Material Properties Database

1. PCB Substrates (Dielectrics)

| Material | Dk ($\epsilon_r$) | Df ($\tan\delta$) | Description | |----------|-------------------|-------------------|-------------| | FR-4 | 4.3 - 4.8 | 0.020 | Cheap, lossy, variances. Good < 1GHz | | Rogers 4350B | 3.66 | 0.0037 | Standard RF hybrid board | | Rogers 4003C | 3.55 | 0.0027 | Lower loss, rigid | | Rogers 3003 | 3.00 | 0.0010 | PTFE based, very low loss | | Alumina ($Al_2O_3$) | 9.8 | 0.0002 | Ceramic, high Dk, hard | | Teflon (PTFE) | 2.1 | 0.0002 | Lowest loss, soft |

2. Conductor Properties

| Metal | Conductivity ($\sigma$) [S/m] | Skin Depth @ 1GHz [$\mu m$] | |-------|-------------------------------|-----------------------------| | Silver | $6.30 \times 10^7$ | 2.01 | | Copper | $5.96 \times 10^7$ | 2.06 | | Gold | $4.10 \times 10^7$ | 2.48 | | Aluminum | $3.50 \times 10^7$ | 2.69 | | Nickel | $1.43 \times 10^7$ | ~0.5 (Ferromagnetic!) |

Note: Nickel plating (ENIG) often destroys RF performance due to magnetic properties.