Pressure transmitter for a semiconductor processing environment

Abstract

Embodiments related to measuring process pressure in low-pressure semiconductor processing environments are provided. In one example, a semiconductor processing module for processing a substrate with a process gas in a vacuum chamber is provided. The example module includes a reactor positioned within the vacuum chamber for processing the substrate with the process gas and a pressure-sensitive structure operative to transmit a pressure transmission fluid pressure to a location exterior to the vacuum chamber. In this example, the pressure transmission fluid pressure varies in response to the process gas pressure within the vacuum chamber.

1 . A semiconductor processing module for processing a substrate with a process gas in a vacuum chamber, the semiconductor processing module comprising:
 a reactor positioned within the vacuum chamber for processing the substrate with the process gas; and   a pressure-sensitive structure operative to transmit a pressure transmission fluid pressure to a location exterior to the vacuum chamber, such pressure transmission fluid pressure varying in response to a pressure of the process gas.   
     
     
         2 . The semiconductor processing module of  claim 1 , the reactor comprising a top plate and a bottom plate coupled to the top plate. 
     
     
         3 . The semiconductor processing module of  claim 2 , further comprising:
 a susceptor moveably sealable to the bottom plate so that the substrate is supported in a low-pressure substrate processing environment when the susceptor is sealed to the bottom plate;   a process feed plenum coupled to the reactor for supplying the process gas to the low-pressure substrate processing environment upstream of a substrate positioned in the low-pressure substrate processing environment; and   a process exhaust collector coupled to the reactor for collecting the process gas downstream of the substrate;   wherein the process feed plenum and the process exhaust collector are arranged to direct the process gas across a process surface of the substrate.   
     
     
         4 . The semiconductor processing module of  claim 3 , the pressure-sensitive structure being positioned downstream of the process surface of the substrate. 
     
     
         5 . The semiconductor processing module of  claim 3 , wherein the pressure-sensitive structure has a process side being exposed to the low-pressure substrate processing environment, the process side being mounted flush with a surface of the bottom plate. 
     
     
         6 . The semiconductor processing module of  claim 3 , the pressure-sensitive structure being included in the process exhaust collector. 
     
     
         7 . The semiconductor processing module of  claim 3 , the pressure-sensitive structure being included in the process feed plenum. 
     
     
         8 . The semiconductor processing module of  claim 1 , wherein the pressure-sensitive structure includes a displaceable diaphragm having a process side exposable to the process gas and a transmission side opposite the process side. 
     
     
         9 . The semiconductor processing module of  claim 8 , further comprising:
 a pressure sensor adapted to detect the pressure transmission fluid pressure at the location exterior to the vacuum chamber; and   a pressure transmission fluid line for fluidically coupling the pressure sensor to the displaceable diaphragm with a pressure transmission fluid that is in contact with the transmission side of the displaceable diaphragm so as to transmit process pressure information, responsive to movement of the displaceable diaphragm, from the process gas to the pressure sensor.   
     
     
         10 . The semiconductor processing module of  claim 9 , the pressure sensor including a pressure sensor diaphragm for transmitting process pressure information to the pressure sensor via movement of the pressure sensor diaphragm; and
 the pressure transmission fluid line including a purge valve for purging the pressure transmission fluid line.   
     
     
         11 . The semiconductor processing module of  claim 9 , the pressure-sensitive structure comprising a reservoir formed below the transmission side, the reservoir fluidically coupled with the pressure transmission fluid line, wherein the reservoir, the pressure transmission fluid line, and the displaceable diaphragm are sealably coupled. 
     
     
         12 . The semiconductor processing module of  claim 1 , further comprising:
 a second pressure-sensitive structure operative to transmit a second pressure transmission fluid pressure to a second location exterior to the vacuum chamber.   
     
     
         13 . A reactor defining a low-pressure substrate processing environment for processing a substrate, the reactor comprising:
 a top plate;   a bottom plate coupled to the top plate;   a susceptor moveably sealable to the bottom plate so that the substrate is supported in the low-pressure substrate processing environment when the susceptor is sealed to the bottom plate; and   a displaceable diaphragm included in the bottom plate, the displaceable diaphragm adapted to transmit process pressure information for the low-pressure substrate processing environment responsive to movement of the displaceable diaphragm.   
     
     
         14 . The reactor of  claim 13 , further comprising an inlet for receiving process gas from a process feed plenum upstream of a process surface of the substrate and an outlet for expelling the process gas to a process exhaust collector downstream of the process surface of the substrate, the inlet and the outlet being arranged to direct the process gas across the process surface of the substrate and wherein the displaceable diaphragm is positioned downstream of the process surface of the substrate. 
     
     
         15 . The reactor of  claim 13 , the displaceable diaphragm including a process side that is flush with a top surface of the bottom plate, the top surface being exposed to the low-pressure substrate processing environment. 
     
     
         16 . The reactor of  claim 13 , the displaceable diaphragm further including a reservoir formed below a transmission side of the displaceable diaphragm. 
     
     
         17 . The reactor of  claim 16 , wherein the displaceable diaphragm and the reservoir are sealably coupled. 
     
     
         18 . The reactor of  claim 16 , further comprising a pressure transmission fluid line for fluidically coupling the reservoir to a pressure sensor with a pressure transmission fluid that is in contact with the transmission side of the displaceable diaphragm. 
     
     
         19 . At a process controller of a semiconductor processing module, a method for processing a substrate in a vacuum chamber of the semiconductor processing module, the method comprising:
 supporting a substrate with a susceptor within the vacuum chamber;   supplying a process gas to the vacuum chamber; and   transmitting to a location exterior to the vacuum chamber a pressure transmission fluid pressure with a pressure-sensitive structure, the pressure transmission fluid pressure varying in response to a process gas pressure within the vacuum chamber.   
     
     
         20 . The method of  claim 19 , wherein supplying the process gas comprises supplying the process gas upstream of a process surface of the substrate so that the process gas flows across the process surface of the substrate before flowing across the pressure-sensitive structure.