single operation to many data elements at once, rather than processing one value at a time — a design well suited…
silicon wafer explained, semiconductor wafer meaning, wafer fabrication, what is a die vs wafer
A wafer is a thin, round slice of ultra-pure silicon — typically about 300 millimeters across on modern production lines — that serves as the base material on which an entire…
subtractive interconnect process, aluminum vs copper interconnect, chlorine plasma etch aluminum, metal wiring fabrication, aluminum etch profile
Aluminum metal etch is the process step that patterns aluminum wiring into the precise interconnect shapes a chip design calls for, and it represents an older interconnect…
ai accelerator chip explained, ai accelerator vs gpu, ai accelerator meaning, types of ai accelerators
An AI accelerator is any chip built specifically to speed up the math behind artificial intelligence — mostly large-scale matrix multiplication — rather than to handle…
npu explained, neural processing unit, npu vs gpu vs cpu, on-device ai chip
An NPU, or Neural Processing Unit, is a chip or chip block built specifically to run the repetitive math behind neural networks — mostly large batches of matrix multiplication…
osat semiconductor meaning, outsourced assembly and test explained, osat vs foundry, chip packaging and testing company
An OSAT — short for Outsourced Semiconductor Assembly and Test — is a company that specializes in packaging finished silicon dies and testing completed chips, handling…
transformer attention explained, query key value attention, kv cache explained, multi query attention, grouped query attention, self attention transformer
The attention mechanism is the calculation that lets a transformer decide, for every token it's producing, which earlier tokens actually matter right now — and it's exactly what…
beamforming explained, beamforming 5g meaning, how does beamforming work, beamforming antenna array
Beamforming is a wireless antenna technique that combines signals from multiple antenna elements so they reinforce each other in a specific direction, effectively focusing…
chip packaging explained, semiconductor packaging meaning, advanced packaging chiplets, what is a chip package
Chip packaging is the process of taking a finished, tested silicon die and encasing it in a protective housing with external connectors — the familiar black rectangle with metal…
Clock domain crossing is the transfer of a signal from a circuit block running on one clock to a circuit block running on a different, asynchronous clock, a situation that…
clock speed explained, cpu ghz meaning, what is clock frequency, clock speed vs performance
Clock speed, measured in gigahertz (GHz), is how many times per second a chip's internal clock ticks, and each tick synchronizes one step of work across the chip's circuits — but…
chemical mechanical polishing explained, planarization semiconductor, cmp dishing erosion, copper damascene cmp, preston equation polishing
Chemical-Mechanical Polishing (CMP) is what flattens the wafer back out after deposition and etch leave it bumpy. Every layer built through the CVD-lithography-etch loop leaves…
compute in memory explained, in memory computing ai, compute in memory chip meaning, what does compute in memory mean
Compute-in-memory is a chip architecture approach that performs certain calculations directly inside memory itself, rather than following the traditional design of moving data out…
dynamic batching llm serving, in-flight batching explained, llm throughput scheduling, static vs continuous batching, ai serving scheduler
Continuous batching is the serving-system technique that decides which requests actually get processed together on any given decode step, and it's the layer where every…
damascene process explained, dual damascene semiconductor, copper electroplating BEOL, barrier metal liner copper, low-k dielectric interconnect
Copper interconnect is the wiring that connects millions or billions of individual transistors into an actual working circuit. Once the transistors themselves are built through…
cpu cache explained, l1 l2 l3 cache, how does cache memory work, cache hit miss
CPU cache is a small amount of extremely fast memory built directly into the processor to hide an enormous speed gap: a modern CPU can perform an operation in a fraction of…
critical dimension explained, cd semiconductor meaning, critical dimension lithography, what does cd mean in chip manufacturing
Critical dimension, often abbreviated CD, refers to the smallest, most precisely controlled feature size on a chip — typically the width of the narrowest transistor gate or wire…
cryogenic plasma etch explained, high aspect ratio sidewall control, low temperature etch semiconductor, tsv etch profile, gaa release etch sidewall bowing
Cryo etch is plasma etching performed with the wafer cooled to extremely low temperatures, and it exists to solve an etch-profile problem that ordinary room-temperature…
chemical vapor deposition explained, CVD vs ALD semiconductor, PECVD LPCVD thermal CVD, step coverage conformality, thin film deposition chip fabrication
Chemical Vapor Deposition (CVD) is how a fab builds material up on the wafer instead of carving it away. Where plasma etch removes everything outside the mask, CVD does…
dof lithography explained, depth of focus meaning chip, lithography focus tolerance, dof semiconductor
