1. A high-side switch circuit that switches and outputs a power supply voltage, comprising:
a first output MOS transistor that is connected, at a first end thereof, to a power supply terminal to which the power supply voltage is applied;
a second output MOS transistor that is connected to a second end of the first output MOS transistor at a first end thereof and to a voltage output terminal at a second end thereof;
a current detecting circuit that detects a current flowing through the first output MOS transistor and outputs a detection signal based on the result of the detection;
a first gate driver that applies a first control voltage to a gate of the first output MOS transistor so as to make the first output MOS transistor operate in a linear region; and
a second gate driver that applies a second control voltage to a gate of the second output MOS transistor so as to make the second output MOS transistor operate in a linear region,
wherein the first gate driver applies the first control voltage to the gate of the first output MOS transistor in response to the detection signal so as to limit the current flowing through the first output MOS transistor when the current flowing through the first output MOS transistor exceeds a preset threshold;
wherein the current detecting circuit comprises:
a detecting resistor that is connected to the power supply terminal at a first end thereof;
a detecting MOS transistor that is connected to a second end of the detecting resistor at a first end thereof, to the second end of the first output MOS transistor at a second end thereof and to the gate of the first output MOS transistor at a gate thereof;
a reference voltage generating circuit that generates a reference voltage that is lower than a voltage at the power supply terminal by a predetermined value; and
a comparator that compares the reference voltage and a detected voltage between the second end of the detecting resistor and the first end of the detecting MOS transistor and outputs a detection signal determined by the result of the comparison, and
wherein the comparator comprises:
a first transistor to a first end of which the reference voltage is applied that forms a first current mirror circuit;
a second transistor that is connected to the second end of the detecting resistor at a first end thereof and to a control terminal of the first transistor at a control terminal thereof and forms the first current mirror circuit;
a third transistor that is connected to a second end of the first transistor at a first end thereof and to a ground at a second end thereof and forms a second current mirror circuit;
a fourth transistor that is connected to a second end of the second transistor at a first end thereof and to a control terminal of the third transistor at a control terminal thereof and forms the second current mirror circuit; and
a fifth transistor that is connected, at a first end thereof, to a terminal at which the detection signal of the comparator is output, to the ground at a second end thereof and to the first end of the third transistor at a control terminal thereof.
2. The high-side switch circuit according to claim 1, further comprising:
a first clamping circuit that is connected between the first end and the gate of the first output MOS transistor and clamps a voltage between the first end and the gate of the first output MOS transistor so that the voltage between the first end and the gate of the first output MOS transistor does not exceed a gate withstand voltage of the first output MOS transistor; and
a second clamping circuit that is connected between the first end and the gate of the second output MOS transistor and clamps a voltage between the first end and the gate of the second output MOS transistor so that the voltage between the first end and the gate of the second output MOS transistor does not exceed a gate withstand voltage of the second output MOS transistor.
3. The high-side switch circuit according to claim 2, wherein the first clamping circuit comprises a first Zener diode that is connected to the first end of the first output MOS transistor at a cathode thereof and to the gate of the first output MOS transistor at an anode thereof, and
the second clamping circuit comprises a second Zener diode that is connected to the first end of the second output MOS transistor at a cathode thereof and to the gate of the second output MOS transistor at an anode thereof.
4. The high-side switch circuit according to claim 1, wherein the first transistor has a size that is equal to a size of the second transistor, and the third transistor has a size that is equal to a size of the fourth transistor.
5. The high-side switch circuit according to claim 1, wherein the comparator further comprises:
a first resistor that is connected between the second end of the first transistor and the first end of the third transistor;
a second resistor that is connected between the second end of the second transistor and the first end of the fourth transistor; and
a third resistor that is connected between the second end of the first transistor and the control terminal of the fifth transistor.
6. The high-side switch circuit according to claim 1, wherein the second transistor and the fourth transistor are diode-connected.
7. The high-side switch circuit according to claim 1, wherein the first to fifth transistors are bipolar transistors.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of processing a substrate, comprising:
positioning the substrate on a support in a processing chamber;
providing a first organosilicon precursor to the chamber at a first flow rate;
providing a second organosilicon precursor comprising to the chamber at a second flow rate;
providing a hydrocarbon mixture to the chamber at a third flow rate;
providing an oxidizing agent to the chamber at a fourth flow rate;
ramping the second flow rate of the second organosilicon precursor to a higher flow rate;
ramping the flow rate of the oxidizing agent to a higher flow rate; and
diverting the hydrocarbon mixture to bypass the chamber for at least part of the time the substrate is being processed.
