| Gold Finish |
May be Electrolytic Electroless, or Immersion |
| ENIG (Electroless Nickel Immersion Gold) |
2-5 micro inches. Purpose: To prevent oxidation, extend shelf life, provide a wire bonding surface, and used to provide an electrically conductive surface on PCBs. Used for solderability when the flatness of the pad is critical. |
| Hard Gold |
Purpose: Used for Gold Fingers (minimum 30 micro inches), soldering (maximum 17 micro inches), to prevent oxidation and extend shelf life. |
| Soft Gold |
Purpose: Used for wire bonding (Ultrasonic minimum 2 micro inches/Thermasonic minimum 12 micro inches) and to prevent oxidation and extend shelf life. |
| Immersion Silver |
Use for solderability purposes (2-5 micro inches). Used for solderability when the flatness of the pad is critical. |
| Lead Free Solder |
Use for solderability purposes (2-5 micro inches). Used for solderability when the flatness of the pad is not critical. |
| OSP (Organic Solderability Preservatives) |
Used for solderability when the flatness of the pad is critical. |
| White Tin (Immersion Tin) |
Used for solderability when the flatness of the pad is critical. |