Depth of focus, or DOF, is the vertical range above and below a lithography system's ideal focal plane within which a pattern can still be exposed sharply enough to be usable…
all reduce explained, ring allreduce vs tree allreduce, gradient synchronization gpu cluster, collective communication ai training, training cluster interconnect bandwidth
Distributed training is how a single model gets trained across thousands of chips at once, and the mechanism that makes it work — collective communication, most commonly…
deep ultraviolet lithography explained, duv vs euv, duv lithography meaning, 193nm lithography
DUV, or deep ultraviolet lithography, is the workhorse lithography technology that patterned chips for decades before EUV arrived, using a longer wavelength of ultraviolet light…
edge ai explained, edge ai vs cloud ai, on-device ai meaning, what does edge ai mean
Edge AI means running artificial intelligence directly on the device where data is generated — a phone, a camera, a car, a factory sensor — instead of sending that data to…
euv lithography explained, extreme ultraviolet lithography meaning, how does euv work, euv chip manufacturing
EUV lithography is a chipmaking technique that uses extreme ultraviolet light — with a wavelength roughly fourteen times shorter than the light used in older lithography methods…
fabless company meaning, fabless vs idm, fabless semiconductor model, what does fabless mean
A fabless company designs chips but doesn't own or operate the factories that manufacture them, instead paying a foundry to fabricate its designs — a business model that lets…
federated learning explained, federated ai training meaning, federated learning privacy, what does federated learning do
Federated learning is a way of training AI models across many separate devices or locations without ever centralizing the underlying data — each device trains on its own local…
what is a finfet, gate all around transistor explained, nanosheet transistor architecture, 3nm transistor structure, gate all around vs finfet
FinFET and GAA (Gate-All-Around) are the two transistor shapes the entire fab process you've just walked through was actually built to produce. Every step covered so far — litho…
flip chip explained, flip chip vs wire bonding, flip chip bonding meaning, what does flip chip mean
Flip chip packaging is a method of connecting a silicon die to its package by flipping the die upside down and attaching it directly via an array of tiny solder bumps across its…
high k dielectric explained, gate leakage quantum tunneling, silicon dioxide gate insulator, transistor gate dielectric, gate oxide thickness scaling
Gate oxide is the thin insulating layer sitting directly between a transistor's gate and its channel, and its whole job is to let the gate control the channel electrically without…
multi query attention explained, gqa vs mqa, kv cache size reduction, attention heads sharing keys values, llm serving memory optimization
Multi-query and grouped-query attention are two ways of shrinking the KV cache itself, by making multiple attention heads share the same keys and values instead of each head…
hbm explained, hbm meaning ai chips, high bandwidth memory vs regular memory, what does hbm stand for
High bandwidth memory, or HBM, is a type of memory built by stacking multiple memory dies vertically and connecting them with extremely short, wide internal connections, achieving…
immersion lithography explained, water immersion lithography meaning, duv immersion, immersion lithography vs euv
Immersion lithography is a technique that places a thin layer of purified water between the lens and the wafer during DUV lithography, using water's optical properties to bend…
ion implantation explained, semiconductor doping process, boron phosphorus arsenic dopant, spike anneal activation, source drain junction implant
Ion implantation is how a fab actually changes silicon's electrical personality, not just its shape. Etch and CVD sculpt and build up physical structure, but neither one turns…
ler lithography explained, line edge roughness meaning, chip manufacturing edge roughness, what does ler mean
Line edge roughness, or LER, refers to the small, irregular waviness along the edges of a patterned feature on a chip — instead of a perfectly smooth, straight line, real…
prefill vs decode explained, kv cache transformer, roofline model ai accelerator, llm serving throughput latency, memory bandwidth bound inference
LLM inference is running an already-trained model forward to answer a live request, and it behaves nothing like training on the hardware underneath it. Training adjusts a model's…
semiconductor metrology explained, wafer inspection defect detection, CD-SEM overlay scatterometry, statistical process control fab, OCD critical dimension measurement
Metrology and inspection are how a fab knows whether the last 60 process steps actually worked, without waiting until the finished chip fails to find out. After nearly every…
mmwave explained, millimeter wave 5g meaning, mmwave vs sub-6, what does mmwave mean
Millimeter wave, often called mmWave, refers to a very high-frequency band of radio spectrum used by some 5G networks, offering dramatically more available bandwidth and faster…
mimo wireless explained, mimo meaning 5g, multiple input multiple output, what does mimo stand for
MIMO, short for multiple-input multiple-output, is a wireless technology that uses multiple antennas at both the transmitter and receiver to send and receive several data streams…