2. The method of claim 1, wherein the first organosilicon precursor has a lower ratio of carbon atoms to silicon atoms than the second organosilicon precursor.
3. The method of claim 1 wherein the hydrocarbon mixture comprises one or more compounds having cyclic groups.
4. The method of claim 1, wherein ramping the second flow rate of the second organosilicon precursor comprises a ramp rate faster than the ramp rate used to ramp the oxidizing agent.
5. The method of claim 1, further comprising ramping the first flow rate of the first organosilicon precursor to a higher flow rate.
6. The method of claim 1 further comprising ramping the third flow rate of the hydrocarbon mixture to a higher flow rate.
7. The method of claim 1, wherein the first organosilicon precursor, the second organosilicon precursor, the hydrocarbon mixture, and the oxidizing agent form a reaction mixture in the process chamber, and the ratio of carbon atoms to silicon atoms in the reaction mixture increases from about 3:1 to about 20:1 during processing of the substrate.
8. A method of processing a substrate, comprising:
providing a plurality of gas mixtures comprising silicon, carbon, oxygen, and hydrogen to a processing chamber, wherein at least two of the gas mixtures are silicon sources;
providing plasma processing conditions by applying RF power to the processing chamber;
reacting at least a portion of the gas mixtures to deposit a film on the substrate; and
adjusting the carbon content in portions of the deposited film by adjusting a ratio of carbon to silicon atoms in the processing chamber during application of RF power.
9. The method of claim 8, wherein adjusting the ratio of carbon to silicon atoms in the processing chamber comprises diverting one or more of the gas mixtures to bypass the chamber.
10. The method of claim 8, wherein the plurality of gas mixtures comprises a first gas mixture comprising one or more organosilicon compounds having \u2014Si\u2014Cx\u2014Si\u2014 bonds.
11. The method of claim 10, wherein the plurality of gas mixtures further comprises a second gas mixture comprising one or more hydrocarbon compounds having thermally labile groups.
12. The method of claim 8, further comprising generating pores in the deposited film by post-treating the substrate.
13. The method of claim 11, wherein adjusting the ratio of carbon to silicon atoms in the processing chamber comprises diverting the one or more hydrocarbon compounds to bypass the processing chamber.
14. The method of claim 8, wherein adjusting the carbon content of the deposited film comprises depositing an oxide-like portion of the film with low carbon content, increasing the carbon content smoothly in a transition portion of the film, and depositing an oxycarbide-like portion of the film with maximum carbon content.
15. A method of depositing a low-k dielectric film on a substrate disposed in a processing chamber, comprising:
providing a first gas mixture comprising one or more compounds having \u2014Si\u2014Cx\u2014Si\u2014 or \u2014Si\u2014Cx\u2014O\u2014Si\u2014 bonds, and having a ratio of carbon to silicon atoms less than about 6:1, to the processing chamber;
with the first gas mixture, providing a second gas mixture comprising one or more compounds having \u2014Si\u2014Cx\u2014Si\u2014 or \u2014Si\u2014O\u2014Cx\u2014O\u2014Si\u2014 bonds, and having a ratio of carbon to silicon atoms greater than about 8:1, to the processing chamber;
providing a third gas mixture comprising one or more hydrocarbon compounds to the processing chamber, at least one of the one or more hydrocarbon compounds having thermally labile groups, to the processing chamber;
providing a fourth gas mixture comprising oxygen sources to the processing chamber;
applying RF power and reacting at least a portion of the gas mixtures to deposit a film on the substrate;
while applying RF power, adjusting the amounts of one or more of the gas mixtures containing carbon to change the deposition rate of carbon in the film; and
post-treating the deposited film to lower the dielectric constant of the film.
16. The method of claim 15, wherein the one or more compounds having \u2014Si\u2014Cx\u2014Si\u2014 or \u2014Si\u2014O\u2014Cx\u2014O\u2014Si\u2014 bonds are each selected from the group consisting of bis(triethoxysilyl)methane (C13H32O6Si2), tetramethyl-1,3-disilacyclobutane (C6H16Si2), tetramethyl-2,5-disila-1-oxacyclopentane, tetramethyldisilafuran (C6H16OSi2), and bis(trimethylsiloxy)ethane (C8H22O2Si2).
17. The method of claim 15, wherein adjusting the gas mixtures containing carbon comprises ramping the flow rate of the second gas mixture upward.
18. The method of claim 17, wherein adjusting the gas mixtures containing carbon further comprises ramping the flow rate of the third gas mixture upward.
19. The method of claim 15, wherein adjusting the gas mixtures begins when the reaction begins.
20. The method of claim 15, wherein post-treating the deposited film generates pores in the portions of the film having higher carbon content.