Apparatus for baking resist on semiconductor wafers
US4518848A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 15, 1981 |
| Grant date | May 21, 1985 |
| Priority date | — |
| Expiry date | May 15, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/40
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In the resist baking apparatus disclosed herein, heating of the wafer is effected by direct contact with a thin disc-like heating plate whose heat capacity is not greatly disparate from that of the wafer. The heating plate is initially brought to a temperature higher than that which is to be applied to the resist but the corresponding cooling of the plate as the wafer is initially heated prevents damaging temperatures from reaching the resist. The heater plate is perforate and air pressure is utilized to support a wafer over the heater plate before heating is to begin and also to later lift the wafer and thereby sharply define the end of heating. During baking, a vacuum is applied through these same perforations to clamp the wafer tightly against the heating plate for tight thermal coupling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.