function calculateSputterRate() {
// 1. Get DOM elements
var materialSelect = document.getElementById('materialSelect');
var powerInput = document.getElementById('powerInput');
var distanceInput = document.getElementById('distanceInput');
var processTimeInput = document.getElementById('processTime');
var resultsArea = document.getElementById('resultsArea');
// 2. Parse values
var materialBaseRate = parseFloat(materialSelect.value); // This is roughly nm/min per kW at 100mm
var powerKW = parseFloat(powerInput.value);
var distanceMM = parseFloat(distanceInput.value);
var timeMin = parseFloat(processTimeInput.value);
// 3. Validation
if (materialBaseRate === 0) {
alert("Please select a target material.");
return;
}
if (isNaN(powerKW) || powerKW <= 0) {
alert("Please enter a valid power value in kW.");
return;
}
if (isNaN(distanceMM) || distanceMM <= 0) {
alert("Please enter a valid throw distance in mm.");
return;
}
if (isNaN(timeMin) || timeMin <= 0) {
alert("Please enter a valid process time.");
return;
}
// 4. Calculation Logic
// Formula: Rate ~ (BaseRate * Power) * (ReferenceDistance / ActualDistance)^k
// For Magnetrons, geometric fall-off is usually between linear and square depending on track size vs distance.
// We will use a standard approximation factor where Rate is inversely proportional to distance for close range.
// Reference distance is 100mm.
var referenceDist = 100; // mm
// Using a 1.3 exponent for geometric scaling approximation (Magnetron specific)
var distanceFactor = Math.pow((referenceDist / distanceMM), 1.3);
// Calculate Rate in nm/min
var rateNmPerMin = materialBaseRate * powerKW * distanceFactor;
// Convert to Å/sec (1 nm = 10 Å, 1 min = 60 sec)
// Rate (Å/s) = (Rate (nm/min) * 10) / 60
var rateAngPerSec = (rateNmPerMin * 10) / 60;
// Dynamic Deposition Rate Factor (DDR) often quoted in nm*m/min
// This estimates the rate if the substrate moves at 1m/min past the source.
// Simplified estimate for calculator purpose:
var ddr = rateNmPerMin * (0.2); // Approximation factor for standard cathode width
// Total Thickness in Microns (1 µm = 1000 nm)
var totalThicknessNm = rateNmPerMin * timeMin;
var totalThicknessMicrons = totalThicknessNm / 1000;
// 5. Display Results
document.getElementById('rateNmMin').innerHTML = rateNmPerMin.toFixed(2) + " nm/min";
document.getElementById('rateAngSec').innerHTML = rateAngPerSec.toFixed(2) + " Å/s";
document.getElementById('dynamicFactor').innerHTML = ddr.toFixed(2) + " nm·m/min";
document.getElementById('totalThickness').innerHTML = totalThicknessMicrons.toFixed(4) + " µm";
resultsArea.style.display = "block";
}
Understanding Magnetron Sputter Rates
In the field of Thin Film Physical Vapor Deposition (PVD), calculating the sputter rate is crucial for process control and achieving precise film thicknesses. This calculator is designed to estimate deposition rates for rectangular magnetron sputtering sources, similar to those manufactured by Gencoa.
What determines the Sputter Rate?
The deposition rate ($D$) depends primarily on the Sputter Yield of the target material, the Ion Current Density (driven by applied Power), and the geometric setup (Throw Distance).
Key Parameters Explained
Target Material: Different materials have different "Sputter Yields" (the number of atoms ejected per incident ion). For example, Silver (Ag) and Gold (Au) sputter much faster than Titanium (Ti) or Carbon due to their atomic bond strength and mass.
Discharge Power (kW): In DC and Pulsed-DC sputtering, the rate is generally linear with power. Doubling the power (kW) typically doubles the number of ions hitting the target, thus doubling the material ejected.
Throw Distance: As the substrate moves further from the cathode target, the material flux decreases. For planar magnetrons, this drop-off follows a geometric decay, often approximated between inverse-linear and inverse-square laws depending on the source size.
Dynamic vs. Static Deposition
Gencoa and other magnetron manufacturers often distinguish between Static Rate (accumulation on a stationary substrate) and Dynamic Deposition Rate (DDR). DDR is critical for roll-to-roll web coating or inline glass coating, where the substrate moves past the cathode.
This calculator provides the Static Rate as a baseline. To optimize your specific process, consider the impact of reactive gases (Oxygen/Nitrogen) which can cause "target poisoning," significantly reducing rates compared to the metallic mode calculations provided above.
Optimizing Uniformity and Yield
High-quality magnetrons, such as those with Gencoa's variable magnetic bars, allow operators to tune the magnetic field to improve target utilization and thickness uniformity. While this calculator gives a theoretical estimation, real-world rates are influenced by gas pressure, magnetic field strength, and the specific "racetrack" erosion profile of your target.